Evilarsen traced a unit from 2015 last week and not surptisngly, it is a Rat derivate. However, the "One" and "Two" controls should give you more tonal options than a stock Rat.
And done. You can tag it. Great sounding rat variant especially on bass. I socketed the LEDs so I can play around with them a little. I wish I would have done the same with the 914s bit I was on a mission . Gonna put it in a 125b with top jax. Thanks for another great one.
well at first I didnt hear much of a difference, very subtle. But THEN I switched out the red LEDs for water clear green. That made the One and Two controls come to life for me. Before switching the leds out I could have probably lived with 1 control but now I really like having the 2. Green might not be for everyone , its my flavor of choice. I highly recommend socketing and adjusting to taste
Just to be clear control 1 & 2 do effect different frequencies. Its a nice feature. Havent tested through amp yet, just headphones. I will do that L8tr today Matt
Simple other mod, the optional feedback loop offered by Fuzzrocious. Take a B1M pot, lug 3 go to lug 3 of the volume pot (G16). Lug 2 go to a 2PDT footswich and go to input (J1).
Struggling getting this to work properly, I can get sound but the switch doesn't make much difference to the tone and all sound cuts out completely when Distortion is turned up, can't even get it to noon. Can I ask if the vero layout is right? If I'm reading it correctly it looks like Dist 1 connects back to Dist 2&3 via the 100pf cap then the link on the 3rd column? If there's a schematic that would help.
Thanks, images here: https://freeimage.host/i/QD2Tj1 https://freeimage.host/i/QD25Ga For clarity, the red 10nf cap is wired correctly across 2 rows, not 3 as it appears from top view. Also the big 1uf cap is wired on the right row, it was just to big to fit without twisting. Currently have 2 red leds socketed but I've tried with greens and have the same issue.
Only thing I can think of is my wiring for the 'Switch 2 and Filter 2&3' - I've wired from the vero to filter 3, then bridged to Filter 2, then wired from Filter 2 to Switch 2. So they're all connected but I'm guessing maybe thats the wrong order?
Please if anyone can guess why the sound would cut out completely when Distortion is turned up I'm open to any suggestions. I've used this for the offboard wiring: https://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html) https://freeimage.host/i/QD2Tj1 https://freeimage.host/i/QD25Ga
Ok this is weird, so I just swapped the wires going to Switch 1 and Switch 3, not sure why, I just did it randomly (!) and now the Distortion pot can be turned further before all sound cuts out. Originally sound was cutting out when Distortion got to about a quarter of the way, now sound cuts out at around 3 quarters. This is happening no matter what position the switch is in so I'm a bit baffled.
The switch itself works fine, I'm getting different clipping from it in each position, and the red leds light up when its switched to them. In fact everything works fine, all the knobs affect the sound the right way, its just that the distortion, when beyond about 75%, causes all sound to cut out. The only difference in my components is that I'm using an LM308N.
I'm currently troubleshooting this build after getting the same distortion issue as Trainbusker. As soon as I turn the distortion up the audio cuts out. I've verified the A100k pot works like it should with a DMM, swapped the IC and transistor, and used new capacitors/resistors on a 2nd fresh build without success. Pin values seem to be OK with 2, 3 and 6 showing 3.01v with distortion CCW and 7.58v with distortion CW. Transistor values are 0, 1.86, and 8.18v GSD. Audio probe shows loss of signal at pin 6.
I've also traced this layout and compared it to the known Rat schematic- only a few issues on this layout that I could find, in order of decreasing importance: 1. The 2.2u capacitor is backwards- negative pole should be to the right. 2. The 1K resistor on row 13 is typically 10k on most Rat schematics. 3. There's usually a 47R resistor inline with the protection diode to serve as a noise filter.
Only other mods I've made are using the OPO7 IC instead of the LM308, eliminating the 33p cap on the second build, and eliminating the clipping switch (for now) by bridging K and M with the LEDs- my plan is to use an 8 way knob for multiple clipping options (similar to the Black Mass 1312) once the board works.
I'm gonna keep working at it but wanted to let others know my struggles. Will post if I get it working.
Thanks for posting this one!!!!! I've become obsessed with trying out different Rat variations lately.
Built today and it fired up right away! I had to steal an OPO7 from another build to test. The only changes I made (due to necessity) - I used a socketed 1uf radial (didn't have a 2.2u) and I socketed a 47pf (didn't have a 33pf). I also socketed the 3mm red LED's and am going to play around with different colors. I have LM308N's and OPO7's on order right now so plan to test this a little more once I have them and an enclosure but it sounds awesome so far!
Bulding this for my bass board (Brian Cook has one, so it's gotta be great) I'm getting the same issues as Trainbusker and runStl. It's gotta be in the layout/schematic.
I built this around the end of last year, using the above layout, and it works for me no problem. A couple of differences in mine: - as others have noted, the 2u2 cap in the top row should have the negative leg on the right. - didn't have any LM308s or OP07s on hand, but it worked just fine with a TL071, LM741, and CA3130EZ. Beyond the usual advice of checking for bridges, making sure your cuts are complete, etc., I'd say check your pots. For some reason, recently I and a couple of friends have been having unusually high rates of failure for A-taper pots.
And done. You can tag it. Great sounding rat variant especially on bass. I socketed the LEDs so I can play around with them a little. I wish I would have done the same with the 914s bit I was on a mission . Gonna put it in a 125b with top jax. Thanks for another great one.
ReplyDeleteFhabks Matt! Will tag it.
DeleteSo what do you think about the "One" and "Two" controls?
well at first I didnt hear much of a difference, very subtle. But THEN I switched out the red LEDs for water clear green. That made the One and Two controls come to life for me. Before switching the leds out I could have probably lived with 1 control but now I really like having the 2. Green might not be for everyone , its my flavor of choice. I highly recommend socketing and adjusting to taste
ReplyDeleteJust to be clear control 1 & 2 do effect different frequencies. Its a nice feature. Havent tested through amp yet, just headphones. I will do that L8tr today
DeleteMatt
Simple other mod, the optional feedback loop offered by Fuzzrocious.
ReplyDeleteTake a B1M pot, lug 3 go to lug 3 of the volume pot (G16). Lug 2 go to a 2PDT footswich and go to input (J1).
hi Fuzzhead, may i ask you for the schematic? cheers
ReplyDeleteI'll ask evilarsen if he can send it to to me or post a link here.
DeleteAmazing thanks!! I Hope he can share it !
DeleteDid you ever get the schematic? Late to the party but it'd be awesome to get it haha
DeleteHi. What would I change on this layout to NOT include the One and Two controls?
ReplyDeleteStruggling getting this to work properly, I can get sound but the switch doesn't make much difference to the tone and all sound cuts out completely when Distortion is turned up, can't even get it to noon. Can I ask if the vero layout is right? If I'm reading it correctly it looks like Dist 1 connects back to Dist 2&3 via the 100pf cap then the link on the 3rd column? If there's a schematic that would help.
ReplyDeleteIf you can link a hi res pic of your build front and back we could better help troubleshoot
DeleteThanks, images here:
Deletehttps://freeimage.host/i/QD2Tj1
https://freeimage.host/i/QD25Ga
For clarity, the red 10nf cap is wired correctly across 2 rows, not 3 as it appears from top view. Also the big 1uf cap is wired on the right row, it was just to big to fit without twisting. Currently have 2 red leds socketed but I've tried with greens and have the same issue.
Only thing I can think of is my wiring for the 'Switch 2 and Filter 2&3' - I've wired from the vero to filter 3, then bridged to Filter 2, then wired from Filter 2 to Switch 2. So they're all connected but I'm guessing maybe thats the wrong order?
DeleteSwitch 2 needs to go to the board, not to the pot
DeleteThis comment has been removed by the author.
ReplyDeletePlease if anyone can guess why the sound would cut out completely when Distortion is turned up I'm open to any suggestions. I've used this for the offboard wiring: https://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html)
ReplyDeletehttps://freeimage.host/i/QD2Tj1
https://freeimage.host/i/QD25Ga
Board looks good, I would say check your pot wiring
DeleteOk this is weird, so I just swapped the wires going to Switch 1 and Switch 3, not sure why, I just did it randomly (!) and now the Distortion pot can be turned further before all sound cuts out. Originally sound was cutting out when Distortion got to about a quarter of the way, now sound cuts out at around 3 quarters. This is happening no matter what position the switch is in so I'm a bit baffled.
DeleteHave you tried replacing the switch altogether? Switch lugs are just held in place by epoxy - so heat can shift the lugs fairly easily.
DeleteThe switch itself works fine, I'm getting different clipping from it in each position, and the red leds light up when its switched to them. In fact everything works fine, all the knobs affect the sound the right way, its just that the distortion, when beyond about 75%, causes all sound to cut out. The only difference in my components is that I'm using an LM308N.
DeleteIt sounds like a bad connection somewhere. It could be a bad pot or one of the other off board connections.
DeleteI'm currently troubleshooting this build after getting the same distortion issue as Trainbusker. As soon as I turn the distortion up the audio cuts out. I've verified the A100k pot works like it should with a DMM, swapped the IC and transistor, and used new capacitors/resistors on a 2nd fresh build without success. Pin values seem to be OK with 2, 3 and 6 showing 3.01v with distortion CCW and 7.58v with distortion CW. Transistor values are 0, 1.86, and 8.18v GSD. Audio probe shows loss of signal at pin 6.
ReplyDeleteI've also traced this layout and compared it to the known Rat schematic- only a few issues on this layout that I could find, in order of decreasing importance:
1. The 2.2u capacitor is backwards- negative pole should be to the right.
2. The 1K resistor on row 13 is typically 10k on most Rat schematics.
3. There's usually a 47R resistor inline with the protection diode to serve as a noise filter.
Only other mods I've made are using the OPO7 IC instead of the LM308, eliminating the 33p cap on the second build, and eliminating the clipping switch (for now) by bridging K and M with the LEDs- my plan is to use an 8 way knob for multiple clipping options (similar to the Black Mass 1312) once the board works.
I'm gonna keep working at it but wanted to let others know my struggles. Will post if I get it working.
Thanks for posting this one!!!!! I've become obsessed with trying out different Rat variations lately.
ReplyDeleteBuilt today and it fired up right away! I had to steal an OPO7 from another build to test. The only changes I made (due to necessity) - I used a socketed 1uf radial (didn't have a 2.2u) and I socketed a 47pf (didn't have a 33pf). I also socketed the 3mm red LED's and am going to play around with different colors. I have LM308N's and OPO7's on order right now so plan to test this a little more once I have them and an enclosure but it sounds awesome so far!
Bulding this for my bass board (Brian Cook has one, so it's gotta be great) I'm getting the same issues as Trainbusker and runStl. It's gotta be in the layout/schematic.
ReplyDeleteYep, you are right. There was a typo in the schematic. The 1k between D2 and D3 should be 10k. The layout is updated.
DeleteThis comment has been removed by the author.
DeleteWere you able to get this working? I just ran into the same issue.
DeleteI built this around the end of last year, using the above layout, and it works for me no problem. A couple of differences in mine:
Delete- as others have noted, the 2u2 cap in the top row should have the negative leg on the right.
- didn't have any LM308s or OP07s on hand, but it worked just fine with a TL071, LM741, and CA3130EZ.
Beyond the usual advice of checking for bridges, making sure your cuts are complete, etc., I'd say check your pots. For some reason, recently I and a couple of friends have been having unusually high rates of failure for A-taper pots.
Reversing the 2u2 fixed it! Thank you so much!
DeleteThis comment has been removed by the author.
ReplyDelete