eliminating the thin sound of the JCM 900(4100) and my love for Channel B

[gtr1963]

Wanted to drop a line on the forum about a journey with my JCM 900. I have the 4100 head. Bought it new in late 90s. I go into a Park 4x12(made by Marshall) cab with Celestion G12-30s. Loved the sound when I bought it new in the 90s. Over the years, my tastes for sound have changed somewhat(that's my problem..lol). In that time I bought a DSL 100 with Marshall 1960A cab. I absolutely LOVE the sound from that amp. Instead of using one as a backup, I opted to go in stereo. I have a boss gt6 that has a left and right out. I go out right to effects return of DSL and left I go straight in to 900(A channel). I don't use the effects loop cause I'm running a rack BBE 362 in the effects loop( big thanks to Adrian for this tip). Since I'm an 80s metal guy(Judas Priest, Maiden, Loudness, etc) lover, that's the sound I'm going for. The Boss GT6 has the MetalZone pedal inside it, but it doesn't have all the EQ settings that the Boss MT2 pedal has. So, sometime back I bought the MT-2 Waza pedal and run that as my distortion out of my Boss GT-6(using the Fender Twin preamp) setting from the Boss GT6 in conjunction.

I pan the the delay in stereo(GT-6) and this gives me an awesome sound. However over the years, I noticed my 900 didn't sound as good(by itself) as my DSL did(by itself). Together they crush, because I'm blending 2 different models of Marshalls, but being the guy like all of ya'll in the never ending quest for tone, I thought the 900 sounded a bit lacking (for lack of a better term). It didn't sound bad, I think my preference for the DSL made the 900 not sound as good(to me).

I've done extensive(and I mean extensive) time fine tuning the 900 with the knobs. This brought me close to what I wanted. On the recommendation of member cosmacosmy I got a Groove tubes 7025 12ax7 preamp tube for V1.(By the way, all my tubes, preamp and power tubes are working fine).

This 12ax7 in V1 brought me even closer to the desired tone out of my 900. Then I decided to switch the 900 to channel B and fine tune the knobs on the amp. This made all the difference in the world. It sounds awesome now on its own and when I couple it with my DSL 100, it crushes. It almost brings tears to my eyes.

I've read thousands of posts where people love channel b, hate channel b, no opinion. While I've used channel b on occasion in the past, It took a lot of fine tuning the knobs on the front to get the sound I wanted. I know Channel B on the 900 has some haters, but in the end, it's what sounds good to your ears.

But, the sound is in the ear of the beholder. What I love, someone else may not. I want to post a clip of each separate and then together for others to hear, however I don't want to use just my cell phone to record. i don't think the full dynamics would be heard. I'll probably mike each amp and record into my computer and post the clips for all to judge for themselves. I think that might sound the best for others to hear what I hear. I'll try to get around to doing that when I can find the time.

​

 

[Neptical]

IMO - the best tool for any amp is an EQ ( MXR 10 Band) in the loop, especially a Marshall. Put that in tandem with an SD-1 up front and you have tones that will keep up with the best of them.

It's still surprisingly the cheapest, most effective and underrated piece of gear yet.

I've had the JCM 900 DR sounding SUPERB. It was borrowed, but I used it a bit just for shows. Right now I own a JCM 900 SL-X 2500. I use the same tools to put that amp right where I want it. No problem plugging in to that head even over my ole Dual Rectifier Rev G that sits right next to it - and that amp is magnificent.

 

[gtr1963]

IMO - the best tool for any amp is an EQ ( MXR 10 Band) in the loop, especially a Marshall. Put that in tandem with an SD-1 up front and you have tones that will keep up with the best of them.

It's still surprisingly the cheapest, most effective and underrated piece of gear still.

I've had the JCM 900 DR sounding SUPERB. It was borrowed, but I used it a bit just for shows. Right now I own a JCM 900 SL-X 2500. I use the same tools to put that amp right where I want it. No problem plugging in to that head even over my ole Dual Rectifier Rev G that sits right next to it - and that amp is magnificent.

Great!!. I'm sure it sounds awesome!! I may get me an SD-1 and EQ and try that out. Right now I got the BBE 362 in the loop(instead of EQ) and a Boss MT-2 instead of SD-1, but I'd love trying the SD-1, MXR eq in place of the MT-2 and BBE and see how that sounds..

 

[Neptical]

@gtr1963 Do it! You'll have to post back and let me know what you think. Tried and true tools right there, though there is not any one answer for everyone.

 

[cozmacozmy]

That's awesome that GT-7025 helped out so well! I was worried that my recommendation wouldn't meet what you were looking for. I'm gad to hear it is working so much better for you now!

As far as any other recommendation I'm afraid I can't help you there. I'm just a bedroom player myself and don't gig with mine. I do on occasion jam with my buddy who put me onto that GT-7025 and another friend with his full drum kit. But that's about it. But all 3 of us haven't gotten together yet since I got my GT-7025.

My favorite pedal right now to use on my 900DR is the JOYO clone of the MXR OCD pedal, the "Ultimate Drive". I got it as a gift and it sounds just like the demos I hear on YouTube of the OCD pedal. I do have a 7 band EQ as well I run I'm the effects loop. But I'm still dialing that in as that is fairly new to me too.

When I replaced my V1 with that tube it made the hair on my arm stand up! It was that big of a change! For anyone reading this and wanting to make their 900 sound better. Try and get yourself one of those preamp tubes!

 

[Filipe Soares]

adding to the SD1+EQ recipe: CRANK IT TO 11!

Almost all marshalls that I have or had sounded like shit in low volumes, but when cranked they are amazing. Attenuators are a marshall owner best friends.

 

[mmrizio]

Wanted to drop a line on the forum about a journey with my JCM 900. I have the 4100 head. Bought it new in late 90s. I go into a Park 4x12(made by Marshall) cab with Celestion G12-30s. Loved the sound when I bought it new in the 90s. Over the years, my tastes for sound have changed somewhat(that's my problem..lol). In that time I bought a DSL 100 with Marshall 1960A cab. I absolutely LOVE the sound from that amp. Instead of using one as a backup, I opted to go in stereo. I have a boss gt6 that has a left and right out. I go out right to effects return of DSL and left I go straight in to 900(A channel). I don't use the effects loop cause I'm running a rack BBE 362 in the effects loop( big thanks to Adrian for this tip). Since I'm an 80s metal guy(Judas Priest, Maiden, Loudness, etc) lover, that's the sound I'm going for. The Boss GT6 has the MetalZone pedal inside it, but it doesn't have all the EQ settings that the Boss MT2 pedal has. So, sometime back I bought the MT-2 Waza pedal and run that as my distortion out of my Boss GT-6(using the Fender Twin preamp) setting from the Boss GT6 in conjunction.

First of all: I am happy that you are happy with your sound. My response is more about my own curiosity than anything else. Feel free to ignore. But....

If I read correctly, you were happy with your DSL, but you are now bypassing the preamp in full? And you are only using the JCM900 preamp because you have the BBE in the loop? Can't you just bypass the preamp of the JCM900 as well by connecting the output from the GT6 to the input of the BBE?
Anyway: I am curious how you use the Metal Zone into the JCM900 preamp in channel B. You must be using really low gain (or how is it called on the JCM900 HGDR?) on both devices?

 

[gtr1963]

If I read correctly, you were happy with your DSL, but you are now bypassing the preamp in full? And you are only using the JCM900 preamp because you have the BBE in the loop? Can't you just bypass the preamp of the JCM900 as well by connecting the output from the GT6 to the input of the BBE?
Anyway: I am curious how you use the Metal Zone into the JCM900 preamp in channel B. You must be using really low gain (or how is it called on the JCM900 HGDR?) on both devices?

I have the 900 DR on the left and the DSL on the right. The boss gt6 has the ability to use external effects. The GT6 preset I made uses a Fender Twin Reverb for preamp and the Boss Metal Zone for distortion. I set the distortion to external and run the Metal Zone through the external effects jacks on back of GT6. So, I'm effectively still using the Boss Metal Zone as my distortion, only not the onboard Metal Zone preset the GT6 has, I'm using the pedal version Metal Zone(has more control parameters than the preset in GT6).

The left out from GT6, I go straight into the front of my 900. I have a rack BBE 362 Sonic Maximizer that I am running through the effects loop of the 900. The right out, I go straight into the effects return of the DSL, thus bypassing the preamp of the DSL. The DSL with the Metal
zone distortion and Fender Twin Preamp give it an ultra creamy distortion that I just love. Perfect 80s metal tone(to me). With the 900 since I'm going straight into the front, I can use channel A or B. I've used A for years, but Channel B sounds a bit better to my ears. Still a bit harsh, but not as bad. My settings on the 900 channel B preamp are turned down to about 3, so I'm not using a lot if any preamp from the 900. To my ears, it gets more harsh the more I turn the preamp up. I boost the volume on the 900 to compensate and equal out the sound to match the DSL's volume(going through the DSL effects return, the front knobs for volume, etc, don't function), so while I can't control the volume of the DSL amp, I can the 900, so I set the 900 to match the volume of the DSL and use the volume pedal of the GT6 to boost, lower volume.

A lot of trial and error to get to this setup, but it sounds good to me now and would sound killer in a live situation, especially using the stereo pan delay of the Boss GT6. I do wonder if I had another DSL instead of the 900 if it still would sound as thick as they would be the same amp. While the DSL and 900 do metal great, they are different flavors so the sound is a bit different from each, but blended together with stereo delay, it melts the face.

 

[cozmacozmy]

I'm wondering if the the difference from the 900 and DSL compliment each other? If you had 2 DSL it might not.

 

[gtr1963]

I'm wondering if the the difference from the 900 and DSL compliment each other? If you had 2 DSL it might not.

I'm almost in agreement with you on this. I think blending of 2 different models of the same make of amp does wonders, but I do wonder if 2 of the same make and model would give it the depth, layering.

 

[cozmacozmy]

Exactly!