POWDOG wrote:Thanks guys. This really helps a lot. Short of building a different tone stack, I'm pretty sure this will get me into nirvana territory. I really appreciate all of your expertise.
If you do decide to rebuild the tone stack, give the James tone stack a try. The Rock/Jazz switch on the classic Dumble tone stack basically switches between a modified Fender stack and the James stack.
IMHO, the James is easiest to dial in, since there is less interaction between controls, and it works more like hifi tone controls.
You can also tweak the resistor between bass and treble controls to shift the base frequency around which they operate. Get the guy over with his guitar, turn up the treble and bass, and use a trimmer to find what frequency he likes. Then turn down the treble and bass and play with it that way also.
Unless you used stock specs for all the parts, the build wont sound the same as the original.
For example, one thing thats all important is the OT. If its got more iron than the original, it'll pass more bass, and you may want to then reduce the bass part of the bandwidth somewhere in the rest of the circuit to compensate. You might just want to experiment with higher roll-off point(s) in pre-amp stages (for example with smaller coupling caps, or smaller Ck). The V1 stage(s) would be where to try smaller Ck first - try going down to 1 or 2.2uF. For coupling caps try.01uF after V1 (instead of .02) and/or .047 after V2 (instead of .1), and/or same type of thing into the output tube stages. Will this work for your friend - depends. For tweaks, subtle changes often are best (i.e. one thing at a time)
Another possibility could be the NFB circuit. The amount of NFB can affect the bandwidth. Did you use a 56k NFB resistor? Has the OT got the same Pr:Sec impedance ratio as the 'original' 5E7?
I'm with Mr. Hankey on trying a smaller bypass cap on the input stage. That will slide a -6dB shelf up one octave every time you cut the value in half.
POWDOG wrote:Thanks guys. This really helps a lot. Short of building a different tone stack, I'm pretty sure this will get me into nirvana territory. I really appreciate all of your expertise.
If you do decide to rebuild the tone stack, give the James tone stack a try. The Rock/Jazz switch on the classic Dumble tone stack basically switches between a modified Fender stack and the James stack.
IMHO, the James is easiest to dial in, since there is less interaction between controls, and it works more like hifi tone controls.
You can also tweak the resistor between bass and treble controls to shift the base frequency around which they operate. Get the guy over with his guitar, turn up the treble and bass, and use a trimmer to find what frequency he likes. Then turn down the treble and bass and play with it that way also.
