|01-01-2014, 12:28 AM||#41|
Join Date: Dec 2013
man, my memory blows.
ok... voltages are way the **** off from what i thought, and are explaining why you were getting the sound you got and other issues...
i had a working amp i'd restored and flipped recently, the 704's little brother, the 700:
here's a schematic you won't find... i had to buy it, which means of course, i upped it for free to the web... make me pay? scuze me? bite me!!! now it's FREE...
<pant pant pant>
anyways... dig the voltages on q1 in particular... the second tranny is a driver for the transformer:
kinda like a tube amp, innit?
anyways... you heard my demo...
you've got my values, and what i built...
here's the voltages
if your transistors are biased up to 4.5v on the collectors, it's gonna sound like my initial did... like a cocked wah, real loud, no dynamics.
try getting them voltages down some, and see if it comes to life.
the rc network that's unmarked is wrong, too...
the output from the .1u cap off q1 collector should go to middle of the gain pot, but the rc network there is on the gain pot, not on the transistor.
the 1m/10p should be between b and c of q2 if you're only using the two transistors.
here's where i mean
this isn't right.... move it to here instead bro:
hollah back, let me know how ya make out my friend. we'll get this fingered out.
|01-01-2014, 12:54 AM||#42|
Jim'll fix it
Join Date: Aug 2005
Here are the voltages with the collectors adjusted to match yours.
Like I said, I just dumped the 1M/10p along with Q3 and that other stuff. The diagram above is the current circuit sans the unlabeled cap and resistor (which was just a series resistor for the gain pot and a treble bypass to make it sound better at lower gain settings).
|01-01-2014, 01:13 AM||#43|
Join Date: Dec 2013
those voltages look great.
btw, that was with the knobs set like this:
fuzz/gain 3:00 (3/4's)
tone/ volume 9:00 (1/4)
that gives me unity gain with plenty of dirt, and the guitar cleans up really nice as ya turn it down.
hey, if it sounds good, it is.....
if ya feel like adding the other stuff with the voltage adjusted, i think you'll be pleasantly surprised, brother... 12:12am...hmmm... happy new year!!
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