Best Big Muff, and best transistors

[kristoffereide]

I'm overwhelmed by the amount of versions and mods to the BM, and I want to know which BM if the best build. I also want to know your experiences with different transistors. I've got AC128 Ge, 88' 89' 39 Si... Could any of these be used (not the Ge AND the Si of course) with good results?

[geertjacobs]

This question has been asked recently (and many many times before).

http://www.diystompboxes.com/smfforum/index.php?topic=78110.0

Mark Hammer: Said it before and I'll say it again: the quintessence of the BMP is the fact that it is essentially TWO diode clippers in a row.  Once you do that, and for the most part it really doesn't matter how you do it, the resulting sonic personality is pretty much established.  After that, it is simly a matter of EQ-ing, shaving off a bit of bass here or a bit of treble there.

Please check the search function for many more threads 

[thereverend]

"best", when it comes to the big muff, is extremely subjective. i've built 2 and i still like my russian muff i bought 12 or 13 years ago better.

[Meanderthal]

 They're all different, no two sound quite the same. Some (dare I say it) sound just awful, some sweet and smooth, some sputter and spit at you, some even sound remarkably fuzz-face-like. The best one is the one ya played 20 years ago that lit your imagination and made you want to recreate that sound.

Study the circuit, learn ALL the mods, socket everything, tune that puppy to YOUR taste! Time consuming, but VERY rewarding.

[kristoffereide]

They're all different, no two sound quite the same. Some (dare I say it) sound just awful, some sweet and smooth, some sputter and spit at you, some even sound remarkably fuzz-face-like. The best one is the one ya played 20 years ago that lit your imagination and made you want to recreate that sound.

Study the circuit, learn ALL the mods, socket everything, tune that puppy to YOUR taste! Time consuming, but VERY rewarding.

Thanks, I will!

However, I couldn't find an answer to my questions in the searches. What are the best transistors? Some say 88's some say 89's some say 39's and even jFets and increasing hFe. All my transistors of the same type (88 as one type, 89 as another etc) have the same hFe. Is this OK, or do I have to increase it?

Well... I'll try one by one and see for myself...

[Bucksears]

I'm in the middle of building some Big Muff (ahem) variants myself, as well as the GGG BMP and the GGG '70 Fuzz. I got some BC183C, BC550C, 2N5088 and 2N5089 transistors. Main thing is to check and see if they have enough gain; I've read that the 88's and 89's are all over the place. I think GEOFex's transistor gain checking circuit (originally intended for Ge trannies) works for Si trannies too; I hope so, cause that's what I intend to use to measure them out.
Marc Skreddy once wrote that anything over 300 hfe should work for a BMP, others go on to say that 500-600hfe really make it sing.

[anchovie]

Some say 88's some say 89's some say 39's and even jFets and increasing hFe.

There are going to be different groups of people with their own ideas of what BM sound they want (Dave Gilmour's lead tone, Smashing Pumpkins' heavy rhythm sound etc.).

How do you want it to sound?

[RDV]

I've got 3 of those Mullard OC140 NPN in mine. I used some that were too high-gain to make a good fuzzface. I really like the sound though it's not 100% different than with Si ones in there.

RDV

[kristoffereide]

How do you want it to sound?

Good point! Thanks

[zombiwoof]

I'm in the middle of building some Big Muff (ahem) variants myself, as well as the GGG BMP and the GGG '70 Fuzz. I got some BC183C, BC550C, 2N5088 and 2N5089 transistors. Main thing is to check and see if they have enough gain; I've read that the 88's and 89's are all over the place. I think GEOFex's transistor gain checking circuit (originally intended for Ge trannies) works for Si trannies too; I hope so, cause that's what I intend to use to measure them out.
Marc Skreddy once wrote that anything over 300 hfe should work for a BMP, others go on to say that 500-600hfe really make it sing.

Why would you use the Ge testing for a silicon transistor?  AFAIK, they don't have the leakage problems of Ge, I just measure them with my meter.  Am I wrong about this?

Al

[El Heisenberg]

I built a triangle version with the noise gate and tone bypass mods. I settled on mpsa18 for the buffers and 2n5133s for the clipping stage. Ive built three bmps and this is the best out of the three. Still nott satisfied. I built the tychobrae octavia, and the fuzz in that knocks the big muff outta the water.

[tjmicsak]

I'm in the middle of building some Big Muff (ahem) variants myself, as well as the GGG BMP and the GGG '70 Fuzz. I got some BC183C, BC550C, 2N5088 and 2N5089 transistors. Main thing is to check and see if they have enough gain; I've read that the 88's and 89's are all over the place. I think GEOFex's transistor gain checking circuit (originally intended for Ge trannies) works for Si trannies too; I hope so, cause that's what I intend to use to measure them out.
Marc Skreddy once wrote that anything over 300 hfe should work for a BMP, others go on to say that 500-600hfe really make it sing.

The RGKeen tester circuit will work for any transistor, but the original is for PNP trannys. For NPN you have to reverse the meter leads and reverse the battery polarity. After that, it is just the same use. I used alligator clips on a standard 9 volt clip and made spec resistor combinations on a perf board to be exactly the correct 2.2M and 2.472K. Be sure to have a battery that is right at 9 volts or close as most will be 9.5 or more new and the readings will be skewed  a bit. Depends on what you are measuring for but a difference of 10-20 hfe might make or break a tranny in some situations.

[brett]

Hi
The BMP is designed so that the tone is almost independent of the transistors used.  The transistors all run at much less than their maximum gain, and are biased well away from saturation and cutoff.  (Assuming that you aren't using monster power transistors or some other crazy thing).

However, many other components do have large effects. In particular, the series input and feedback resistors modify the gain.  The two feedback caps in the gain stages (usually 470/500pF) have a HUGE effect on tone.  Although I haven't explored this, I would expect that this is one position where cap type and tolerance can have a large effect.  Any cap distortion (such as hystersis) is being greatly amplified.  Any difference from the nominal value will result in a non-standard roll-off of high frequencies.  The difference between a "low" ceramic cap and a "high" ceramic cap is about 50%.  That's a big enough difference to make one BMP sound smooth (or mushy) and another sound bright (or hard).

I'm not suggesting that different transistors won't sound different.  But there's an old saying about not worrying about the mouse in your kitchen when an elephant is knocking the door down.

cheers

[Ibanezfoo]

I'm overwhelmed by the amount of versions and mods to the BM, and I want to know which BM if the best build. I also want to know your experiences with different transistors. I've got AC128 Ge, 88' 89' 39 Si... Could any of these be used (not the Ge AND the Si of course) with good results?

I have a newer commercial Russian model (black/yellow) and I built a couple others.  My favorite I built is the Ram head with 5088s.  To be honest, I bought the Russian model based on a recommendation and I never liked it.  I heard a bunch of clips of other models and thats why I built a few of my own.  The Russian version (at least the one I have) sounds like your guitar is coming from behind a stack of pillows or something.  Too fluffy and muffled sounding.  I guess to visualize I wanted an evil wolf with big spikey fur (which the Rams head seems to be) and the Russian is more like a big furry greazy wooly mammoth.   

[Ripthorn]

I've got one on the breadboard, looking get some of that Gilmourish goodness going on.  I think experimentation is half the fun and the only way to really get what you want.

[Ibanezfoo]

I'm overwhelmed by the amount of versions and mods to the BM, and I want to know which BM if the best build. I also want to know your experiences with different transistors. I've got AC128 Ge, 88' 89' 39 Si... Could any of these be used (not the Ge AND the Si of course) with good results?

I have a newer commercial Russian model (black/yellow) and I built a couple others.  My favorite I built is the Ram head with 5088s.  To be honest, I bought the Russian model based on a recommendation and I never liked it.  I heard a bunch of clips of other models and thats why I built a few of my own.  The Russian version (at least the one I have) sounds like your guitar is coming from behind a stack of pillows or something.  Too fluffy and muffled sounding.  I guess to visualize I wanted an evil wolf with big spikey fur (which the Rams head seems to be) and the Russian is more like a big furry greazy wooly mammoth.   

Sorry, when I wrote this I didn't realize there was actually a pedal called the wooly mammoth.  The Russian big muff sounds nothing like it.  The wooly mammoth actually sounds good, the russian big muff does not.... In my opinion      I was trying to convey a visual of the sounds.