Best 5E3 Cap Values?

[ncusack]

Hey Guys,

Just a quick question for everyone about the coupling and bypass caps in the 5E3. I've seen a few different layouts and mod forums around that suggest different values here and there. What I'd like to know is what values will provide the most even tones for both single coil and humbucker guitars.

one of the specific layout's I've seen is the one that used to be on schematic heaven that had values suggested by Bruce at mission amps and that had .022 on the bright .047 like everywhere else and 4.7u for the bypass caps. I figure if Bruce uses those its probably a good place to start but I'd like to hear some other opinions and reasoning behind it if possible.

Thanks in advance and I hope this doesn't stir up too much debate.

Cheers,

Neill

[fyl]

Use 22n for the first stage, 47n post-cathodyne, 4µ7 for Ck in the bright channel, 10µ for normal.

You may also consider using a larger cap in the TS, going from 500 pF to 1 nF or so gives a nicer tonal variation with some rigs; adding a 330K R between the 1M and V2's grid in order to reduce blocking disto when playing real hard; lifting the heaters in order to allow the use of crappy russki 12AX7s for V2; adding another filtering node and reduce noise/clean the disto.

Here's an example of a modded board to be used with a choke, voiced for vintage single coils and a well damped stiff speaker with a 1.5" VC - Ck are 22µ for V1 here:



And it's layo (early version, but still OK):

[ncusack]

Were those cap selections designed to work best with single coils or for both single and humbucker. Im looking to voice mine for both maybe have one channel for single and the other for humbucker if that's possible.

[fyl]

These values are fine for mixed use. You may lower the Ck values if you want more bite with dark-sounding humbuckers, something like 680n bright and 4µ7 normal can give excellent results. It's pretty easy to test various values, so feel free to do your own tests.

But this is only part of the equation: the speaker and the tubes used play a major role. A too bright voiced 5E3 with highish B+ and modern 6V6GTs thru a Celestion V30 will make your ears bleed...

[Bruce / Mission Amps]

With respect to the sound of a real 5E3 used with a good speaker, the only other simple mod I do, (that won't take the amp to some other sonic dimension not related to the vintage 5E3 sound), is to use a 680pF treble cap.
The mods previously mentioned by me are actually all I do to in order to retain more of the classic 5E3 tone but still be very usable with hotter and darker pickups.
Yes, of course there are lots of mods that can be done but eventually it will take you further and further away from the vintage tone of the amp, which is why I suppose you are building this one instead of some other amp... the classic vintage sound.
The use of HB guitars requires some other mods.... it's harder to get the amp to respond terrifically to to both types of pickups, HBs and single wind.
The ones you've mentioned will help quite a bit.