MI Audio Super Crunch Box  [traced]

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MI Audio Super Crunch Box

Postby roseblood11 » 04 Dec 2015, 23:57

Is it really true that this version hasn't been retraced yet?
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Re: MI Audio Super Crunch Box

Postby MoonWatcher » 03 Jan 2016, 19:02

roseblood11 wrote:Is it really true that this version hasn't been retraced yet?
https://www.youtube.com/watch?v=smZmzy8fXc4

Retraced - good choice of words! :thumbsup

Not sure a tracing would really be necessary. I'd think that 90% is as the Crunch Box has already been for years.

The presence control has finally been put topside instead of as an internal trimmer - probably has same component values.

3-way toggle - probably LED/none/silicon clipping diodes. It's really more of a personal flavor thing beyond the standard LED-type clipping, so I'm (personally) not really curious as to what the "new" diodes in the third setting actually are.

High and Low gain selections - lots of standard ways to achieve that - probably toggles a different resistor value at IC1B's negative feedback loop. Most of these Guvnor-based pedals seem to use 1M, and the real thing probably isn't that much lower gain with 680k. So, just a guess, but maybe it's even lower at 470k/510k/560k - I guess it was tuned a little bit to be a good alternative to the higher gain setting.

I didn't really hear any different voicing in the video vs. the version 1, so I'd assume that nothing was changed that would cause that. Given the popularity and pretty basic expectations with the Crunch Box (lots of distortion, sound sort of like a Marshall amp), I really couldn't imagine that anything was actually changed. It really just sounds like it has more controls vs. the original 3-knob version.
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Re: MI Audio Super Crunch Box

Postby J0K3RX » 21 Jan 2016, 18:31

Probably because they want to hide something... :hmmm:

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Re: MI Audio Super Crunch Box

Postby moonshiner » 23 Jan 2017, 18:24

I think its funny the guy that copied the marshall guvnor gooped his board . It is a very excellent retake on the Guvnor for sure though
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Re: MI Audio Super Crunch Box

Postby roseblood11 » 23 Jan 2017, 21:10

It's not really a copy. It uses opamps and LED's to build a clipping circuit, but the gain structure and the tonestack are different. The Guv'nor wasn't bad, but to put an "amp style" tonestack in front of a real amp with tonestack isn't always a good idea. Often the Crunchbox works better, although it has less controls. So, I would call it an improvemnt or a variation, not a clone
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Re: MI Audio Super Crunch Box

Postby michael_ibrahim » 24 Jan 2017, 00:12

roseblood11 wrote:It's not really a copy. It uses opamps and LED's to build a clipping circuit, but the gain structure and the tonestack are different. The Guv'nor wasn't bad, but to put an "amp style" tonestack in front of a real amp with tonestack isn't always a good idea. Often the Crunchbox works better, although it has less controls. So, I would call it an improvemnt or a variation, not a clone


Thank you!
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Re: MI Audio Super Crunch Box  [traced]

Postby FuzzMonkey » 24 Jan 2017, 01:54

I found this a while back:

Image
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Re: MI Audio Super Crunch Box

Postby roseblood11 » 24 Jan 2017, 01:55

Aion electronics offers a pcb for that
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Re: MI Audio Super Crunch Box

Postby michael_ibrahim » 24 Jan 2017, 02:22

Ah,... You've just solved a mystery for me! I was wondering what the Andy Timmons JHS pedal was. It's this design without the charge pump.
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Re: MI Audio Super Crunch Box

Postby ivan H » 28 Aug 2017, 10:22

I see there's a V2 of the Super Crunchbox out now that adds an active 3 band eq section instead of the tone control & another low gain option, making 3 switchable gain options. Still 3 selectable compression options, though the write up lists one as a "Jose" type clipper. Not sure if that's still the original silicon diode setting or not, Jose Arredondo did many variations on clippers, zeners, silicon diodes or a combination of. Just wondering if anyone has had a peek inside a V2 yet. I just finished boxing up a point to point perfboard super Crunchbox. By repositioning the two switches I could fit a 3 band eq in, most likely. Cheers
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Re: MI Audio Super Crunch Box

Postby Rogerio » 22 Jul 2019, 22:20

Hi,

I’m very interested in the hi/lo gain feature. I ‘ve built a crunchbox in a breadboard, and I changed some resistors even capacitors, but the results are’nt convincing. Do you have any clue?

Thx

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Re: MI Audio Super Crunch Box

Postby michael_ibrahim » 24 Jul 2019, 11:02

I do!
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