Page 60 - Triwatt Custom Lead Amp Builder's Guide

Tone Tweaking

Below are some modifications you might try in order to change the tone and response of your
TRIWATT.

V1 Pin 8 - Townshend/Who CP103 1k5 + 64uF
V1 Pin 8 - Jimmy Page amp 2k2 + 100uF with additional parallel 1k5 resistor
V1 Pin 8 - SAP DR 103 2k2 + 100uF (no additional resistor)
V1 Pin 8 - Late '70s, Late '80s and OL/Lead 1k5 + 150uF

V2 Pin 3 - Townshend /Who CP103 2k2 + 47nF (47nF = .047uf)
V2 Pin 3 - Page/SAP DR103 1k5 + 47nF

If you want to mod your TRIWATT to any of these versions, solder the extra components onto
the existing turrets.

Normal channel gain can be reduced a little more by changing the cathode resistor on V1 Pin 8
from 1k5 to 2k2, like in early ‘70s models. Just another small tweak you may want to consider.

To get a bit more clean put a 5751 in the V3 position, with a 12AT7 in the PI V4 will provide
more clean on the MV control. Optionally remove the 47n bypass cap on V3 pin 8. Removing the
cap would reduce a fair bit of post-MV gain, as well as increase bass, but may not be to the liking
of those folks who would want a Triwatt for its earlier breakup compared to a DR.

More Tips for fine tuning your amp

Reprinted with permission from Aron from diystompboxes.com

These are very simplistic modifications you can do to your amp, let your ears be
your guide:

 Change coupling caps; changing to smaller values reduces bass, changing to larger values
adds more bass. Reducing the value of coupling caps can help eliminate "flabby" bass
syndrome.
 Change cathode bypass caps. Adding a cathode bypass cap to a stage that doesn't have one
will let the stage have more gain. Just like coupling caps, making the value larger adds bass -
generally 25uF allows almost all bass through, .68uF are used in some Marshalls for a more
midrange boost and 1uF and 5uF are used in some high end fusion type amps. Again,
smaller values can help reduce "flabby" bass.
 Change cathode resistors - larger values reduce gain, smaller values give more gain. A
"trick" is to connect a 5K+pot wired as a variable resistor instead of the standard cathode
resistor - now you can turn the pot and dial in the perfect tone. After dialing the sound,
remove the resistor and pot and measure it. Substitute the nearest standard value resistor in
place of the pot plus a resistor.

TrinityAmps TRIWATT Builders Guide Ver. 2.31.docx
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