Hi evryone!
I have a couple questions that do not relate to each other but I wish I knew the answer...1) About the LM308 opamp used on the Rat pedal, which is a suitable replacement for it? I asked for the 308 on a parts supplier and he gave me a ridiculously high price, like ten times the price of a generic TL072. What gives? The pinout doesnt seem too standard either, at least from the schematics posted, so I assume I cant use any dual opamp... Same thing happened to me with the 741 on the Dod 250 (althogh this one is cheap, it dies quickly and has lots of noise) and other designs, are these different from the "industry standard pinout" or whatever its called?
2) I have a Tone Machine clone that I wish sounded cooler, the fuzz seems a little dull IMHO, dont get me wrong the thing works OK but I want to mod it. I know of a certain Prescription Electronics pedal that combines a Fuzz Face circuit with a Tone Machine octave section, with the diff that they are two independent FX( the 8ve can sound "clean" too), now the question is, how can I isolate the octave section of the Tone Machine? The circuit is stock as posted just evrywhere. My idea is to combine the 8ve with any fuzz I want or no fuzz at all.
Well, if anybody knows this, thanx a lot. Cheers!
the 308's a compensated OA...you use a small cap to set the gain on the highs [or is it cut] any you need a 308 or the workalike, I used the NTE cross ref IC. Check ou t the data sheet.
You could check out the Octave Screamer [a TS style transformer/diode] I haven't tried.
I have tried Bobtavia, Tychobrahe Octavia, the FTM [mine gets strong Octave] and need to start myself on the RM Octavia...a favored one among some octave fans. Green Ringer I have to close tolerance I think on the two each 68k's 22k's and diodes, IIRC the matching of these is recommended.
Clean Octave check GEO, much more difficult that a Fuzzy octave, which uses the conveniently clipped signal as part of the multiplying process....There's also a Dalekator which is said to be very wild...
Yea I've been working these octaves for a while and don't have one on the pedalboard yet.
I used the Tycho and FTM a couple of times but only for like the very end of "All Along the Watchtower"... does the fine finish on that one ppl seem to like but, they're just too rediculous for even occasional use...too much to drag around for just one cameo appearance...