MXR - El Grande Bass Fuzz

sevinisthenumber · Post by **sevinisthenumber** » 18 May 2010, 18:58

Brainbender wrote:i have. it's my original scan of origonal schematic. i'll post it later. cheers!

excellent!

Brainbender · Post by **Brainbender** » 19 May 2010, 09:47

Here you go, folks! Hope you'll enjoy it and i hope you will make some layout! I would do that, but i'm a total noob!

Btw. Just want you to remember... It's an original schematic!

http://www.box.net/shared/sdg9hlq6aq

Cheers!

: El Grand Bass Fuzz schematic

gkoerselman · Post by **gkoerselman** » 19 May 2010, 12:24

Thanks for the schematic!

MMBF170 = BS170
MMBTA14 = MPSA14
MPQ3904 = 4x 2N3904
MMBT5088 = 2N5088

Did I get that right (please mark the underlined as different to the schematic)...?

celadine · Post by **celadine** » 23 May 2010, 16:00

I think its MMBF177, not -170. Google says its probably = J177, PFET.

Otherwise - shit, what else is left to do with the BMP circuit? PNP Muffs, mixing transistor types, diode substitutions, tuning cap/resistor values, now we have: paralleled transistors.

Güero 2.0 · Post by **Güero 2.0** » 07 Jun 2010, 03:25

Hi,

This my layout for El Grande Bass Fuzz.
The internal trimpot and switch are now outside the pedal.
I removed the "millenium alike" that you find in the original schematic.
http://www.handmades.com.br/forum/inde ... ttach=2102

enjoy!

gigelmargel · Post by **gigelmargel** » 07 Jun 2010, 06:58

Güero 2.0 wrote:Hi,

This my layout for El Grande Bass Fuzz.
The internal trimpot and switch are now outside the pedal.
I removed the "millenium alike" that you find in the original schematic.
http://www.handmades.com.br/forum/inde ... ttach=2102

enjoy!

I can't download it

It request me to register, but when I try it says that no news registrations are possible

Brainbender · Post by **Brainbender** » 07 Jun 2010, 08:31

Same here!!!

@ Güero 2.0!!
You can send it to grungefuzz@gmail.com and i'll post it to Box.net or you can register there and upload it by yourself! It's very easy!

Güero 2.0 · Post by **Güero 2.0** » 07 Jun 2010, 13:57

Brainbender wrote:Same here!!!

@ Güero 2.0!!
You can send it to grungefuzz@gmail.com and i'll post it to Box.net or you can register there and upload it by yourself! It's very easy!

Check your inbox !

Or try this!

http://uploaddearquivos.com.br/download ... _Guero.pdf

Brainbender · Post by **Brainbender** » 07 Jun 2010, 14:20

Thank you so much, Güero!!! It's so neatly done!

I recived it by e-mail, but your link is also functional now! I'll also post it on Box.net, just to make more links!

Btw. I suppose it's a verified pcb, right?

Layout by Güero 2.0:
http://www.box.net/shared/30jfjuk1i4

gigelmargel · Post by **gigelmargel** » 07 Jun 2010, 20:39

very nice...thank you very much!

Fender3D · Post by **Fender3D** » 07 Jun 2010, 21:31

celadine wrote:I think its MMBF177, not -170. Google says its probably = J177, PFET.

Otherwise - shit, what else is left to do with the BMP circuit? PNP Muffs, mixing transistor types, diode substitutions, tuning cap/resistor values, now we have: paralleled transistors.

I remember an old ('70) Elektor's article explaining how increase the s/n ratio connecting several transistors in parallel

Güero 2.0 · Post by **Güero 2.0** » 07 Jun 2010, 23:50

Brainbender wrote: Btw. I suppose it's a verified pcb, right?

Until now I don't have time to build it.
But I revised a few times both the layout and conections.

Güero 2.0 · Post by **Güero 2.0** » 08 Jun 2010, 02:05

I've been thinking ....
And if we had only the DEEP circuitry of this pedal?

We'll have just a low frequencies boost , which is already great for some.
To get more volume in the output ,increase R34 value and test until you find the best result of volume and no distortion.

http://uploaddearquivos.com.br/download ... _Guero.pdf

R.G. · Post by **R.G.** » 08 Jun 2010, 02:13

Fender3D wrote:
celadine wrote:I think its MMBF177, not -170. Google says its probably = J177, PFET.

Otherwise - shit, what else is left to do with the BMP circuit? PNP Muffs, mixing transistor types, diode substitutions, tuning cap/resistor values, now we have: paralleled transistors.
I remember an old ('70) Elektor's article explaining how increase the s/n ratio connecting several transistors in parallel

They're there for piggybacking to lower the apparent gain of the amplifier transistors. I posted that in the other forum a few years back, like the Millenium Bypass.

I speculated that a dummy transistor paralleling an active one would suck out some of its base current an lower the apparent gain. Another fellow found the valuable bit of info that you can tune in any apparent gain you'd like by putting a resistor between the emitters. The dummy transistor lowers gain much more than half as I thought it would. That's because of the current difference (*I think*) and the difference in the internal apparent emitter resistance. Maybe. Possibly.

bajaman · Post by **bajaman** » 08 Jun 2010, 03:25

what did I miss

Excellent co-operation here - many thanks for sharing

bajaman

Sweetalk · Post by **Sweetalk** » 08 Jun 2010, 03:33

Really Nice, very Tonepad-like!. So, It's a big muff-like with paraleled transistors and a few other things?

Brainbender · Post by **Brainbender** » 08 Jun 2010, 13:19

@Guero: I'd like to thank you once more for your effort, because i sold my original pedal and i'll be able to do it by myself in near future (with some mad design on the enclosure

). Thanks!

@Sweetalk: I've heard that it's based on green russian Big muff...

BB

ddpawel · Post by **ddpawel** » 15 Jul 2011, 19:37

Brainbender wrote:Here you go, folks! Hope you'll enjoy it and i hope you will make some layout! I would do that, but i'm a total noob!
Btw. Just want you to remember... It's an original schematic!

http://www.box.net/shared/sdg9hlq6aq

Cheers!

It's not only original schematics. It's also a great one!
It's:
-DPDT
-true bypass
-led
-input to ground

I did' not expect you can get both LED and input to ground in DPDT-true-bypass.

Do you hear in this effect pedal some pop-noise when you switch it? Do you think it will fit into high-gain type pedal like Metal Zone (I've got a lot of Carling DPDT's so want to use one and have LED and input to ground when bypassed, so Grande Fuzz would be my salvation)?

Post by **azrael** » 16 Jul 2011, 04:07

So what's the advantage here of paralleled transistors? Just more gain, right? Why not just toy with the emitter resistor and input resistor for each gain stage, then?

Liquids · Post by **Liquids** » 16 Jul 2011, 16:03

azrael wrote:So what's the advantage here of paralleled transistors? Just more gain, right? Why not just toy with the emitter resistor and input resistor for each gain stage, then?

Actually it yields less gain...

MXR - El Grande Bass Fuzz [schematic]