The schematic for this effect was recently posted on FSB and here’s a companion vero layout if you want to try it out. From what I hear the Cornish stuff is quite sought, not necessarily an indicator of quality of course 😉 Let me know if you build it and how you like it.
Update (20.01.2013): Now verified, thanks to Benno.
Also…try tl071 on this one!!
Well I finally have some conclusions.
My problem was with the C13. Replaced and worked perfect.
I think I have to change the drive potentiometer also, because I have the same issue as michael. About the volume pot, michael I believe the problem is the diodes.
I tried quite a few though. I think I’ll stick with the 1N914s they sounded the best on my ears (smoother). I also liked the 1N270s. 1N34A had very low output (volume), I also tried double 1N34As which sounded nice. 4148s where kind of dark and LEDs also, but the LEDs where amazing with the drive full.
One again thanx Harald
Stavros, here’s the schematic I based this on: http://www.freestompboxes.org/viewtopic.php?f=7&t=16071&hilit=cornish+ss+2&start=40#p211266
I took a look at the first schematic I googled, and I saw few differences on some values. I know if I should doubt for the schematic, but C1 from 10n to 220n is big difference.
Would it be possible that a case like that could cause my problem? Of course I didn’t had the time to troubleshoot on my build, I got bored at work so I do some theoretical troubleshooting 🙂
Could you tell me what schematic you used…just for my curiosity
Hi Stravos,
No idea whatsoever. I’d love to hear what you find out about it, though.
This worked from the first try. But, the sound just faded out after a couple of minutes. No sound since then…any clue of what to see before I start desoldering capacitors?
Hi michael,
You can try the C50k drive pot, sure. Swapping out the volume pot for another value isn’t going to help you, though, since it’s just an attenuation control and not part of an active amplification stage. Instead you could try increasing R14 (6k8), a 68k should give you 10x gain, but might also change the sound and how the effect works. You’ll have to experiment.
hi to all friends, i built the ss2 and sounds great , the only problem with a 50KA pot on the gain the pedal has a smooth and gradually gain but whe you reach the 3’o clock and after the gain goes very high like crazy in the last 25% of the pot and someone could not control very gradually. Do you think a 50kC reverce log pot will help a little on it?
The max volume is a bit low too for my equipment amp etc i need the 75% and mybe 100% of volume pot to have satisfied level of volume , i rhink if a 100KA pot help and gine a bit more volume ..
Thank you very much
I’m not sure what semiconductor manufacturers make a 741 single opamp, but any make will probably do.
Sorry for my ignorance but, by 741 you mean LM741 right?Any alternatives?
Great! Thanks for verifying, Benno 🙂
Well I couldn’t find it so I built another one, and it works!! Then I noticed a wrong resistor value on the first build, so you can call this verified twice!!! I used different pot tapers between builds and can recommend using C taper for drive, and B taper for tone, using log for those didn’t work very well. Thanks for the layout, sounds great by the way.
Hi,Benno:
I think when you said if you use your finger and go from row to row, you get something.
That sound like “you” are completeing the cct. So you have something no quite right.
I often say to myself I have everything right and then after looking at it for a third time, i find that i did something wrong.( resistor went one row too many/less, stuff like that. Or maye a solder blob in between a row.
In Haralds vero’s he is 99% correct when he goes from a schematic to his vero layouts and i always trust what he gives us. Step away from it for an hour then come back an look at your cct again, good luck
Benno, not sure what to think of this one. Hmm.
Because of D3 you should have continuity from the +v strip (a) to ground, but only the “wrong” way. If you measure from the “+9v” board label you should not have any continuity however (because of D4). Could one of your caps be shorted perhaps? I have to admit I don’t know a good way to approach this problem.
Hi Harald, I’ve built this up but having a problem. When I connect to power it has sound for about 3 seconds then disappears into fuzz then silence with slight fizz. If I touch row G and H with my finger the sound comes back then fizzes out again. Any ideas?. I’ve been over it with DMM and noticed with power connected to the circuit there is continuity between ground and 9V. I’m stumped!! Thanks mate, love your work.
Hi Glenn, apparently the comment section was broken over a couple of days without me noticing, so thanks for being the first one 🙂
Not going to reveal the amp details until I know whether it works or not, or I’d be terribly embarrassed, but I can reveal that I started off with the Hot Cat 30 schematic as a base, and then there’s a lot of changes on top of that.
Haven’t decided yet, but I might try tweeting/posting pictures as the build progresses. We’ll see 😉
Thanks for the nice words re. site!
Hi, Harald, no one left you a comment on this yet. Even though I have too many tube-screamer/OD’s….I want to say thanks for the layout, and i like the look of your re-vamped for 2013 web site. Cheers Bro.
I did build the other Cornish layout but its dark sounding and i sorta lost interest in it, but when i have some time,i will look at it again. oh yeah what going on with all those amp parts? Come on and give us a hint of what your building…Ha ha