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just some raw data/impressions/things noticed...
-grounding scheme looked a bit weird intuitively (from a tube amp perspective) so changed it a little bit. (Specifically, ground point at the input as a star goes to output jack, also to pots, also towards ground trace at input. Using isolated switching jack at input--the sort where it's basically a DPDT--and switching batt negative in to ground circuit here. A ground wire goes from the sw. terminal to 470 ohm ground on PCB. Was kind of guessing but seems to work okay.)
-built positive supply version with 2N5087 for Q1, 2N4401 for Q2&3 (had them already)
-tried flipping orientation of Q1 (unit works both ways with a slight difference in sound), +18V supply, different control settings, gtr. vol. tone settings but so far the most significant change to make it sound like the sound clips from "boutique" versions (and Hendrix recordings--how could I forget!!! doH!) was using matched diodes (found info in ampage archives to match them using diode function on DVM). Noticeably better effect after installing the matched diodes. Stronger effect on neck pickup but okay on bridge PU as well. Rolling down the gtr.'s tone control makes effect work better (maybe necessary). (Got the idea that maybe a tone control to roll off highs on the octavia itself might be better.) Sort of seems a softer touch can bring out the octave effect more. Fuzz was perhaps better at 9V(need to try again to see). Used 1kA for gain (couldn't find a lin taper in my parts stash--perhaps a better adjustment range can be gotten with linear?).
-using apparently the older version PCB. My advice if you have misaligned indents for the centers is to repunch them. I went ahead and drilled a misaligned hole and had to cut a bit of the PCB mount. No big deal though.
-grounding scheme looked a bit weird intuitively (from a tube amp perspective) so changed it a little bit. (Specifically, ground point at the input as a star goes to output jack, also to pots, also towards ground trace at input. Using isolated switching jack at input--the sort where it's basically a DPDT--and switching batt negative in to ground circuit here. A ground wire goes from the sw. terminal to 470 ohm ground on PCB. Was kind of guessing but seems to work okay.)
-built positive supply version with 2N5087 for Q1, 2N4401 for Q2&3 (had them already)
-tried flipping orientation of Q1 (unit works both ways with a slight difference in sound), +18V supply, different control settings, gtr. vol. tone settings but so far the most significant change to make it sound like the sound clips from "boutique" versions (and Hendrix recordings--how could I forget!!! doH!) was using matched diodes (found info in ampage archives to match them using diode function on DVM). Noticeably better effect after installing the matched diodes. Stronger effect on neck pickup but okay on bridge PU as well. Rolling down the gtr.'s tone control makes effect work better (maybe necessary). (Got the idea that maybe a tone control to roll off highs on the octavia itself might be better.) Sort of seems a softer touch can bring out the octave effect more. Fuzz was perhaps better at 9V(need to try again to see). Used 1kA for gain (couldn't find a lin taper in my parts stash--perhaps a better adjustment range can be gotten with linear?).
-using apparently the older version PCB. My advice if you have misaligned indents for the centers is to repunch them. I went ahead and drilled a misaligned hole and had to cut a bit of the PCB mount. No big deal though.
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