# 16 Ohm vs 8 Ohm Speaker. Which? and Why?



## paul-e-mann

If my amp has the ability to plug into it a 16 Ohm or 8 Ohm speaker, why would I choose one over the other? Advantages? Disadvantages? 

I've heard some people say it doesnt matter, and others say one has better response over the other. I just dont know. Lets hear what everybody has to say at Marshall Forum


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## chuckharmonjr

The only thing that matters is that you match the impedances. 8 ohm speaker into 8 ohm amp plug, etc. There is no difference, given the exact same speaker, between a 16 ohm version and an 8 ohm version. Just match up the impedances to keep your OT from melting down.


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## Ken

The only advantage is if you're making a stack and only have another 8 or 16 ohm cabinet. Nothing else matters as far as I'm concerned. 

Ken


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## MajorNut1967

There's no advantage to running either 16 or eight. As long as the impedance of the amp and the speaker match then you'll be fine. The 16 ohm impedance is a British thing. You can look it up, I'm not going to explain here.

Some people believe that if you use a 16 tap that you are engaging the full winding of the secondary, therefore getting the full spectrum of the audio. I don't know if this is true or if someone actually said it was true I don't know that I would believe them.


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## rjohns1

I just read Gerald Weber's third book "Tube Guitar Amp Essentials". Very informative book. He advocates what you are describing about the whole winding theory. While I can see that maybe in a laboratory environment, with super accurate measuring equipment, you might be able to tell the difference, no dude in a full band scenario is really gonna tell if there is any noticeable difference. I doubt recording wise you could tell either. I think the only difference you would see anyway is slight increase or decrease in total output, and that would so minor, the human ear probably could not hear it.


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## thetragichero

yeah i only would ever care if one could make me louder


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## MartyStrat54

There you go. Now that's a hardcore forum member right there.


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## manktelow

I like this argument. There are many people on the forum that have been playing electric guitar for decades. Plus all the players that they have met. If there was an Ohm setting that sounded the best, it would be common knowledge by now.


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## Adwex

Once, about 15 years ago, I experimented with switching back and forth from 16 to 4, and I didn't notice any difference.
I stuck with 16 ever since.


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## Adwex

pedecamp said:


> If my amp has the ability to plug into it a 16 Ohm or 8 Ohm speaker, why would I choose one over the other? Advantages? Disadvantages?
> 
> ....



The only reason to use one over the other would be the quality/sound of the speaker, not the impedance.


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## chuckharmonjr

Two identical cabs, both with say greenies...or g12m-70's...or whatever...but identical except one cab is 8 ohm the other is 16...there is zero difference between the two cabs so long as you match the amp's impedance to the cab. As far as OT winding, you are just changing the amount of winding engaged so to speak to limit the power output exposure of the power tubes to be the same at a given impedance.


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## Moose Lewis

In the early '70s, I experimented with building my own cabs, speaker configurations and models of speakers available at the time (which is why I still stick with Celestions for guitar amps, even though some speaker manufacturers who made pure crap back then apparently have nice stuff nowadays). Unfortunately I no longer have the tools, cash or motivation for such experiments - so I lurk around forums and ask stupid questions in hopes I will make intelligent purchases to get on with music production; eking out a living from my little studio without wasting more money (and _thanks to all_ for sharing such knowledge).

I _have_ to bow before the superior technical knowledge of the more scholastic members here who have _obviously_ done their research... but I will also share the opinion of an old rocker who is possibly crazy as a sh*thouse rat by now.

Short and sweet - 4ohm configurations seemed to provide more clean volume (which is how I wire my PA speakers), 16ohm provided more breakup and smoother distortion while allowing me to drive the amp harder with less resulting volume. 8ohms felt closer to the 16ohm cabs than the 4ohm.

While I was not alone in this opinion back in the day, from what I've read here it is probably pure BS - but I still hear the difference, and it makes me happy - so I thought I would share a different viewpoint.


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## el zilcho

Speakers wired in series can intermodulate each other. I think it's more likely to make a difference with a high powered subwoofer system than a guitar cab.

As for the speakers themselves, there are some guitar speakers with different parameters for the 8ohm vs. 16ohm model. I think this is because the 8ohms are mostly getting installed in open back combos.


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## CraigP

Old post still helpful. Was just having a discussion on this topic earlier this afternoon.


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## Micky

The ONLY time I would choose a specific impedance would be when building a cab.
And then, only in order to provide maximum versatility and to match my amps.

For example, a single 1X12 or a 4X12, I would choose 16-ohm speakers.
For a 2X12, I would choose 8-ohm speakers and wire them in series.
(if I had to, I would use 16-ohm speakers and wire them in parallel...)


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## FabioPol

Moose Lewis said:


> In the early '70s, I experimented with building my own cabs, speaker configurations and models of speakers available at the time (which is why I still stick with Celestions for guitar amps, even though some speaker manufacturers who made pure crap back then apparently have nice stuff nowadays). Unfortunately I no longer have the tools, cash or motivation for such experiments - so I lurk around forums and ask stupid questions in hopes I will make intelligent purchases to get on with music production; eking out a living from my little studio without wasting more money (and _thanks to all_ for sharing such knowledge).
> 
> I _have_ to bow before the superior technical knowledge of the more scholastic members here who have _obviously_ done their research... but I will also share the opinion of an old rocker who is possibly crazy as a sh*thouse rat by now.
> 
> Short and sweet - 4ohm configurations seemed to provide more clean volume (which is how I wire my PA speakers), 16ohm provided more breakup and smoother distortion while allowing me to drive the amp harder with less resulting volume. 8ohms felt closer to the 16ohm cabs than the 4ohm.
> 
> While I was not alone in this opinion back in the day, from what I've read here it is probably pure BS - but I still hear the difference, and it makes me happy - so I thought I would share a different viewpoint.


I absolutely hear a difference when I change the impedance setting, I do much prefer when my amps are 8 ohm and the cabs 16 ohm, I hear more headroom, 16/16 too distorted, 4/16 bleah....some guys I know they like the sound of the 8 ohm mesaboogie vintage 30....my bandmate bought a quartet and loaded in his Marshall cab because once he tried a mesa cab....it is quite chaotic in the case of vintage 30 because not all are the same ( as far as I know there are 3 production line )....I have 2 1960 vintage cabs each loaded with vintage 30 ( Marshall labelled) with different codes.....and they sound slightly different ( one quartet darker then the other)....so someone could like one speaker more then the other thinking it is because the ohm's but could be because the difference in voicing....then I've never compared 16 to 8 ohm speaker so I cannot say more


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## paul-e-mann

6 years later I still have no clue...


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## dreyn77

I'm NOT supprised about that. 
16 years and now I know all about the JCM2000 amp. I've heard all the 'so called' experts for all that time and so, now I know I've wasted 16 years of my life listening to total dummies. 

its a loudness effect if you want to think of it that way. but even now, those 'louder' ohm'ed speakers have been reworked and are now built to be louder than they use to be. Everything is now exployted to the max, cause that's how they make NEW sounds. 
so if you want to findout what happens with ohm's then you'll need mixed vintage speakers. 

so now, in 2016, nothing makes any sense in this technical talk, cause it's all been pushed to the max, and backed off just a small amount. (sound familiar?) 

in the past, 1 of the 3 speakers was louder sounding than the others. now the quiet designs have been boosted and are no longer quiet. they're super loud these days.


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## dreyn77

the more resistance the 'brighter' the tone. so the sound of the notes seem higher in pitch. the lower the ohm's the lower the tone of the notes. but even this aspect nolonger applies cause it's just another way for them to exployt the whole guitar buyers pockets of money. 

guys like leo fender were concerned with how a signal gets effect going through a pot. so he made his signal go through a pot in a different manner than what gibson did. all this stuff was important to the designers, but isn't worth thinking about for us guitar users.


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## dreyn77

have a listen to how dark kirks sound is and how bright michaels sound is. its what you're actually asking about.


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## GuitarMutant

dreyn77 said:


> have a listen to how dark kirks sound is and how bright michaels sound is. its what you're actually asking about.




Lulz... Seriously? There's a lot more, FAR more imperative, factors in the difference between Kirk's tone and Michael's than the impedance of their speakers. Different guitars, pickups, amps, tubes, pedals, players, speaker type, etc. 


Is there a difference in tone of different impedances? Sure, possibly. Nothing I've noticed. But I won't tell the people who hear a difference that they're nuts. It's quite possible because you're changing the flow of signal. But it's far from dramatic if it's there at all. You'll hear more differences in the year your speaker was made, or how well broken in it is.


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## Scumback Speakers

A few years back I did some tests with Dave Friedman using 8 ohm taps vs 16 ohm taps. We loaded two 4x12's with identical speakers (Scumback M75's), one at 8 ohm, one at 16 ohm. While we were doing it George Lynch was hanging around to listen as well. 

Dave & I tried each cab for about 5-10 minutes each with different guitars. What we heard was subtle, but the 8 ohm tap had a tiny bit more mids/aggression, and the 16 ohm tap had a little more bass with vintage feel to it. Many of the touring players I know swear by 8 ohm cabs, there are more who are happy with 16 ohm cabs. 

The tests were done with a Marshall amp that Dave had worked on and just serviced (100w JMP or Plexi, can't remember which right now) so we felt the amp was doing what it was supposed to and made a good test amp for the 8 ohm vs 16 ohm testing.

Bottom line: It's a subtle difference, and depending on your pedals/pickups/guitar it may or may not even be a factor. We just went guitar-> cable->amp->cab for our signal chain.

Hope that helps!

Jim


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## mickeydg5

I have posted comments about these types of comparisons before. An 8 ohm is not the same as 16 ohm even amongst the same model. There are minute differences between the two designs, enough to change some characteristics. Not all examples will exhibit the same types of differences. One model may exhibit added bass in a specific cabinet with a 16 ohm version while another model could be opposite having the 8 ohm version exhibit more bass. This can be seen by examining the speaker's separate specification/data sheets and Thiele/Small parameters for both the 8 ohm and the 16 ohm versions.

So everyone should look at specifications and parameters if available first.


Jim, do you have specification sheets and parameters for both the 8 ohm and 16 ohm versions of the M75 speakers (at the same wattage)?


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## Scumback Speakers

mickeydg5: No sir, I've never felt the need to do spec sheets for for thiele/etc parameters. I had a client who did this for a few of my speakers, and sent me the results (Scumnico SC75 and one other, I think the J75) but I'm afraid that was lost in an email database crash (thanks Microsoft) or hard disk failure and I can't find those now.

I did get a lot of help from various touring players (Kirk Fletcher for one) when I did my initial designs years ago, and I also enlisted the help of Orange County Speaker Repair for a number of things including testing of speakers, parts, and a cab software program for calculations of various cab sizes. Sadly OCSR closed their doors in April, so I can't get with them to use any of their resources.


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## mickeydg5

Yes, sorry to hear about Orange County.
That is alright. Most do not offer all of that information but it is handy if available. As Micky mentioned previously, people grab whatever suits the impedance situation best first. It ends up being plain trial and error or a coincidence that both/all versions are available for comparison.

Man, you got to back up them disk on another disk/computer.


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## Scumback Speakers

mickeydg5 said:


> Man, you got to back up them disk on another disk/computer.


Yeah, I did have them backed up on two different extra hard disks. Entourage/Outlook couldn't read it's own file to access it again. I just upgraded and the new version imported one archive twice, splitting the emails up at 2008-present (missing a bunch) and 2004-2008. It's a mess to sort, and I know it's not all there. 

I switched over to Apple Mail a few weeks back, and I'm going to cancel my Office 365 subscription.


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## dreyn77

Hey it's great now we've finally got scumback speakers here giving some good advice. 

Guitar mutant, it was just too tempting for you to instantly put up a opposite post to my post, in your view of things. 
Sure, my post clearly, in the extreme, points out the overall goal of exploiting electrics for guitarists. 
But did you notice how at the end of what they played, they both finished on the same chord and neither of them were IN TUNE. Hahaha! 
All of this TONE searching comes at the cost of being IN TUNE with other instruments. Jarring, horrible, nasty sounds are for those who are misfortunite enough to be in the room, listening to de-tuned & over- tuned electrical signals. 

Clearly a speaker at 16, and another speaker at 8, are basically two different speakers. The ohms have been manipulated already so to modding has already begun at that point. The mids sound is where it's got the most noticeable sound change. 
We can hear the difference in signal, but does it mean that we should let it effect us? 

Michael and kirk are clearly happy to be playing out of tune, so a small sound change in copper wire length, is not worth thinking about.


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## 30watt

dreyn77 said:


> Hey it's great now we've finally got scumback speakers here giving some good advice.
> 
> Guitar mutant, it was just too tempting for you to instantly put up a opposite post to my post, in your view of things.
> Sure, my post clearly, in the extreme, points out the overall goal of exploiting electrics for guitarists.
> But did you notice how at the end of what they played, they both finished on the same chord and neither of them were IN TUNE. Hahaha!
> All of this TONE searching comes at the cost of being IN TUNE with other instruments. Jarring, horrible, nasty sounds are for those who are misfortunite enough to be in the room, listening to de-tuned & over- tuned electrical signals.
> 
> Clearly a speaker at 16, and another speaker at 8, are basically two different speakers. The ohms have been manipulated already so to modding has already begun at that point. The mids sound is where it's got the most noticeable sound change.
> We can hear the difference in signal, but does it mean that we should let it effect us?
> 
> Michael and kirk are clearly happy to be playing out of tune, so a small sound change in copper wire length, is not worth thinking about.



Seriously, you are now ragging on two of the best-known metal guitarists in the world?


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## dreyn77

And just for giggles today, I plugged in the Gibson les Paul and adjusted thE amp to different settings and used the 1959RR in all ways I should and shouldn't and found there was only 1 EQ setting which made randy's 'Blizzard of ozz' sound. As I predicted it would be the case. 
AND I plugged in the Seymour Duncan designed Ritchie Blackmore strat and recklessly adjusted the amps E Q settings all over the place and discovered the Marshall was actually making sounds which are bent out of shape! 
Right at the most ideal amp settings too. 
Which ALL came from MY fingers! I'm too good! it seems. 

Ritchies settings turn out to be, presence '10', bass mids treble, '5'. 
Now who would have thought that! ? 

Only me. And I'm proven right once again.

The presence circuit on the 1959RR amp, just converts the sound from high impedance to low impedance. 
Cause ritchies pickups are maxed out low impedence designs, the amp must have the presence control maxed out. There you'll hear the sound of a giant stratocaster guitar. 
Once you know what these things are made from, which types of electrical circuits, the rest is easy. Adjusting the controls is SO simple! 

Plug the Blackmore strat into an amp made for some other purpose and you'll hear a massive tone power problem start to happen for you. 

By the way, burst buckers are NOT built for JMP style amps, they're for JCM 2000 type of amp styles.


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## mickeydg5

Is it safe to say all gear has differences?


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## 30watt

dreyn77 said:


> And just for giggles today, I plugged in the Gibson les Paul and adjusted thE amp to different settings and used the 1959RR in all ways I should and shouldn't and found there was only 1 EQ setting which made randy's 'Blizzard of ozz' sound. As I predicted it would be the case.
> AND I plugged in the Seymour Duncan designed Ritchie Blackmore strat and recklessly adjusted the amps E Q settings all over the place and discovered the Marshall was actually making sounds which are bent out of shape!
> Right at the most ideal amp settings too.
> Which ALL came from MY fingers! I'm too good! it seems.
> 
> Ritchies settings turn out to be, presence '10', bass mids treble, '5'.
> Now who would have thought that! ?
> 
> Only me. And I'm proven right once again.
> 
> The presence circuit on the 1959RR amp, just converts the sound from high impedance to low impedance.
> Cause ritchies pickups are maxed out low impedence designs, the amp must have the presence control maxed out. There you'll hear the sound of a giant stratocaster guitar.
> Once you know what these things are made from, which types of electrical circuits, the rest is easy. Adjusting the controls is SO simple!
> 
> Plug the Blackmore strat into an amp made for some other purpose and you'll hear a massive tone power problem start to happen for you.
> 
> By the way, burst buckers are NOT built for JMP style amps, they're for JCM 2000 type of amp styles.



And this rant has exactly what to do with speaker resistance???


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## mickeydg5

It is all about what he is thinking at the time. Have you not figured that out yet?


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## 30watt

Yes, quite.


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## BowerR64

If 2 speakers are identical one is 8 and one is 16ohms then what is it that makes them different? 

More windings, thinner wire or is it thicker wire and fewer windings?


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## danfrank

Traditionally, tube amps work more efficiently with higher ohm speakers/cabinets and solid state amps make more power output with lower ohm speakers/cabs. 16 ohms was the norm everywhere back in the 1950s because most everything was tube based. When solid state became the norm, lower ohm speakers became the norm also. Take car stereos for example... 4 ohms and even 2 ohms is commonplace now. It has to do with what works more efficiently with a given application. Vacuum tubes are more voltage devices whereas solid state is more current based.
Which sounds better? To each his own.
But there are subtle parameter differences between the 2 speakers.


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## dreyn77

My 45,000 friends want something to read, that's why!

Today I also learned that the modded channel on the 1959RR amp has the power to increase the bass tones dramatically! And not only that but the 2 volume adjustment feature allows a user to fully change the bass notes sound anyway you want them to sound.
No other marshall amp can do this for tones. So that section in the amp probably offers the user another 20 different sounds, with 1 pickup in use. So if you use 2 pickups, then 30 or more sounds are easily possible from that mod section alone.
The 1959RR amp is incredible!
This thread has had a great influence on me. I hope it does for you too!


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## EL 34

some say that 16 ohm wiring is tighter than the more open 4 ohm wiring sound.

this is basically from the 1959HW user manual.


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## Scumback Speakers

BowerR64 said:


> If 2 speakers are identical one is 8 and one is 16ohms then what is it that makes them different?
> 
> More windings, thinner wire or is it thicker wire and fewer windings?



The wire is a different gauge on an 8 ohm vs a 16 ohm voice coil. That's what makes the ohm rating different, at least on my voice coils. Physically they look the same, however.


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## BowerR64

And being a different gauge allows you to use more or less windings? 16 is more resistance so its probably a thinner gauge and more windings?


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## mickeydg5

It is all of the combinations; wire gauge, former diameter, number of wraps.

I sometimes hung out with a guy who rebuilt speaker systems. He liked to talk and show me things in his shop. I once had a vintage Jensen reconed but with 16 ohm voice coil. The first recone came out nice and sounded fine but I noticed (could feel) a slight rub at one end of its excursion. It bothered me because I knew it was there so I asked him to have a look. He decided to redo it and ordered a different voice coil. We determined that something was ever so slightly cocked enough to cause the rub and purposely made it mark before pulling things apart. We observed the mark, slightly angled at one end if the coil. He showed me the differences between the old and the new voice coils when it arrived. I believe the formers were the same diameter. The older coil had less wraps, a larger gauge and a DC resistance of about 13 ohms with the significant difference being a bit larger overall voice coil diameter. Now we are talking thousands of an inch here but enough to make the difference. The new coil had more wraps, smaller gauge, slightly less overall outside diameter and a DC resistance of about 16 ohms.


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## Shai`tan

I was using a single Scumback 8 ohm M75 65 watter in a Bogner Cube.... with my Rockitt Retro 50 watt Plexi Clone. Sounded amazing. But I ended up eventually blowing the voice coil. So
I bought another Bogner Cube, and ordered 2 Scumback M75 65 waters.... 16 ohm versions. The RR tap set at 8 Ohms. Not sure if it`s the fact I am using 16 ohm speakers with the 8 ohm
tap, or the fact that I am using 2 speakers instead of 1..... but I definitely hear the difference, and to my ears it is way more musical. I`m sticking with the 16 ohm versions. Thx again Jim @ Scumback!!! ;p


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## Scumback Speakers

Shai`tan said:


> I was using a single Scumback 8 ohm M75 65 watter in a Bogner Cube.... with my Rockitt Retro 50 watt Plexi Clone. Sounded amazing. But I ended up eventually blowing the voice coil. So
> I bought another Bogner Cube, and ordered 2 Scumback M75 65 waters.... 16 ohm versions. The RR tap set at 8 Ohms. Not sure if it`s the fact I am using 16 ohm speakers with the 8 ohm
> tap, or the fact that I am using 2 speakers instead of 1..... but I definitely hear the difference, and to my ears it is way more musical. I`m sticking with the 16 ohm versions. Thx again Jim @ Scumback!!! ;p


You are welcome, sir! Glad to hear you like the 8 ohm tap with the two 16 ohm M75's with your RR 50w.


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## scottbaierl

The lower the ohm rating, the more demand it places on your amplifier to drive it to the same volume level. Twice as much current will flow through an 8 ohm speaker than a 16 ohm speaker. The lower you go, the more heat is generated as well. This is just conjecture, but if there's a difference in tone or feel, it might be the fact that the amplifier is working so much harder to drive a lower ohm cab vs. a 16 ohm cab. I run my Super Leads with everything dimed, and they are already working hard and generate plenty of heat at 16 ohms. 8 ohms is still fine, but I would never go down to a 4 ohm load. Consequently, all my cabinets are of the 16 ohm variety.


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## mickeydg5

scottbaierl said:


> The lower the ohm rating, the more demand it places on your amplifier to drive it to the same volume level. Twice as much current will flow through an 8 ohm speaker than a 16 ohm speaker. The lower you go, the more heat is generated as well. This is just conjecture, but if there's a difference in tone or feel, it might be the fact that the amplifier is working so much harder to drive a lower ohm cab vs. a 16 ohm cab. I run my Super Leads with everything dimed, and they are already working hard and generate plenty of heat at 16 ohms. 8 ohms is still fine, but I would never go down to a 4 ohm load. Consequently, all my cabinets are of the 16 ohm variety.


That is not correct for tube amplifiers due to impedance matching output transformers. The tube amplifier is putting out the same power at any particular volume no mater which output impedance tap is being used. That is the transformers primary function.

Your description is more of a solid state power amplifier. It has been brought up many times in these forums.


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## scottbaierl

Doh... Right. So, the only time I am correct is when you don't match your amp's impedance with your cabinet...


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## mickeydg5

scottbaierl said:


> Doh... Right. So, the only time I am correct is when you don't match your amp's impedance with your cabinet...


Well, kind of. It is a give and take situation with a transformer. The power in ALWAYS equals power out. So the different secondary taps shift the voltage/current ratios.
16 ohm tap will have higher voltage and lower current levels while a 4 ohm tap will have lower voltage and higher current levels relative to the primary.


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## scottbaierl

Makes sense.


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## Webslinger

Maybe a little off-subject, but (way) back in the day...with CAR audio. Most factory stock systems were 4watts through a pair (or 2pair) of 8ohm speakers. So a quick & dirty improvement we would do was to swap the speakers with generic 4ohm'ers of the same size, from places like Radio Shack. The 4ohms were definitely perceived louder & clearer at the same volume level.

Now with guitar speakers, it's a whole different situation. We're dealing with much larger diameter cones, bigger magnets, and higher wattages. Perceived volume & tone, has more to do with elements like voice coil design, materials, Db sensitivity, etc. So I would think the 8 & 16 ohm standard choices are mainly for being able to match the correct loads for 2 or 4 speaker cabs, and dual cabs.


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## stacker22

I have just a bed room setup 
Bogner Shiva 6L6 combo 
Pushing 212 Marshall g12M 16 ohm each :
8 tap
& 
212 Eminence private jacks 8 ohm each:
4 tap 
Point being I have never had any problems knock on wood.


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## rom661

Scumback Speakers said:


> mickeydg5: No sir, I've never felt the need to do spec sheets for for thiele/etc parameters. I had a client who did this for a few of my speakers, and sent me the results (Scumnico SC75 and one other, I think the J75) but I'm afraid that was lost in an email database crash (thanks Microsoft) or hard disk failure and I can't find those now.
> 
> I did get a lot of help from various touring players (Kirk Fletcher for one) when I did my initial designs years ago, and I also enlisted the help of Orange County Speaker Repair for a number of things including testing of speakers, parts, and a cab software program for calculations of various cab sizes. Sadly OCSR closed their doors in April, so I can't get with them to use any of their resources.



I'm in high end audio and have designed hi-fi speakers for many years. T/S parameters are very important in a vented cabinet where accurate bass and extension is an issue but, with the typical high QTS of a driver in an open box or sealed box, I doubt that it matters much. I was surprised that the 16 ohm version wouldn't have more inductance and roll off the top end earlier but didn't realize you guys use different gauge wire. To me talking about two 8's in series is very different than the same design with a 16 ohm voice coil. You do have one in front of the other acting as an inductor in series and I would think that would change the response. The other variable would seem to be that if there is higher inductance on a 16 ohm single coil, the high output impedance of a typical tube amp is going to give you slightly more highs, rather than less on a SS amp. Some of that is conjecture on my part.


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## SG~GUY

-cool retro-thread!!.. and today the speaker data sheets prove there's a difference in V-30's-(I believe they were the MESA proprietarie)-

-I'm a believer, I have some 16 ohm-(England)-75hz, GREENBACK's-(I got a big pile of 1777 & 6402 coned GREENBACKS)- I would love to trade for some current production 8ohm, 55hz greenbacks... 

-JUST SAYIN-


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## BowerR64

what about wire cooling? wouldnt fewer windings of a larger gauge be more reliable for a LOUD live rig that would see high power for hours and not have issues?

I think ide prefer fewer windings of a heavier gauge on the coil.

But then a thinner gauge might be lighter and more responsive and snappy?


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## Micky

BowerR64 said:


> what about wire cooling? wouldnt fewer windings of a larger gauge be more reliable for a LOUD live rig that would see high power for hours and not have issues?
> 
> I think ide prefer fewer windings of a heavier gauge on the coil.
> 
> But then a thinner gauge might be lighter and more responsive and snappy?


The same amount of power will generate the same amount of heat, so it then becomes a function of how quickly the heat is dissipated from the coil.

Generally the impedance of a cab is dictated more by convenience than anything else, a 16-ohm cab is more easily paralleled with other cabs and amps than lower impedance stuff.


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## mickeydg5

I think Bower64 just described a lower impedance voice coil versus a higher impedance one.


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## brian zimmerman

I have a 2x12 cabinet and the speakers in the cab are both 8ohm speakers, do I use a head that is 16 ohms or 8ohms?


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## Jon C

brian zimmerman said:


> I have a 2x12 cabinet and the speakers in the cab are both 8ohm speakers, do I use a head that is 16 ohms or 8ohms?


It depends on whether they are wired in series or in parallel ……


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## brian zimmerman

meaning 16om head for in series and parallel for 8ohm head?


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## paul hancher

all i can offer is real world observations made with amps that i have owned. 

some of my guitar amps sound different when you change the ohm setting, others do not, all other variables being equal. usually running at 16 ohms will decrease the volume slightly, but make the tone more crisp, with an increased presence boost which i think sounds good.

examples:

my current ceriatone white bassman clone sounds the same when run thru an 8 ohm speaker at 4, 8 and 16 ohms.

my origin 50h sounds different when run at 16 ohms vs. 8 ohms in the manner that i described above. 

i once had a russian red bear 50 watt combo where the ohm selector was a 3 way sliding switch. not only did it sound better on the 16 ohm setting, you could position the switch in between the settings like you can with a vintage 3 way strat switch. the best sounding setting was between 8 and 16 ohms. i am guessing that set the ohms at somewhere around 12 ohms.


----------



## mickeydg5

brian zimmerman said:


> I have a 2x12 cabinet and the speakers in the cab are both 8ohm speakers, do I use a head that is 16 ohms or 8ohms?


Is the cabinet marked with its impedance rating?

If not then you have to look at the wiring and it always helps to measure resistance of the speakers and circuit to be sure of things.


----------



## BowerR64

mickeydg5 said:


> I think Bower64 just described a lower impedance voice coil versus a higher impedance one.



The question was why choose one over the other and that was what i was trying to point out.

If one speaker say the 8 ohm had less windings with a thicker gauge wire on the coil over more windings on the coil with thinner wire i think ide want which ever stays cool during high power for longer periods.

I would think a hot coil would sound sloppy and loose and a cool one would sound more tight and articulate?

but its all just guessing on my part


----------



## BowerR64

mickeydg5 said:


> I think Bower64 just described a lower impedance voice coil versus a higher impedance one.



The question was why choose one over the other and that was what i was trying to point out.

If one speaker say the 8 ohm had less windings with a thicker gauge wire on the coil over more windings on the coil with thinner wire i think ide want which ever stays cool during high power for longer periods.

I would think a hot coil would sound sloppy and loose and a cool one would sound more tight and articulate?

but its all just guessing on my part


----------



## mickeydg5

BowerR64 said:


> The question was why choose one over the other and that was what i was trying to point out.
> 
> If one speaker say the 8 ohm had less windings with a thicker gauge wire on the coil over more windings on the coil with thinner wire i think ide want which ever stays cool during high power for longer periods.
> 
> I would think a hot coil would sound sloppy and loose and a cool one would sound more tight and articulate?
> 
> but its all just guessing on my part


There is no real wieght difference for carry ability between a 16 ohm and 8 ohm coil. That is far less than an ounce.
The choice for coils is for mixing and matching multiple or sets of speakers.

It also depends on impedance matched outputs versus normal minimal impedance outputs.

As Micky mentioned earlier the heat is equated to how much power is dropped at the speaker whether 16 or 8 ohms. 30 watts at either impedance produces the same heat theoretically.


----------



## Tihomir Stoyanov

Good day, djents!

I am an electrical architect for the last 3 decades since i made my first amp when I was 7yo. By call. 
The advantage of having 16ohm over 8ohm speaker is that the THD is somewhat less. Because of the inherent architecture of a class A and AB amps (which are best quality and mostly used by djents like us), reducing the load of the amp (using smaller ohm speaker) is doing two things. Firstly, less resistance means more current flow and more magnetic force generated at the voice coil, other words - louder. But also this increases the distortion of the channel. See the datasheet of LM4780. I used this as part of an old project. Look for the graphics of THD vs frequency. They are given for 4, 6 and 8ohms of load, but nevertheless, clearly you can see the tendency of reducing the THD with increasing the resistance of the speaker. Simply put: 8ohms should be a bit louder, but not so clean, 16ohms should be a bit softer, but more clarity. The rest is highly subjective, as you all have different amps with different architectures and so on. 
I hope I was helpful. Just don't forget the basic rule never to connect lower impedance to any amp then its design. This would very probably lead to arising the urgent need for bying a new amp....


----------



## South Park

The output transformer windings on the secondary’s controls the power to the speaker so the power tubes see the same thing on all ohm setting .


----------



## Gutch220

pedecamp said:


> If my amp has the ability to plug into it a 16 Ohm or 8 Ohm speaker, why would I choose one over the other? Advantages? Disadvantages?
> 
> I've heard some people say it doesnt matter, and others say one has better response over the other. I just dont know. Lets hear what everybody has to say at Marshall Forum


Because it gives you flexibility, some people have one or the other. Plus it gives you the option to use two 16ohm speakers. Or four 32 ohm speakers should the need arise. Or eight 64 ohm speakers. or sixteen 128 ohm speakers.


----------



## El Marin

My small experience

-Marshall Origin 50 H
-Marshall 1922 (G12-75 whitelabel 16 Ohms + English Vintage30 16 Ohms)

The cab can go 8 Ohms mono or both 16 oms stereo

I plugged it one cable 8 Ohms and then two cables 16 Ohms.

Even the DRUMMER said it was better at 16 Ohms stereo. Less compressed.

But is subtle nevertheless


----------



## RLW59

El Marin said:


> My small experience
> 
> -Marshall Origin 50 H
> -Marshall 1922 (G12-75 whitelabel 16 Ohms + English Vintage30 16 Ohms)
> 
> The cab can go 8 Ohms mono or both 16 oms stereo
> 
> I plugged it one cable 8 Ohms and then two cables 16 Ohms.
> 
> Even the DRUMMER said it was better at 16 Ohms stereo. Less compressed.
> 
> But is subtle nevertheless



The impedance was 8 ohms either way. One single speaker is 16 ohms, but if you use two cables and plug them into the amp's parallel outputs, all you did was move the parallel connection from the cab's jacks to the amp's jacks.

If it sounded different, there may be a problem with the cab's switching jacks.


----------



## El Marin

RLW59 said:


> The impedance was 8 ohms either way. One single speaker is 16 ohms, but if you use two cables and plug them into the amp's parallel outputs, all you did was move the parallel connection from the cab's jacks to the amp's jacks.
> 
> If it sounded different, there may be a problem with the cab's switching jacks.



What you say seems right and logic. If it is that way, It should sound exactly the same

I will check that


----------



## mickeydg5

Your speaker cables would have to be identical twins. The jacks would have to be too.
Most people do not go into depth with cables and jacks but a simple dirty contact or solder connection at the cable or jack can make a significant difference in output sound.

Not all cable are created equal nor remain equal.


----------



## Till

Tihomir Stoyanov said:


> Good day, djents!
> 
> I am an electrical architect for the last 3 decades since i made my first amp when I was 7yo. By call.
> The advantage of having 16ohm over 8ohm speaker is that the THD is somewhat less. Because of the inherent architecture of a class A and AB amps (which are best quality and mostly used by djents like us), reducing the load of the amp (using smaller ohm speaker) is doing two things. Firstly, less resistance means more current flow and more magnetic force generated at the voice coil, other words - louder. But also this increases the distortion of the channel. See the datasheet of LM4780. I used this as part of an old project. Look for the graphics of THD vs frequency. They are given for 4, 6 and 8ohms of load, but nevertheless, clearly you can see the tendency of reducing the THD with increasing the resistance of the speaker. Simply put: 8ohms should be a bit louder, but not so clean, 16ohms should be a bit softer, but more clarity. The rest is highly subjective, as you all have different amps with different architectures and so on.
> I hope I was helpful. Just don't forget the basic rule never to connect lower impedance to any amp then its design. This would very probably lead to arising the urgent need for bying a new amp....



I was searching for this topic and just sign up to say thank you for the very competent answer. 
So my Harley Benton Tube 15 will get a 16Ohm Creamback (not 8). 

Till


----------



## CityguyUSA

I'm really starting to hate the tech world it's becoming so overly hard to know how to hookup one thing to another with HDMI 1 2 3 orv whatever version we're on now, USB 2.0 or 3.0 and plug ends of a 1000 types. I had to replace a hard drive the other month and it wouldn't detect the actual size of the disk. I was told because by the seller I didn't have a USB 3.0 connection powering the drive. That turned out to be wrong. The real problem was it needed to be connected to a sata connection don't ask which version I don't remember it took me a bit to figure out the problem.

Anyways a new flatscreen comes into the house and I decide that the bigger screen should go in the living room rather than my bedroom which has more wall space.

AT&T already destroyed the HDMI connection between my amp and my TV. Which caused my DTV to fail throughout the house and stop working except on the main screen and ultimately destroyed my account and my cost per month it all went whacky over an HDMI mismatch so I cut the cord.

Tonight I thought I'd hookup the new TV to the amp but the TV lists all the HDMIs as ins and yet they say in the docs that the HDMI(arc) can be used as an out. I tried various connections but no love yet.

As I was doing this I was reminded about ohms and impedence and when I bought the amp a while back it wasn't even listed in the ad and it's so involved assuring that you have the correct connections for everything I never thought about it until tonight. My amp says any speaker beteeen 6 & 16 ohms. I never heard of a range before but I went to check my speakers which are 20 some years old and they also list a range. Not what I was expecting. My last receiver was only listed at 8 ohms as I recall my speakers are 4 to 8 ohms. There's a 2 ohm miss on the low end and and 8 ohm miss at the high end. That doeen't even address the 2 rears which I think are 4 ohms. I have to look tomorrow.

I hear what you are saying about various sounds are at different hertz and ohms although it's a hard concept to grasp as to how that started the whole pairong of speakers with what used to be matching ohms. And that less resistance will allow more power to flow.

But what should I be buying? Should I go for higher ohms because it doesn't take as much power to output the sound or is that higher resistance going to distort quicker because you don't have the power to reproduce those lower sounds?

And then how do I navigate the shifted ranges between my speakers and my amp? I could add a speaker in parallel to increase each channel from the 4 ohms to 6+ ohms and similarly if I find out that my rears are strictly 4 ohms I could do the same to increase the resistance or I could just replace them with 6 to 16 ohm speakers to match the amp but them when I get a new amp is it going to be 16 to 32 ohms and why are they usualky inn multiples of 4 excluding my dumb amp with it's 6 ohm starting point? What about wire length resistance do we not care?


----------



## SkyMonkey

Is this a copy/paste from a HiFi forum?


----------



## tschrama

Tihomir Stoyanov said:


> Good day, djents!
> 
> I am an electrical architect for the last 3 decades since i made my first amp when I was 7yo. By call.
> The advantage of having 16ohm over 8ohm speaker is that the THD is somewhat less. Because of the inherent architecture of a class A and AB amps (which are best quality and mostly used by djents like us), reducing the load of the amp (using smaller ohm speaker) is doing two things. Firstly, less resistance means more current flow and more magnetic force generated at the voice coil, other words - louder. But also this increases the distortion of the channel. See the datasheet of LM4780. I used this as part of an old project. Look for the graphics of THD vs frequency. They are given for 4, 6 and 8ohms of load, but nevertheless, clearly you can see the tendency of reducing the THD with increasing the resistance of the speaker. Simply put: 8ohms should be a bit louder, but not so clean, 16ohms should be a bit softer, but more clarity. The rest is highly subjective, as you all have different amps with different architectures and so on.
> I hope I was helpful. Just don't forget the basic rule never to connect lower impedance to any amp then its design. This would very probably lead to arising the urgent need for bying a new amp....



But we are talking about guitar amps, with tubes, output transformers and love distortion


----------



## SkyMonkey

A Google search with sections of text show it's all original!

I am sorry @CityguyUSA, but you seem to have us confused with a Home Cinema forum.
Very extensive and thorough first post though.

Do you play guitar?


----------



## Doug S.

Hello,

My first post, currently don't own a Marshall amp but want to thank thread participants for clearing up things I've wondered about for years regarding how 4, 8 and 16 ohm loads interact with amps and how it might impact tone. There is surprisingly little informed discussion regarding this subject online.

Doug


----------



## SkyMonkey

Welcome to the MF @Doug S.


----------



## JBA

pedecamp said:


> If my amp has the ability to plug into it a 16 Ohm or 8 Ohm speaker, why would I choose one over the other? Advantages? Disadvantages?
> 
> I've heard some people say it doesnt matter, and others say one has better response over the other. I just dont know. Lets hear what everybody has to say at Marshall Forum


I’d pick a 16ohm cab leaving me the possibility of a second cab in the future. There are other more complex (specific) scenario’s I can help with if you have a want to let say have 3 speakers, or control the balance of volume between certain speaker/cab combinations etc...

Now hold my beer... I’m about to challenge some of the “interesting” advice you have received in past post. ;-)


----------



## Crikey

manktelow said:


> I like this argument. There are many people on the forum that have been playing electric guitar for decades. Plus all the players that they have met. If there was an Ohm setting that sounded the best, it would be common knowledge by now.


I pay no mind to those settings. Plug and play. I just stay off of four


----------



## JBA

chuckharmonjr said:


> Two identical cabs, both with say greenies...or g12m-70's...or whatever...but identical except one cab is 8 ohm the other is 16...there is zero difference between the two cabs so long as you match the amp's impedance to the cab. As far as OT winding, you are just changing the amount of winding engaged so to speak to limit the power output exposure of the power tubes to be the same at a given impedance.


Well.... we can say they are very similar. An 8 ohm equivalent model in 16 ohms is not the same speaker by design. They use almost every same component therefore they sound very close. Some test very close to each other and some models are a little further apart (but not sounding like a completely different model). Also due to the design and interaction of the output transformer you can notice the 16 ohm usually has a bit more upper and lower frequency extension. For this reason ( if you are a very fussy guy) I recommend an 8 ohm for really fizzy amps and 16 ohm for a mid strong amp. But all and all, just pick for flexibility and use the knobs on your amp to address this much more effectively. ;-)


----------



## JBA

Scumback Speakers said:


> A few years back I did some tests with Dave Friedman using 8 ohm taps vs 16 ohm taps. We loaded two 4x12's with identical speakers (Scumback M75's), one at 8 ohm, one at 16 ohm. While we were doing it George Lynch was hanging around to listen as well.
> 
> Dave & I tried each cab for about 5-10 minutes each with different guitars. What we heard was subtle, but the 8 ohm tap had a tiny bit more mids/aggression, and the 16 ohm tap had a little more bass with vintage feel to it. Many of the touring players I know swear by 8 ohm cabs, there are more who are happy with 16 ohm cabs.
> 
> The tests were done with a Marshall amp that Dave had worked on and just serviced (100w JMP or Plexi, can't remember which right now) so we felt the amp was doing what it was supposed to and made a good test amp for the 8 ohm vs 16 ohm testing.
> 
> Bottom line: It's a subtle difference, and depending on your pedals/pickups/guitar it may or may not even be a factor. We just went guitar-> cable->amp->cab for our signal chain.
> 
> Hope that helps!
> 
> Jim


What you guys heard is absolutely correct and it’s due to the interaction of the 16ohm speaker with its high transformer tap vs the 8ohm with its lower impedance matching tap.


----------



## JBA

mickeydg5 said:


> I have posted comments about these types of comparisons before. An 8 ohm is not the same as 16 ohm even amongst the same model. There are minute differences between the two designs, enough to change some characteristics. Not all examples will exhibit the same types of differences. One model may exhibit added bass in a specific cabinet with a 16 ohm version while another model could be opposite having the 8 ohm version exhibit more bass. This can be seen by examining the speaker's separate specification/data sheets and Thiele/Small parameters for both the 8 ohm and the 16 ohm versions.
> 
> So everyone should look at specifications and parameters if available first.
> 
> 
> Jim, do you have specification sheets and parameters for both the 8 ohm and 16 ohm versions of the M75 speakers (at the same wattage)?


Nailed it!


----------



## JBA

Scumback Speakers said:


> The wire is a different gauge on an 8 ohm vs a 16 ohm voice coil. That's what makes the ohm rating different, at least on my voice coils. Physically they look the same, however.


Yep, 8 ohm heavier gauge and less turns than the 16ohm... or 16 gauge has lighter gauge with more turns, however you want to look at it. The coils are very close but have very slight different weights although the electrical parameters are different and they interact with the mechanical parameters. All this equals some small tonal differences, some more and some less affected by a given enclosure.


----------



## JBA

scottbaierl said:


> The lower the ohm rating, the more demand it places on your amplifier to drive it to the same volume level. Twice as much current will flow through an 8 ohm speaker than a 16 ohm speaker. The lower you go, the more heat is generated as well. This is just conjecture, but if there's a difference in tone or feel, it might be the fact that the amplifier is working so much harder to drive a lower ohm cab vs. a 16 ohm cab. I run my Super Leads with everything dimed, and they are already working hard and generate plenty of heat at 16 ohms. 8 ohms is still fine, but I would never go down to a 4 ohm load. Consequently, all my cabinets are of the 16 ohm variety.


You should add “when using a lower tap” before all this.. and it’s actually root 2 (1.414) times the current. If you use the proper tap, the amp does not work harder at 4 ohms than 16 ohms.. this is a myth.


----------



## JBA

rom661 said:


> I'm in high end audio and have designed hi-fi speakers for many years. T/S parameters are very important in a vented cabinet where accurate bass and extension is an issue but, with the typical high QTS of a driver in an open box or sealed box, I doubt that it matters much. I was surprised that the 16 ohm version wouldn't have more inductance and roll off the top end earlier but didn't realize you guys use different gauge wire. To me talking about two 8's in series is very different than the same design with a 16 ohm voice coil. You do have one in front of the other acting as an inductor in series and I would think that would change the response. The other variable would seem to be that if there is higher inductance on a 16 ohm single coil, the high output impedance of a typical tube amp is going to give you slightly more highs, rather than less on a SS amp. Some of that is conjecture on my part.


The transformer has better coefficient of coupling on the 16ohm tap then the 4 ohm tap, thus the wider bandwidth you can hear (and measure). ;-)


----------



## JBA

BowerR64 said:


> what about wire cooling? wouldnt fewer windings of a larger gauge be more reliable for a LOUD live rig that would see high power for hours and not have issues?
> 
> I think ide prefer fewer windings of a heavier gauge on the coil.
> 
> But then a thinner gauge might be lighter and more responsive and snappy?





BowerR64 said:


> what about wire cooling? wouldnt fewer windings of a larger gauge be more reliable for a LOUD live rig that would see high power for hours and not have issues?
> 
> I think ide prefer fewer windings of a heavier gauge on the coil.
> 
> But then a thinner gauge might be lighter and more responsive and snappy?


4 ohm, less turns, bigger gauge.
16 ohm, more turns, smaller gauge.

In the end, it’s close to the same mass and surface area the way it’s wound. Nothing comes for free in our physical world! Look only to the watt rating if you want more electrical power handling.


----------



## JBA

brian zimmerman said:


> I have a 2x12 cabinet and the speakers in the cab are both 8ohm speakers, do I use a head that is 16 ohms or 8ohms?


16 if they are wired in series, 4 if they are wired in parallel (or re-wire to 16... which it likely already is)


----------



## paul-e-mann

JBA said:


> I’d pick a 16ohm cab leaving me the possibility of a second cab in the future. There are other more complex (specific) scenario’s I can help with if you have a want to let say have 3 speakers, or control the balance of volume between certain speaker/cab combinations etc...
> 
> Now hold my beer... I’m about to challenge some of the “interesting” advice you have received in past post. ;-)


I asked this question 10 years ago! I've come to the conclusion it doesnt matter except for what you said about a 2nd cab.


----------



## JBA

Tihomir Stoyanov said:


> Good day, djents!
> 
> I am an electrical architect for the last 3 decades since i made my first amp when I was 7yo. By call.
> The advantage of having 16ohm over 8ohm speaker is that the THD is somewhat less. Because of the inherent architecture of a class A and AB amps (which are best quality and mostly used by djents like us), reducing the load of the amp (using smaller ohm speaker) is doing two things. Firstly, less resistance means more current flow and more magnetic force generated at the voice coil, other words - louder. But also this increases the distortion of the channel. See the datasheet of LM4780. I used this as part of an old project. Look for the graphics of THD vs frequency. They are given for 4, 6 and 8ohms of load, but nevertheless, clearly you can see the tendency of reducing the THD with increasing the resistance of the speaker. Simply put: 8ohms should be a bit louder, but not so clean, 16ohms should be a bit softer, but more clarity. The rest is highly subjective, as you all have different amps with different architectures and so on.
> I hope I was helpful. Just don't forget the basic rule never to connect lower impedance to any amp then its design. This would very probably lead to arising the urgent need for bying a new amp....


Being an “architect”? should also know that all these tube amp outputs are isolated with an impedance matching transformer which by virtue negates the load mismatch effects you have mentioned here.


----------



## JBA

tschrama said:


> But we are talking about guitar amps, with tubes, output transformers and love distortion


Yep, something tells me he wants to omit our gain stages lol. Joking, all in good fun of course!


----------



## JBA

pedecamp said:


> I asked this question 10 years ago! I've come to the conclusion it doesnt matter except for what you said about a 2nd cab.


Right on! These posts are timeless and so many folks turn to them for help and so the odd time the mood hits me to help separate fact from science fiction haha!

cheers brother!


----------



## Marshallmadness

I just had quite the revelation recently. I just assembled a B cab with four of my 8ohm 6402 cone greenbacks wired in parallel/series configuration and 8ohm. My other cab is a A cab with 16ohm 1777 cone greenbacks and 16ohm. Both cabs sound awesome and greenback all the way but they do not sound the same and the difference is pretty pronounced. The B cab is quite a bit cleaner, deeper, darker, tighter, and a different low end growl with more low end. It absolutely rules for metal. 

I don’t know exactly what has caused so much difference but there is quite a difference between the two cabs. I don’t think the 6402 8ohm and 1777 16ohm sound exactly the same either. That was a observation I noticed years ago swapping those speakers around in my combo amps but never really gave it much thought. Once both types where in cabs the difference became very pronounced. Both sound great but I was surprised to hear quite a difference comparing both cabs with my JMP2203 and a JCM2204.


----------



## ~Jason~

When taking just the speaker into consideration, there does appear to be a subtle tone difference between 2 versions of the same speaker, one wired 8 ohm (heavier gauge and less turns) and the other 16 ohm (lighter gauge with more turns). While testing, I noticed the biggest difference in tone & feel came more from which tap I used on the amp.

One test consisted of taking the actual speaker out of the equation. I wanted to test the behavior of the amp’s outputs. I used a reactive load box (UAD OX):

Configuration A:
Amp’s 4 ohm speaker output into UAD OX set at 4 ohm

Configuration B:
Amp’s 8 ohm speaker output into UAD OX set at 8 ohm

Configuration C:
Amp’s 16 ohm speaker output into UAD OX set at 16 ohm.

The 4 ohm tap sounded tighter/more compressed and slightly dull. The 16 ohm tap sounded more open with top end clarity. The sound & feel of the 8 ohm tap was somewhere in the middle, best of both. I typically prefer the 8 ohm tap for my standard tone, but have used the other configurations as well to add different tone characteristics when recording guitar tracks. Running two 8 ohm cabinets parallel with the 4 ohm tap is some heavy desert tone goodness.

All that said, the behavior could just be a result of how my amp is designed. I get the same results as my test using real cabs. Other amps may react different. Regardless, go with what sounds best to you based on the tone you’re going for at that time. Try to avoid amp/cab impedance mismatches.


----------



## DreamerDeceiver

What if I wanted to add a 3rd cab? 412 -16 ohm, to the full stack?(16 ohm spk in all)
Would it be wired the same, Parallel?
Would all 3 cabs still be 8 ohm?
How would the cabs be plugged in,......seeing they all have single mono jacks?

Thanks


----------



## ~Jason~

DreamerDeceiver said:


> What if I wanted to add a 3rd cab? 412 -16 ohm, to the full stack?(16 ohm spk in all)
> Would it be wired the same, Parallel?
> Would all 3 cabs still be 8 ohm?
> How would the cabs be plugged in,......seeing they all have single mono jacks?
> 
> Thanks




The Weber Z-Matcher is a good tool for allowing you to you run various cab impedances (2, 2.6, 4, 5.3, 8, 16) with your amp. On the Z-Matcher, set the amp knob to match the speaker output that you are plugged into on the amp and set the speaker knob to match what ever the total impedance is of the combined speaker cab setup. To run all 3 cabs in parallel it does require two of the cabs to have 2 jacks. Place the mono jack cab last in the chain. Three 8 ohm cabs in parallel would be 2.6 ohms. Three 16 ohm cabs in parallel would be 5.3 ohms. Two 16 ohm cabs and one 8 ohm cab in parallel would be 4 ohms.

If your cabs only have a mono jack you could try a Radial Cab-Link or something similar. The Cab-Link has 2 speaker outputs. It would allow you to run 2 mono jack cabs with your amp in either a series or parallel config.


----------



## DreamerDeceiver

Thanks.
I believe my 1960 b has a dual jack, and my jcm800ls Acab has the mono. Chances are if I obtain the 3rd 412 it will be a Bcab as well so it should have a dual jack..
Though it might be more cost effective to just get an attenuator ...solves both my issues,of additional cabs and low volume playing.
JCM900(93) ( 4/16 -8 )switch


----------



## RLW59

DreamerDeceiver said:


> Thanks.
> I believe my 1960 b has a dual jack, and my jcm800ls Acab has the mono. Chances are if I obtain the 3rd 412 it will be a Bcab as well so it should have a dual jack..
> Though it might be more cost effective to just get an attenuator ...solves both my issues,of additional cabs and low volume playing.



Three 16 ohm cabs is 5.33 ohms.

What amp do you have/what outputs does your amp have?

If it has a pair of jacks with an ohm selector switch with a 4 ohm setting, the 4 ohm setting is a safe mismatch with three 16 ohm cabs.

If your amp has the modern Marshall 5 output jacks, you can plug one 16 ohm cab into one of the 8 ohm outputs, and the other two 16 ohm cabs into the pair of 4 ohm outputs, and that will give you a perfect impedance match. (Yes it sounds crazy, but I didn't get the numbers backwards -- we can explain it further if that's the type of amp you have.)

Some Marshall amps only have 8/16 outputs. Three 16 ohm cabs would be a stressful mismatch for those amps.
---------------------------
No stock Marshall 1960 has dual parallel jacks. Older ones have single jacks, newer ones have switching jackplates that give 4 ohms or 16 ohm mono, or stereo each side 8 ohms. The switching jackplates have two jacks, but they _cannot _be used for in/out daisy chaining. (In mono mode using all 4 speakers you can only use 1 jack at a time.)


----------



## Scumback Speakers

Ok, I didn't realize this necro thread got revived from 5 years ago. A couple of observations that were determined years ago by Dave Friedman, George Lynch, Roy Blankenship and myself when testing identical 4x12's, one with 8 ohm M75's, and one with 16 ohm M75's.

1) The 16 ohm tap has more bass, and vintage feel. The 8 ohm tap has more mids and is slightly more aggressive in the upper mids. Hence the 8 ohm tap is brighter since it has more upper mids than the 16 ohm tap.

2) Voice coils are wound to a "spec". The mass/size/etc have to be very close to fit in the voice coil gap of the frame. The 8 ohm uses slightly thicker wire, 16 ohm uses thinner wire since it needs more winds.

3) It takes more power to push a 16 ohm cab/speaker than an 8 ohm. If I set the variac (or any amp in my pile) to 16 ohms, and then use it with an 8 ohm cab at the same volume, the 8 ohm cab is louder. How much? Varies with the output tranny, but typically 5-8w louder on a 100w head, 4-5w louder on a 50w Marshall head...roughly.

Any differences we heard between amps was attributed to the output tranny. Once you put two 16 ohm cabs to an amp, you have to set the output to 8 ohms, and the single cab results go out the window since you now have 8 speaker cones moving versus 4 cones moving.

Now, keep in mind, the four of us in that room probably had enough real world stage, studio, amp making and listening skills to come up with what I listed above.

Your mileage may vary.

Jim


----------



## RLW59

DreamerDeceiver said:


> What if I wanted to add a 3rd cab? 412 -16 ohm, to the full stack?(16 ohm spk in all)
> Would it be wired the same, Parallel?
> Would all 3 cabs still be 8 ohm?
> How would the cabs be plugged in,......seeing they all have single mono jacks?
> 
> Thanks



This really should be a separate thread. Or a necro-bump of one of the threads where we talked about three 16 ohm cabs (or an 8 and 16 together -- electrically the same thing).


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## JBA

-For a given speaker model, the 16 ohm and 8 ohm versions are not 100% identical and thus will have some very small frequency response differences.

-16 ohm speakers DO NOT take more power to push than 8 ohm speakers. Simply a higher voltage and lower current ratio is the result which still multiply out to the same Wattage and thus efficiency.

-the 16ohm tap (on a multi tap transformer) has a better coefficient of coupling than its 8 ohm tap and even more so than its 4 ohm tap just by physical design so:

1. a 16 ohm cab on a 16 ohm tap will have a wider bandwidth meaning you will notice more of the very high frequencies come through, than an identical 4 ohm wired cab on the 4 ohm tap. (This can be best demonstrated on a 2x12” with 8 ohm speakers that can be wired either at 4 or 16 ohms.

2. Does one sound better than the other, well yes, if you use this knowledge to filter out unwanted top end by going 4 ohms, or if you need more extension then wire for 16ohms. It depends your preference, the amp, the guitar, and the cab for YOUR situation.

3. Mismatch loads can also have the same high pass effect as mentioned above. First, I don’t recommend you do it unless you completely understand the math and amp limits here or put your trust into some stranger like me who tells you they know what they are doing and gives you their “safe” mismatch advice. 
a) In this case, higher impedance on lower impedance tap will extend the high end response.
B) Lower impedance speaker on high impedance tap will narrow the frequency response.

But don’t do it, you have a presence adjustment on the amp.. use it!


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## matttornado

I always set my Superlead to 8 ohms with a 16 ohm 4x12 . It makes a difference and sounds better to me; more compressed maybe, less harsh, smoother?

With my 2x12 / 8 ohm Avatar cab, I use 8 ohm amp setting & it sounds great so I basically leave my head set at 8 ohms regardless of what cab I use.


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## JBA

matttornado said:


> I always set my Superlead to 8 ohms with a 16 ohm 4x12 . It makes a difference and sounds better to me; more compressed maybe, less harsh, smoother?
> 
> With my 2x12 / 8 ohm Avatar cab, I use 8 ohm amp setting & it sounds great so I basically leave my head set at 8 ohms regardless of what cab I use.


Yep, the added bass and high extension give just a tad bit more of that “hifi” sound which matches well to mid focused amps.. with the opposite being true with modern more “fizzy” type amps and speakers. Just got to keep under 3/4 output (not volume position) and you’ll be ok, but something tells me you likely know this already. Cheers


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## James Freeman

george76 said:


> there is a difference in tone between 8 Ohm and 16 Ohm speakers but it is usually only very marginal. nothing worth losing any sleep over. although i do know one guy who swears by 8 ohm speakers, he says they have more bass.
> 
> here is an old post by duncan boniface on the plexi forum (the original dr.decibel)
> 
> *"usually the difference between 8 and 16 ohms is the wire gauge and number of turns on the coil. All else is usually left identical, including the 'winding length' (distance from the top of the wind to the bottom). *
> 
> *16 ohm coils use thinner wire, and more turns to get the higher impedance compared to 8 ohms. *
> 
> *USUALLY (nothing is set in stone) the 8 ohm will be a little more solid and forceful in sound, with a bit more warmth. The 16 ohm will be a little thinner and more 'airy' in sound. *
> 
> *HOWEVER..... it's all about compromise and interaction. For a given coil diameter and winding length, you will usually choose between 2 or 3 wire guages that will fit the nominal spec. A 16 ohm coil may be as low as 11ohms DC resistance, it may be as high as 16ohm. the different wire gauges will have different numbers of turns, different weight, different inductance and different DCR. All these things have an effect, though subtle. I usually go for making the 16 ohm as close as I can to twice the 8 ohm DCR, but there will always be a choice as to whether it's the one above or the one below you pick. *
> 
> *Then we come to interaction with your amp ; the tone and feel of the bass is affected a lot by output damping. This is determined by the ratio of speaker and output TX impedances. As with the speakers, there will be some variation in the output TX windings from amp to amp, and so how these interact with the variation in speakers. *
> 
> *There may be virtually no noticeable difference between 8 and 16 ohm versions if the 8 ohm is very high DCR and the 16 very low, but if they're at either ends of the scale then the difference could be quite obvious. *
> 
> *The usual rule of thumb is called 'shove' and defined as (Bl)squared/Re where *
> *B = flux density in the gap (constant between 8 and 16 ohm, as they use the same magnet assembly) *
> *l = length of wire within the magnetic field (not all the wire, just that within the field) *
> *Re = DC resistance of coil *
> 
> *Higher shove means louder, more solid and forceful sound. *
> *As you can see, it's a balancing act. As impedance goes up, re and l both increase, but have opposite effects and depending on coil size and wind length one or other will dominate. *
> 
> *Use your ears. They don't care about the maths and make better decisions !"*



After some googling I find this quoted reply in blue the most relevant to the question.
Thanks to george76 for keeping this information from Dr.Decibel.

I was trying to find a clear answer regarding the speaker tonal difference between 8 and 16 ohm, without the output transformer taps replies people usually give.


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## JBA

James Freeman said:


> After some googling I find this quoted reply in blue the most relevant to the question.
> Thanks to george76 for keeping this information from Dr.Decibel.
> 
> I was trying to find a clear answer regarding the speaker tonal difference between 8 and 16 ohm, without the output transformer taps replies people usually give.


There are small tonal differences between 8 and 16 ohm speakers. The tap interaction also is legit. Here’s the thing.. let say the 16 ohm of a specific speaker model has a slight cut in a band vs the 8 ohm is this good or bad? Depends on your amp and speaker setup. That might improve or make things worse for YOUR amp and YOUR ears (on any given day). If you have lots of experience with speakers use it to your advantage, if you don’t, you won’t be able get what you need on a forum or YouTube video to help you figure which one will work for you. You basically need to try an A / B test yourself. From experience, it’s basically a waist of time if you don’t have a bunch of speakers lying around already. ;-)

Guys, don’t sweat this difference, you have tone controls and guitar tone and volume. You know the pots on the front of each amp have a greater variance than this 8 ohm vs 16 ohm conundrum right? (not to mention the tolerance of the components even in a modern amp) One amp all set to 5 will sound different than another amp set to 5 but nobody looses sleep over this. 

Experiment and twist the shit out of those amp tone, resonance, presence, and guitar volume and tone pots. You would be amazed just how much you can get out of your current rig for FREE!


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## paul-e-mann

James Freeman said:


> After some googling I find this quoted reply in blue the most relevant to the question.
> Thanks to george76 for keeping this information from Dr.Decibel.
> 
> I was trying to find a clear answer regarding the speaker tonal difference between 8 and 16 ohm, without the output transformer taps replies people usually give.


Another plus to using 16 ohm speakers say in a 2x12 which is what I do (8 ohm load), if for any reason a speaker blows or becomes disconnected I will have a 16 ohm load on the amp and no worries of damage to the amp.


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## SkyMonkey

Being a 112 cab and combo user, every 8 ohm speaker I own (2) is removed and languishing in a box somewhere.
16's are far more useful to me, and I probably can't tell the difference anyhow.

The only 8 ohm I have that intrigues me is a G12B-150 from a 1912 cab.


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## PentodeLicious

There are tonal differences.
For example the Vintage 30, 16 ohm version, is the fizzest speaker on the planet.
The 8 OHM is great and warm.
A 8 ohm greenback sounds different from the 16 OHM version.
Warmer with creamier top end.
I prefer the 16 OHM greenbacks though.
They sound more close to the original rock and roll sound we are used to.
I also find 16 OHM speakers tighter. good sometimes and not sometime else.

I really want to make a comparison video someday.
But also with checking the Thiele/Small differences.
Someday... when I'll have time.. which will be.... probably never


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## JBA

PentodeLicious said:


> There are tonal differences.
> For example the Vintage 30, 16 ohm version, is the fizzest speaker on the planet.
> The 8 OHM is great and warm.
> A 8 ohm greenback sounds different from the 16 OHM version.
> Warmer with creamier top end.
> I prefer the 16 OHM greenbacks though.
> They sound more close to the original rock and roll sound we are used to.
> I also find 16 OHM speakers tighter. good sometimes and not sometime else.
> 
> I really want to make a comparison video someday.
> But also with checking the Thiele/Small differences.
> Someday... when I'll have time.. which will be.... probably never


The thing to watch out for is the effect of which tap you are using. You might be very surprised at the tone difference you get when you compare two 8ohm v30’s in series off the 16 ohm tap vs two in parallel off the 4 ohm tap. So there are small speaker differences but there is a more noticeable frequency extension as you (impedance match) using higher impedance taps. You can still use both to your advantage if that floats your boat. It floats mine ;-)


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## PentodeLicious

JBA said:


> The thing to watch out for is the effect of which tap you are using. You might be very surprised at the tone difference you get when you compare two 8ohm v30’s in series off the 16 ohm tap vs two in parallel off the 4 ohm tap. So there are small speaker differences but there is a more noticeable frequency extension as you (impedance match) using higher impedance taps. You can still use both to your advantage if that floats your boat. It floats mine ;-)


Hmm That's interesting experiment. never tried that before.
I do have two 8 OHMS greenbacks and a 2x12.
I Wonder...


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## SkyMonkey

PentodeLicious said:


> Hmm That's interesting experiment. never tried that before.
> I do have two 8 OHMS greenbacks and a 2x12.
> I Wonder...


If 'Wonder' turns to 'Action', please record the results for a blind test we can try.


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## JBA

I’ll keep it as non technical as I can. The output transformer uses less of its output wire winds for 8 ohms than 16. Even less on 4 than 8. This is how it adjusts voltage for different loads. There is a loss in sound using the 4 ohm tap. If manufactures could they would use less copper in every transformer to save money. Why don’t they do this? They can’t. The 4 ohm tap on most non switch selectable transformers is basically a cheap transformer equivalent of the 16 ohm output of the same transformer. They could skip an 8 ohm output and use a switch for an equal 4 or 16 ohm settings. Looks like less options to the customer and cost them an extra switch so most don’t. For a hifi stereo this sucks, for guitar either scenario can work to your advantage.


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