nice Steve and Adriano
It looks like the only difference between the YJM and the 250 is the taming or anti oscillation cap in the FBL of the 741.
The only difference between the the MXR distortion + and the DOD 250 seem to be minor value changes.
Adriano which pin does the gain lug 1 go to on your YJM vero layout ?
And I should have includued a 10n to ground at the input of the super modded 250 I posted to cut down on hiss introduced at the input.
And I should have added the option of having the small value cap in the FBL of the 741 too.
There should be room to add those by just drilling some extra holes in the existing layout,
But looking at it again I also see where I could have made the layout even better and more compact.
I may do another smaller version to use 16 mm pots,and the other added mods later on.
AnalogMan says the extra 25pf cap is used in the 308 because they used a 4558 in the pedal (actually only half of the dual 4558 IC), which has a wider frequency range than the original 741 IC. The added cap attempts to make the 4558 sound more like the 741 circuit, and isn't needed if you are using a 741 in there. One of his mods uses a 1458 instead of the 4558, which according to him is actually a dual version of the 741 chip, and sounds more like it in the circuit (and also doesn't need the 25pf cap). He says the 308 does sound a little noisier with the 1458 in place of the 4558, but closer in sound to the 741.
Maybe you are already aware of this, but you mentioned having the option of using the 25pf cap with the 741, which shouldn't be necessary.
Yeah your right Al,I was overlooking the use of different op amps,also
I was thinking in terms of reducing the hiss in the upper end of the frequency range,but that would detract from the "sound" of the 741 and it would also probably take something closer to a 50-100p cap to do that.(some breadboarding would be needed to say for sure)
nice catch on that thanks.
@Steve, No I think those YJM layouts are good here
,so is the list of artist who use the pedals,even better a list of albums and tracks to give an idea of the sound in the right hands with the right amps.
I also think if you still have them ? Pics of the outside and inside of the different models in chronological order would be a really cool addition to this thread.