I just finished building it with the right drive pot connection and it works correctly, also the transistors symbols (not the pinouts) are reversed for 2N3904, thank you for making the layout of the latest "correct" schematic, It's a good sounding overdrive
Sorry, had an error with the link for some reason. Reposting here my build and answering your question below: https://hgecontraptions.blogspot.com/2025/08/hge-contraptions-xotic-ac-booster-clone.html
You can omit the 100k output resistor to slightly lower the output impedance and get a bit more high-end clarity or let's say brightness, especially when driving long cables or low-impedance inputs. Also gives a little bit more level at the output, since we are basically removing a small series resistance, but it is less predictable, with different gear and also the potential for certain noise aspects like pops and whatnot can grow. Just a personal preference, while in tests.
I might put it back to adhere to the original idea, who knows :D I wanna change something else also so maybe will do that when I open it up again. I did test with and without, for kicks, and for my purpose it was a bit nicer without it.
Gotta be honest, I agree with you. I did the Xotic RC a long time ago for someone (also not impressed). I am also not impressed about the AC haha, but was just curious. I also did their Xotic EP Booster, but I did another version, as yet again their EP to me doesn't sound right with their stock bias, meh, but this is just my own opinion: https://hgecontraptions.blogspot.com/2018/10/ep-booster-modded-clone-120th-pedal.html
Drive 2&3 should be at row "I" on the inverting input
ReplyDeleteI just finished building it with the right drive pot connection and it works correctly, also the transistors symbols (not the pinouts) are reversed for 2N3904, thank you for making the layout of the latest "correct" schematic, It's a good sounding overdrive
DeleteThanks for the headsup about the gain control. Layout is updated and tagged.
DeleteNow the drive pot is reversed, 2&3 should be at row "i" and 1 at row "e"
DeleteThanks. Fixed.
DeleteThis comment has been removed by the author.
ReplyDeleteDid you intentionally omit the 100k in row 14? Just curious.
DeleteSorry, had an error with the link for some reason.
DeleteReposting here my build and answering your question below:
https://hgecontraptions.blogspot.com/2025/08/hge-contraptions-xotic-ac-booster-clone.html
You can omit the 100k output resistor to slightly lower the output impedance and get a bit more high-end clarity or let's say brightness, especially when driving long cables or low-impedance inputs. Also gives a little bit more level at the output, since we are basically removing a small series resistance, but it is less predictable, with different gear and also the potential for certain noise aspects like pops and whatnot can grow.
Just a personal preference, while in tests.
I might put it back to adhere to the original idea, who knows :D
I wanna change something else also so maybe will do that when I open it up again. I did test with and without, for kicks, and for my purpose it was a bit nicer without it.
Interesting. I've tried a couple Xotic builds but never felt satisfied with the results.
DeleteGotta be honest, I agree with you. I did the Xotic RC a long time ago for someone (also not impressed). I am also not impressed about the AC haha, but was just curious. I also did their Xotic EP Booster, but I did another version, as yet again their EP to me doesn't sound right with their stock bias, meh, but this is just my own opinion: https://hgecontraptions.blogspot.com/2018/10/ep-booster-modded-clone-120th-pedal.html
Deletehttps://www.youtube.com/watch?v=QP8sciuet6M&t=150s
The briggs modded + some other things mentioned in my post blog, is the nicest variant to my tastes.
Delete