OK - here's the whole thing as I have build it.
It works – but please leave comments and recommend improvements.
I have used daughter boards because I have built the gate after the BOM - for the next version I'll come up with a one-board layout.
I could not get a TLE2426 so I used an Opamp as a rail splitter. All it does is produce 1/2Vcc – I guess a simple voltage divider would have also done the trick.
I changed the gate pot to B250K - you could even use a 100K or a C250K. With a 500K – only the range between 2 and 5 o clock is really usable otherwise the gate will cut off everything but hard strumming. I also omitted the 15K (R27) in Wlat's schematic. This way the gate pot is connected directly to ½ VCC and at 5 o clock the gate will let a note ring almost to its natural death. The rest of the pot range is only useful if you have any noisy pedals before the BOM.
The gate picks its trigger signal directly from the input which makes it a very fast opening, but also a very fast closing gate - very effective. I used a 3PDT switch for the Gate switch so I can cut the connection between D of Q7 and the Vol pot, use one pole for switching the gate LED and use the third pole for cutting off the input for the gate circuit. This way, when the gate is off, the signal runs only through the BOM.
Despite the three boards, the boards are pretty compact so everything fits in a size B enclosure. Pay attention to the cuts under some of the resistors and ICs.
R8 and R9 share a hole (black ring).
I could not find a proper symbol for the VTL in the program so I used an IC symbol – Pins 1 and 2 on the left are the LED Pins and the pins on the right are the Resistor pins.
R38 is now 1M - I have experimented a little and this value seems to keep the gate open the longest.
You can experiment with C19 – it affects the way the gate closes. The lower the values the more stutter you get.
You can replace the R34 trimmer with a 1K - it does not make much difference anyway. Actually I am not sure why there is a trim pot in the schematic.
The orange, red and black track markings on the boards are for orientation purposes only. Black is ground, red is Vcc and orange is Vr (1/2Vcc).
I usually draw these on my board with a felt pen - makes building easier.
I left out the LED and switch wiring - you should be able to figure this out by yourself.
Another question:
Does anyone else experience problems with the Mid control. It seems not to do much at all and it seems to cut the mids when turned fully clockwise.
This is almost a standard Marshall tonestack - only R22 and C8 are different.
I put Pin 3 of the Mid pot against ground and Pin 1 goes to Pin 1 on the Bass pot - this is correct, isn't it?