Switchable JFET boost schematic

[TomAmp]

Hello

Was wondering if anyone has a good schematic for a switchable integrated JFET preamp/boost please? Footswitch even better

This preamp is promising but any other JFET circuits helpful
http://www.till.com/articles/GuitarPreamp/

Thanks

[pompeiisneaks]

If you look at the ODS amps, all of them have a fet in them, and it can be used as a clean boost. There is also a thread here: https://ampgarage.com/forum/viewtopic.php?t=31084 about using a footswitch with a relay into the existing ods fet module. You should be able to put two and two together, not sure if anyone's done a completely separate circuit of this, but it should work in most any input stage of a tube amp.

You can see the fet schematic and layout clearly as part of the dumble #124 found here: https://ampgarage.com/forum/viewtopic.php?f=5&t=5719

I've built this amp and the fet circuit can very easily be separated from the rest of the circuit.

~Phil

[TomAmp]

Thank you!

The dumble 124 schematic makes a lot of sense, just need to figure out the footswitch

[pompeiisneaks]

The footswitch itself is shown on the layout in the bottom right corner, as well, but basically all it needs to do is work inline with the 12V relay's power as a switch. Look at that section of the layout, There are lines connecting to the 5 pin connection and then the footswitch and the corresponding 5 pins.

Hope that makes sense? Yes it is a bit odd they put a schematic on the layout.

~Phil