I'm about 1/3 through building a fetzer/ruby from this schematic (top)
and i want to add a tonestack like this one(middle)
im planning on adding a warp control ala AMZ like this(botom) but i plan to use leds instead of the germanium's im wondering where i should put this in the circuit after the tonestack or before?
and i also plan to replace one of the j201 fets(the one after the tone stack) with a 2n3904 will i have to make any drastic mods to the circuit to accommodate this besides biasing the transistor differently?
(http://img508.imageshack.us/img508/8572/superruby1copyav4.jpg)
(http://diystompboxes.com/pedals/fender3knob.jpg)
(http://www.muzique.com/images/warp9.gif)
I'm certainly no expert, but I would first stick the warp control after the tonestack. Then, I'd try it in front of the tone control. Of course, if you look at http://www.muzique.com/lab/tclip.htm (http://www.muzique.com/lab/tclip.htm), you'll see idea for placing it inside the tone control.
Looks like it's a breadboard project. Make sure you give us feedback on your experiment, Eric.
anyone have any advice about the 2n3904 instead of the j201?
where are you planning to put the clipping diodes? After the first jfet or the second?
You can use any other type of gain stage including the transistor in question. You'll have to change the circuit to accomodate that type of transistor circuit but that shouldn't be that big of a deal on a breadboard. Also, on the 1m to ground before the 2nd jfet you might stick that on a pot to tweak it a bit in case you are getting alot of "flubbiness". I usually stick a voltage divider between each jfet stage and make sure I'm not driving them to hard. Some may like it, it's just a personal preference, I don't.
Also, you may have more tweakable results with a big muff style tonestack and tweak the values (see amzfx website for an article on this).
bw