Got this working ok, but there's one thing bothering me. When the switch is set to vintage the depth pot works in reverse. Modern, it's as expected. Weird!!
I read this comment and immediately went "that CAN"T be right!" but looking at the schematic, one of the mode switch selections is connected to leg three of the depth pot, and the other one is connected to leg one of the depth pot... which seems like it might make the switch function just like that. I guess the only way to verify would be try to find a demo of the original. To the youtube!!!
I actually love when I screw something up, figure it out, then correct it. Building something perfect the first time is great and all, but I am so much more proud of a build when I have to go through this process. Seriously, nice work, Ben!
Another entry for verified. This thing is wild. Volume on a guitar make big changes in sound structure as there is no gain control at all.
Also I have tried all my soviet germanium transistors (10+ like GT402, 308, 318, 20, 25, 416 and so on with different letters) in many combinations on it and has stopped on MP42B (cyrillic "Б") for Q1 and 1T308B (cyrillic "Б", 1T = GT) for Q2 as best open sounding ones, kind a same like in demos if not better.
Last observation, with two low gain trannies it became really nice warm sounding booster with a bit of a breakup.
Got this working ok, but there's one thing bothering me. When the switch is set to vintage the depth pot works in reverse. Modern, it's as expected. Weird!!
ReplyDeleteI read this comment and immediately went "that CAN"T be right!" but looking at the schematic, one of the mode switch selections is connected to leg three of the depth pot, and the other one is connected to leg one of the depth pot... which seems like it might make the switch function just like that. I guess the only way to verify would be try to find a demo of the original. To the youtube!!!
DeleteIdiot alarm! I'd got the first 2.2nf cap one space too high. Works perfectly now.
DeleteI actually love when I screw something up, figure it out, then correct it. Building something perfect the first time is great and all, but I am so much more proud of a build when I have to go through this process. Seriously, nice work, Ben!
DeleteThanks Chris. Very well said. I should remind myself of that more often instead of throwing my toys out the pram! :-)
DeleteThanks guys for verifying!
DeleteThat’s weird, it’s only function is to swap the different capacitor pairs, how does that happen? Unless there’s an error in one of the connections?
ReplyDeleteAnother entry for verified. This thing is wild. Volume on a guitar make big changes in sound structure as there is no gain control at all.
ReplyDeleteAlso I have tried all my soviet germanium transistors (10+ like GT402, 308, 318, 20, 25, 416 and so on with different letters) in many combinations on it and has stopped on MP42B (cyrillic "Б") for Q1 and 1T308B (cyrillic "Б", 1T = GT) for Q2 as best open sounding ones, kind a same like in demos if not better.
Last observation, with two low gain trannies it became really nice warm sounding booster with a bit of a breakup.