cliffc8488":17fmxdm1 said:
And what's with the loop design? Yikes... talk about a hot send level. And before the tone stack?
Yeah, the loop is a pain. I really have no idea why Mike thought it's a good idea to send the unshaped sound out to Fx.
The problem is, if you fix the issues like clean/crunch channel bleeding into lead out of phase, loop voltage levels, making the tone stack more responsive, it loses it's magic.
From a technical point of view I would say the whole design is in early prototype phase. But sometimes it just turns out good and the SLO is very good.
I would consider these on the FLO model
From
http://www.schematicheaven.com/newamps/soldano_slo100.pdf
Mod 1. To lose some bass I changed the coupling cap of V2a from 22n to 2n2. I also changed the
coupling cap of V1a to a smaller value, you might not want to do this for it also affects the
clean/ crunch channel.
Mod 3. You could also change the decoupling cap of V2a from 1uF to .47 How much bass you need
too lose depends on your situation (guitar, playing style, cabs, etc).
Mod 4. To make the clipping of V2 sound a bit less radical change the cathode resistor of V2b to
10K.
Mod 5. To get a brown sound out of the lead channel I lowered the voltages for V2 to about 200V.
Mod 6. Removing the 2n2 cap that's placed across the 470k resistor (after V1's coupling cap) will
reduce mid / high frequency response.
Mod 7. Lowering the value of the 470k resistor placed after the coupling cap of V2a will increase
gain. I wouldn't do this but is possible.
Mod 8. Soldano already used the large 470k resistor going from the gain pot to the grid of V2a,
this resistor rolls of highs (in combination with the miller capacitance. You could use a similar
resistor in other stages to get the same effect.
Mod 9. Note that the clean/crunch channel is also in when you use the lead channel. The lead and
clean channel are not in-phase with each other. Though the level of the clean channel is much
lower than the lead channel's level the effect is still audible. I used an extra optocoupler to
switch the clean channel out of the signal path when the lead channel is selected.
Mod 10. This isn't a mod I used but it might be useful it can also be used in other amps (like
most of the mods above) by placing a small cap (let's say 470p) across the 470k resistors that
are in series with the coupling cap you will get more highs / edge in your distorted sound.
Pick me up on your way 
