How To Brighten Amp - Bright Cap Or Tone Cap?

paul-e-mann

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I just built a 5E3 and it sounds great but with humbuckers I wish I could dial the tone up a little brighter. Looking at my layout I have a .0047uF tone cap and a 500pF bright cap, I'm not sure which would be the best to make my tone knob go a little further in brightness and what values to use. Suggestions appreciated thanks!

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Vesperado

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Have you tried a smaller value cap on your guitar tone pot? Otherwise, tone cap/slope resistor: there's DTSC online for that. Ideally you want more highs, so lowering your slope resistor is a good place to start, then figure your desireable corner freq (by ear or target figure) and adjust the cap value thence.
 

Chris-in-LA

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To me, Fender guitars sound better with those old tweed designs, especially Telecasters. Try your Gibsons on one of the lower inputs or turn the amp volume down a little, that might also help.
 

XTRXTR

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Back off the guitar volume a bit and raise the amp volume. Then you have more room for a solo to really sing out loud even though its tone would be back to less bright. Increase your strings to 11s.
 

Pete Farrington

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5E3 don’t have a tone stack as such, so no slope resistor.
To make the tone control more trebly at full CW, increase the value of the 500pF cap.
But if the bright channel volume control is set high, it won’t make much if any difference.
Earlier guitar amp designs aren’t very bright. Hence Rangemasters etc were a thing.

Try your Gibsons on one of the lower inputs

My thinking is that using the low inputs reduces the amp’s input impedance from 1M to 136k. That will cause a noticeable degree of loading on the guitar, reducing the resonant peak of the pickups, similar to turning the instrument’s tone control down some. Hence that seems unlikely to achieve a brighter response from the rig.

Edit see Fig. 14. Response of a Fender Stratocaster pickup with 470 pF load capacitance and different Ohmic loads http://www.buildyourguitar.com/resources/lemme/secrets14.gif
From http://www.buildyourguitar.com/resources/lemme/index.htm
 
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Gene Ballzz

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@paul-e-mann ,
With the 5E3 circuit, there is not much you can do to "dial the tone up a little brighter" but instead cut some of the bottom end to allow the high end to dominate a little bit more. There are multiple ways to do this, coupling caps in either of a couple/few places, negative feedback, etc, with varying results from each. A great resource for "everything 5E3" in terms of mods and understanding the magic capabilities of the design can be found here:


and at the TDPRI Telecaster forum! I've not done any of them, as I love my 5E3 as it is, bone stock! Be careful to not get too lost down the rabbit hole of mods, as its easy to ruin an already fairly good amp. Try one mod at a time, to achieve your specific goal, instead of a complete redo of multiple mods! Its really a shame to try to make this design into something its not! A small mod can do a lot on these simple circuits.

All that being said, I've noticed throughout multiple forums and 5E3 users, that most feel the Weber output transformers leave the amp kinda dull and lifeless in the high end. Too bad ClassicTone isn't still around, but the MojoTone 5E3 OT is fairly well regarded and I know mine sounds great!

Simply Tweedin'
Gene
 

Chris-in-LA

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Those .1 caps do make the 5e3 a bit flubby sounding. Fender puts .022 caps at the phase inverter on their Edge signature model. I put the .022’s on v1 instead and that tightened up the bottom end considerably. But the amp really came alive when I put a Vintage 30 speaker in it.
 

paul-e-mann

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To me, Fender guitars sound better with those old tweed designs, especially Telecasters. Try your Gibsons on one of the lower inputs or turn the amp volume down a little, that might also help.
5E3 don’t have a tone stack as such, so no slope resistor.
To make the tone control more trebly at full CW, increase the value of the 500oF cap.
But if the bright channel volume control is set high, it won’t make much if any difference.
Earlier guitar amp designs aren’t very bright. Hence Rangemasters etc were a thing.

@paul-e-mann ,
With the 5E3 circuit, there is not much you can do to "dial the tone up a little brighter" but instead cut some of the bottom end to allow the high end to dominate a little bit more. There are multiple ways to do this, coupling caps in either of a couple/few places, negative feedback, etc, with varying results from each. A great resource for "everything 5E3" in terms of mods and understanding the magic capabilities of the design can be found here:


and at the TDPRI Telecaster forum! I've not done any of them, as I love my 5E3 as it is, bone stock! Be careful to not get too lost down the rabbit hole of mods, as its easy to ruin an already fairly good amp. Try one mod at a time, to achieve your specific goal, instead of a complete redo of multiple mods! Its really a shame to try to make this design into something its not! A small mod can do a lot on these simple circuits.

All that being said, I've noticed throughout multiple forums and 5E3 users, that most feel the Weber output transformers leave the amp kinda dull and lifeless in the high end. Too bad ClassicTone isn't still around, but the MojoTone 5E3 OT is fairly well regarded and I know mine sounds great!

Simply Tweedin'
Gene

Have you tried a smaller value cap on your guitar tone pot? Otherwise, tone cap/slope resistor: there's DTSC online for that. Ideally you want more highs, so lowering your slope resistor is a good place to start, then figure your desireable corner freq (by ear or target figure) and adjust the cap value thence.

My Strat sounds perfect with this amp but I mostly play Gibsons, I did put a pre pi master volume on the amp that works great, I only have the channel volume half way up, it really is the bottom end that I'm trying to tame I figured a bright cap increase would fix that. I'm currently using a Boss processor to fix the tone but I wanted this amp to be plug and play with minimal pedals.
 
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Chris-in-LA

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My Strat sounds perfect with this amp but I mostly play Gibsons, I did put a pre pi master volume on the amp that works great, I only have the channel volume half way up, it really is the bottom end that I'm trying to tame I figured a bright cap increase would fix that. I'm currently using a Boss processor to fix the tone but I wanted this amp to be plug and play with minimal pedals.
See post #8, change out some of the .1 caps, that removes a lot of bottom end.
 

paul-e-mann

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Those .1 caps do make the 5e3 a bit flubby sounding. Fender puts .022 caps at the phase inverter on their Edge signature model. I put the .022’s on v1 instead and that tightened up the bottom end considerably. But the amp really came alive when I put a Vintage 30 speaker in it.
Are you suggesting change out the pair of .1 caps only on V1?

I did see Robinette has an Edge mod, I'll take a look at that.
 
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paul-e-mann

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@paul-e-mann ,
With the 5E3 circuit, there is not much you can do to "dial the tone up a little brighter" but instead cut some of the bottom end to allow the high end to dominate a little bit more. There are multiple ways to do this, coupling caps in either of a couple/few places, negative feedback, etc, with varying results from each. A great resource for "everything 5E3" in terms of mods and understanding the magic capabilities of the design can be found here:


and at the TDPRI Telecaster forum! I've not done any of them, as I love my 5E3 as it is, bone stock! Be careful to not get too lost down the rabbit hole of mods, as its easy to ruin an already fairly good amp. Try one mod at a time, to achieve your specific goal, instead of a complete redo of multiple mods! Its really a shame to try to make this design into something its not! A small mod can do a lot on these simple circuits.

All that being said, I've noticed throughout multiple forums and 5E3 users, that most feel the Weber output transformers leave the amp kinda dull and lifeless in the high end. Too bad ClassicTone isn't still around, but the MojoTone 5E3 OT is fairly well regarded and I know mine sounds great!

Simply Tweedin'
Gene
Right now the amp is stock with only a master volume added, its a great sounding amp as is I dont want to stray too far from it. What specifically do you suggest to cut some of the bottom end?
 

paul-e-mann

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Those .1 caps do make the 5e3 a bit flubby sounding. Fender puts .022 caps at the phase inverter on their Edge signature model. I put the .022’s on v1 instead and that tightened up the bottom end considerably. But the amp really came alive when I put a Vintage 30 speaker in it.
Interesting, as you mentioned Edge replaced all the .1 caps with .022 on V2 but you replaced them on V1, what would be the tonal difference in each way? Or either way would get the job done? I'd rather do V1 so no risk of the bottom wires of the board falling out on V2.

LQ8g52y.png
 
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Chris-in-LA

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Interesting, as you mentioned Edge replaced all the .1 caps with .022 on V2 but you replaced them on V1, what would be the tonal difference in each way? Or either way would get the job done? I'd rather do V1 so no risk of the bottom wires of the board falling out on V2.

LQ8g52y.png
Not sure what the difference might be but changing the v1 caps sure decreased the mud. I’ve been tempted to try the Edge mod but the amp finally sounds so great I can’t be bothered at present. My amp started life as a Tube Depot amp that sounded so crappy I couldn’t understand why anyone would want to play a 5e3. It was gradually turned into the Mojotone version, completely stock with the exception of the v1 cap change.
 

thetragichero

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decreasing bass early in the circuit will do that. very important in high gain amps (think about the slo or jcm800, although both employ treble peakers to further decrease low frequency content)
 

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