Amp tinkerers... Discovered the angriest-sounding capacitor

[FourT6and2]

That's exactly why I don't like his amps. Too dark. Too round. Too loose. Too polite and smooth. Everybody's got their preference of course. Mine? Angry, mean, growly, snarly. That doesn't mean fizzy or harsh or grating. But all the Friedman amps I've played have been on the opposite end of the spectrum. So far, all the Cameron amps I've heard are closer to what I like. And the Chupacabra comes the closest out of anything I've owned. This amp I'm building now will be heavily based on that, but with a number of tweaks.

Don't mean to bomb the thread about capacitors,
just wanted to say thank you FourT6and2 for your posts about amps and your tone quest in general.
It has really helped me in finding a better sound, since it seems we share the same preference in how an amp should sound.
Your clips od Chupacabra and Diezel sound great, don't know how many times I have listened to them.
Eventually I modded a 5w amp to yeti preamp specs and so far it is the best preamp scheme I found on a hot rodded Marshall.

Could you maybe share your tweaks of Chupa, if you don't mind me asking.

Thanks again.
and sorry for this out of topic post.

Hey there thanks for the kind words.

I will create a build thread on the amp once I start. You'll be able to follow along with the build and see what I do. That won't be for another month though (I'll be out of town for work for a bit).

 

[marcus262]

Will follow your build.
Thanks.

 

[Rdodson]

Can't wait for the build thread - that last one was Gil Yaron epic!

 

[scottosan]

It's just a matter of preference and position. When used for coupling they basically allow how much bottom end is allowed through. The lower the value, the less low end allowed through. My experience with sozos is that they let less low end through to me ears for a given value which equates to a clearer more cutting tone. Take WIMA for example is a more Nuetral and more consistent cap @ 5% tolerance on the ones I use. To me they sound more balance which to some could be less aggressive or not as clear, but ultimately it's a slight adjustment in the controls. I especially hear the difference using these for cleans and in high frequency positions as IMHO have the smoothest highs and you can get them in low values that are only available in ceramic or mica from other vendors

 

[psychodave]

Yes big improvement with the Synergies. I really want to play a Bogner 20th with the new Synergy nexgens because my only complaint with that amp was smearing in the gain. I ended up backing off the gain and increasing the volume to compensate but then you are losing part of what makes that amp cool, and it is a different animal. I understand that the new caps have really fixed that issue. I'll tell you the BE100 has zero of that going on, the gain structure is pristine without that gritty, fizzy, lispy thing. I have a clip of my old 20th in the Red channel where you can hear what I'm describing.

Yes the Synergy/SoZo nexgens are very clear, they would be a massive improvement over the Wima's (i think that's what in there) that Bogner used.

Yes the BE100 is great, I've studied that circuit extensively, and modded my metro superlead 100 to the BE. You don't get any fizzy's with the BE because Dave did a great job strategically placing 500pf plate bypass caps in the right spots, and limiting bandwidth early on in the preamp. Really the amp sounds so refined because its like having a shelving EQ built in.

I hated those 500pf caps in the Friedman Jet City 20 I had. I went through the amp with Mark Cameron and removed all of them...then did a bunch of other mods and the amp sounds insane.

 

[IndyWS6]

Yes big improvement with the Synergies. I really want to play a Bogner 20th with the new Synergy nexgens because my only complaint with that amp was smearing in the gain. I ended up backing off the gain and increasing the volume to compensate but then you are losing part of what makes that amp cool, and it is a different animal. I understand that the new caps have really fixed that issue. I'll tell you the BE100 has zero of that going on, the gain structure is pristine without that gritty, fizzy, lispy thing. I have a clip of my old 20th in the Red channel where you can hear what I'm describing.

Yes the Synergy/SoZo nexgens are very clear, they would be a massive improvement over the Wima's (i think that's what in there) that Bogner used.

Yes the BE100 is great, I've studied that circuit extensively, and modded my metro superlead 100 to the BE. You don't get any fizzy's with the BE because Dave did a great job strategically placing 500pf plate bypass caps in the right spots, and limiting bandwidth early on in the preamp. Really the amp sounds so refined because its like having a shelving EQ built in.

I hated those 500pf caps in the Friedman Jet City 20 I had. I went through the amp with Mark Cameron and removed all of them...then did a bunch of other mods and the amp sounds insane.

I thought you sold that one...

 

[nico22]

Dave, did you and mark keep the regular master of the jet city or converted it into Jose one?

 

[psychodave]

Dave, did you and mark keep the regular master of the jet city or converted it into Jose one?

It had a Jose master in it already, but changed it around to sound better. I also added a 3-way switch to have different clipping options. Honestly, the amp is killer. Sounds massive.

 

[Braciola]

I don't care SoZo at all....... too dark.
I was talking to Greg Germino....... He stopped using them in his amps a while ago and commented that the he disliked the newer SoZos even more.

 

[FourT6and2]

Well can't say I've done an A/B test or anything, but those MPW caps seem to do the trick in my latest build. I'm using them in all the coupling positions and Vishay/ERO MKT1813 in the bypass positions since I couldn't find any MPWs physically small enough to fit at 0.68uF/630v. They make 150/250v ones but nobody has them in stock. The ERO are the right size, so I used 'em. I guess I could have use the Mallory 150s. I just forgot I had 'em haha.

Also, if you can find them those Philips KP-series blue polypropylene film caps are great in the pF range for bright caps and tone stack and mixer bypass instead of mica or ceramic. They have a nice throaty grunt.

 

[PatF]

Cool.
What about Solen for cathode bypass? Haven't compared, but I've used them a few times now with good results.

 

[scottosan]

Cool.
What about Solen for cathode bypass? Haven't compared, but I've used them a few times now with good results.

I would invest in coupling caps more that bypass caps.. People overlook the tolerance. I never go over a 5% tolerance cap except for filtering

 

[idnotbe]

That's exactly why I don't like his amps. Too dark. Too round. Too loose. Too polite and smooth. Everybody's got their preference of course. Mine? Angry, mean, growly, snarly. That doesn't mean fizzy or harsh or grating. But all the Friedman amps I've played have been on the opposite end of the spectrum. So far, all the Cameron amps I've heard are closer to what I like. And the Chupacabra comes the closest out of anything I've owned. This amp I'm building now will be heavily based on that, but with a number of tweaks.

just curious...
what can be the high-level strategy to change BE-100 into more aggressive, raw one?

i like the massive but tight low end of BE-100.
but want more aggressive / angry / stiffer / raw.

 

[sjk]

That's exactly why I don't like his amps. Too dark. Too round. Too loose. Too polite and smooth. Everybody's got their preference of course. Mine? Angry, mean, growly, snarly. That doesn't mean fizzy or harsh or grating. But all the Friedman amps I've played have been on the opposite end of the spectrum. So far, all the Cameron amps I've heard are closer to what I like. And the Chupacabra comes the closest out of anything I've owned. This amp I'm building now will be heavily based on that, but with a number of tweaks.

just curious...
what can be the high-level strategy to change BE-100 into more aggressive, raw one?

i like the massive but tight low end of BE-100.
but want more aggressive / angry / stiffer / raw.

Just buy a wizard, that's what I did a year and a half ago and no mods or changes needed lol.

 

[idnotbe]

Just buy a wizard, that's what I did a year and a half ago and no mods or changes needed lol.

wizard sound is not compelling to me, though i hear it through youtube.

 

[FourT6and2]

Just buy a wizard, that's what I did a year and a half ago and no mods or changes needed lol.

wizard sound is not compelling to me, though i hear it through youtube.

Yeah I agree. I haven't heard any Wizard clips that sound good to me. They're all kind of harsh and fizzy. But yeah, the circuit itself isn't anything special. Same old same old Marshall thing. Build quality is kind of lackluster fora $4K amp too.

As far as changing a BE100 to be more aggressive. I don't know off-hand. I would need to see the schematic. I have one. But apparently it's incorrect. Maybe Scott might know. He's more familiar with that amp.

 

[CrazyNutz]

just curious...
what can be the high-level strategy to change BE-100 into more aggressive, raw one?

i like the massive but tight low end of BE-100.
but want more aggressive / angry / stiffer / raw.

Change the screen filters from 16uf to 47-50uf
Change the preamp filters from 22uf to 47-50uf
Connect the NFB to 4 ohm tap.

Going further:
Remove or lower the 500pf cap across the plate resistor of the CF stage.
Reduce the fizzy cap on the PI from 100pf to 47pf
Remove or lower the the 500pf cap on the first gain stage plate (in case HBE remove or lower on fist two gain stages).

EDIT: you may also want to do 1N4007 diodes in the rectifier, the plate voltage will go up 20ish volts. The UF4007's sound smoother, and more brown.

 

[FourT6and2]

just curious...
what can be the high-level strategy to change BE-100 into more aggressive, raw one?

i like the massive but tight low end of BE-100.
but want more aggressive / angry / stiffer / raw.

Change the screen filters from 16uf to 47-50uf
Change the preamp filters from 22uf to 47-50uf
Connect the NFB to 4 ohm tap.

Going further:
Remove or lower the 500pf cap across the plate resistor of the CF stage.
Reduce the fizzy cap on the PI from 100pf to 47pf
Remove or lower the the 500pf cap on the first gain stage plate (in case HBE remove or lower on fist two gain stages).

Does the PI fizz cap do much going from 100pF to 47? I mean combined with everything else, yeah. But how about just by itself? I'd have to do the math, but I think either way, the frequencies are well above the human range of hearing, let alone with a guitar amp speaker is able to reproduce.

 

[CrazyNutz]

Does the PI fizz cap do much going from 100pF to 47? I mean combined with everything else, yeah. But how about just by itself? I'd have to do the math, but I think either way, the frequencies are well above the human range of hearing, let alone with a guitar amp speaker is able to reproduce.

I can feel the difference more than I can hear it (I can hear it too), feels more open, less choked. If that's what you are going for. I usually go for 100pf on just about anything because I like the slight smoothing.

It's not a massive thing, but in combination with the other tweaks it adds up.

BTW I've done the math on many things like this, same with the grid stoppers on power tubes where the math says these can go > 20k ohms before it makes any difference. We'll I gave up on the math, because I can tell the difference between 1.5k ohms, and 5.7k ohms.

 

[FourT6and2]

Does the PI fizz cap do much going from 100pF to 47? I mean combined with everything else, yeah. But how about just by itself? I'd have to do the math, but I think either way, the frequencies are well above the human range of hearing, let alone with a guitar amp speaker is able to reproduce.

I can feel the difference more than I can hear it (I can hear it too), feels more open, less choked. If that's what you are going for. I usually go for 100pf on just about anything because I like the slight smoothing.

It's not a massive thing, but in combination with the other tweaks it adds up.

BTW I've done the math on many things like this, same with the grid stoppers on power tubes where the math says these can go > 20k ohms before it makes any difference. We'll I gave up on the math, because I can tell the difference between 1.5k ohms, and 5.7k ohms.

Yeah I know what you mean. Like people say there's no audible difference between 470pF and 500pF tone stack treble cap. But to me it's a fairly noticeable difference. My current builds all have 100pF fizz cap. I was going to try 47pF in one of them but I just didn't bother. I might parallel another 47pF in one of my amps that has 47pF there to see if I can hear a difference.