MarginalPlayer
New member
Many thanks again to @Cybercow, @VivekMEHTA, @caspercody, @JTEX, everyone on this forum, and other DIY pedal forums who shared information on this circuit....a trip back to the 1980's. The blue Hi N' Dry is my second attempt at building the front end of the X100. A long process with numerous interruptions, but I'm calling it 97% done. For this version, I cheated and used the PedalPCB 3PDT Charge Pump board to supply +/- 9VDC versus the original +/-6VDC. Using the original schematic terminology, R176 was socketed and upsized slightly to compensate for the higher voltage. I understand there is a limitation with the charge pump having enough umph to power a complete X100 with chorus/echo/stereo, but it seems to work ok with just the front end.
This wasn't a complete success, the biggest gremlin was some noise/hiss in the clean channels. Maybe the original version had some of this too(?), there is a whole bunch of spaghetti in the box, and using stripboard also isn't helping with noise. My original clean/distortion switching arrangement used a duplicate R174 to make the switching work with a 4PDT stomp switch. I still am not sure of the best way to truncate the partial circuit and add a volume control, but I used the spare op amp on the distortion section's 072 chip as a simple output buffer/filter, which probably wasn't the best idea (sharing chip with high gain). There seemed to be some faint bleed through of the distortion into the clean channels, so I changed my switching to completely disable the distortion section while using the cleans. This fixed the bleed through, but the penalty is that the edge switch needs to be on while using the clean channels to duplicate the original circuit.
I tried various other things to reduce noise, swapping op amps, testing various jfets, reducing power to 6V, etc. I also tested the "hidden X100 noise gate?" circuit discussed in Cybercow's "Understanding a Specific Circuit (Analysis Assistance Please)" post, but after everything there is still some remaining hiss in the clean channels. I own the finest Les Paul copy that $150 can buy, and it also seems the clean channels don't like my bridge pickup too well, and the neck pickup sounds much better with the cleans. The EQ switching arrangement using a DPDT toggle also allows distortion/edge to use EQ 2 as a bonus.
Please don't look too close, the paint / decal isn't perfect, drill bit wandered a little, lots of rework on the stripboard, messed up a trace on the charge pump board, etc. I'm just a guy who likes to tinker and I don't have the best ear, but it sounds very similar to the Proposition and my orange DIY attempt 1. If I do a version 3, I will try a different output buffer arrangement (probably should ask for some help here?) or use a tone-tweq board and revisit the clean/distortion switching setup. I like the compression on, so I would probably not install an external compression control to keep the offboard wiring a little simpler. Thanks All!
This wasn't a complete success, the biggest gremlin was some noise/hiss in the clean channels. Maybe the original version had some of this too(?), there is a whole bunch of spaghetti in the box, and using stripboard also isn't helping with noise. My original clean/distortion switching arrangement used a duplicate R174 to make the switching work with a 4PDT stomp switch. I still am not sure of the best way to truncate the partial circuit and add a volume control, but I used the spare op amp on the distortion section's 072 chip as a simple output buffer/filter, which probably wasn't the best idea (sharing chip with high gain). There seemed to be some faint bleed through of the distortion into the clean channels, so I changed my switching to completely disable the distortion section while using the cleans. This fixed the bleed through, but the penalty is that the edge switch needs to be on while using the clean channels to duplicate the original circuit.
I tried various other things to reduce noise, swapping op amps, testing various jfets, reducing power to 6V, etc. I also tested the "hidden X100 noise gate?" circuit discussed in Cybercow's "Understanding a Specific Circuit (Analysis Assistance Please)" post, but after everything there is still some remaining hiss in the clean channels. I own the finest Les Paul copy that $150 can buy, and it also seems the clean channels don't like my bridge pickup too well, and the neck pickup sounds much better with the cleans. The EQ switching arrangement using a DPDT toggle also allows distortion/edge to use EQ 2 as a bonus.
Please don't look too close, the paint / decal isn't perfect, drill bit wandered a little, lots of rework on the stripboard, messed up a trace on the charge pump board, etc. I'm just a guy who likes to tinker and I don't have the best ear, but it sounds very similar to the Proposition and my orange DIY attempt 1. If I do a version 3, I will try a different output buffer arrangement (probably should ask for some help here?) or use a tone-tweq board and revisit the clean/distortion switching setup. I like the compression on, so I would probably not install an external compression control to keep the offboard wiring a little simpler. Thanks All!
