Peeps, a little help from the veterans:
Trying to build a Keeley Katana, and saw from the only schematic on the internet (the one hand-drawn on a yellow sheet of pad paper) that, judging by the JFETs, this is some sort of Fetzer valve design. However, I tested my 2N5458s and found out that instead of 680 ohms for the source resistors, 330 ohms should produce better results in theory, whether the transistors are run at 9 or 18 volts (the Katana of course has a built-in voltage doubler circuit).
Unless Keeley did choose 680 ohm source resistors intentionally, I get this nagging feeling that he doubled the value mistakenly because he intended to run the pedal at double the voltage, not knowing that the value only changes for the drain resistance as the input voltage increases. Am I onto something here, or did Keeley have a design different from the fetzer valve type circuit that required different value parts? Or maybe Keeley's JFETs measure an average rating for which 680 ohms is the average resistance useable? Thanks in advance for replies.
