Galileo low gain

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Galileo low gain

Benagro
Being an old Brian May fan, I loved the idea of the Galileo.
I was so happy when I found it here, I build it and, after a little debugging, it works quite well in terms of tone and colour. Nevertheless it is a bit far from the demo of the original in term of volume and particularly in term of gain.
I solved the volume issue changing the resistor near Q3 with a 47K I had available and with a 18V supply, but the gain is still low.
With my Red Special copy I can only have a clean sound from the CB30 section, while inserting the Naga give some crunch, but far from the Brian May saturation. Not to speak about my strat, that give me just mild crunch with everithing cranked up.
In this situation the Gain and Volume pots are useless, unless you want to go under unity.
Has anybody experienced/solved similar issue? Do you think it might have something to deal with JFET matching?
I also checked the schematics here:
http://freestompboxes.org/download/file.php?id=19604&mode=view
and I found a couple of differences.
First, the 47K resistor that goes to Gain 1 is described with the same value, but it is written that it could be increased. Do you think this could increase or decrease the gain? I will try it btw.
Second, the 470 cap near Q4, is connected, in the vero version I found here, between Drain and Source of Q4 itself, while in the other schematic is connected from Drain to Gain 3. Do you think this coud make any difference?
I'm too much of a noob in electronics to understand what does this can actually mean, but I'm confident the experts in this site will be able to explain.
Eventually I will try both mods and post the risults, if someone can confirm I won't fry anithing in doing this.
Thanks in advance to anyone that could help me, I REALLY would like to fix this.
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Re: Galileo low gain

induction
Benagro wrote
Do you think it might have something to deal with JFET matching?
I don't think matched jfets are necessary for this circuit.

First, the 47K resistor that goes to Gain 1 is described with the same value, but it is written that it could be increased. Do you think this could increase or decrease the gain?
As it says on the schematic, that resistor controls the minimum gain setting. With the gain knob dimed, it has no effect.

Second, the 470 cap near Q4, is connected, in the vero version I found here, between Drain and Source of Q4 itself, while in the other schematic is connected from Drain to Gain 3. Do you think this coud make any difference?
There are two 470p caps in the circuit. You're looking at the wrong one.

Low gain and volume sounds like a build problem. Post pictures and voltages.