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Vintage threads from the first ten years

Big Muff

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6/18/1999 4:11 PM
Terry	Big Muff I am strongly thinking about building the Big Muff (Pi)distortion....i'd rather not work with IC's.....is the transistor version much different than the opamp version? i also have 2 schematics for the Big Muff, can anyone tell me which one is the original (if any)? THANx

6/18/1999 8:23 PM

Re: Big Muff (R.G.)

The transistor version is completely different from the opamp version. Not even similar.

If you'll tell me where you are getting schematics from, I may be able to help more.

In the case of the BMP, it is almost impossible to say one version is "original" because EH is notorious for building pedals from whatever was at hand. They'd send employees out to surplus stores to get whatever was there and would work. This makes it very difficult to look at two and say which was earlier. There are a large number of variations.

6/20/1999 9:51 AM
anonymous	Do you have any opinions on the differences between the transistor and the opamp version??

6/20/1999 8:26 PM
R..G.	Very strongly. Don't bother with the IC version. Build the transistor one.

6/20/1999 11:27 PM

Re: Big Muff IC vs. trans

It´s all in taste....

Maybe the transistor version is more "musical" (whatever that means, heheh) but I have an IC version laying around that needed work on the hacked-in power-supply (which I STILL haven´t done, but that´s another story)

This thing is definitely a one-trick pony, but so is the trans. version. About the most over-the-top huge wall of distortion a la Pumpkins I ever got out of a pedal.

On the other hand, I´d sooner build the trans. version too, probably - and it´s simpler, too.

6/22/1999 5:18 PM

Re: Big Muff (R.G.)

Seconded...if only for convenience. Putting together a circuit on perfboard is much easier with transistors than with IC's, since you can wrap the transistor leads around the legs of any connecting caps, and don't have to worry quite so much about the orientation of components (that's direction NOT polarity, folks). Wire=wrapping IC circuits on perfboard is quite do-able (I've done dozens and dozens), but the transistor BMP is something you can do in a short evening. It's that straightforward.

The transistor version is tried and true, with lots of optins for mods. For example, lifting one pair of diodes from the circuit will change the character of the distortion (also the fundamental difference between the Sola Tonebender...well, ONE of those tonebenders...and the EH-BMP).

As for one-trick-pony qualities, I've found mine to be quite decent at very mild grind in addition to over-the-top sounds. The trick would seem to be getting your settings right, and putting a small value resistor (100-470R) between the ground lug of the gain/drive/sustain control and ground. This will set the minimum amount of drive going to the next stage, but will also give a little more specificity when dialing in low distortion sounds (i.e., settings between 7 o'clock and 8 o'clock are meaningful and obtainable differences).

6/21/1999 0:19 AM
Terry	Do know where i could get this .bmp schematic? i've only seen the common gif.. and postscript ones

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