Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)  [traced]

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Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)  [traced]

Postby culturejam » 16 Apr 2010, 18:44

At long last, here are the final results of the Tracer's Fund peek inside the Cornish G2.

Credit goes to Dirk Hendrik for the degoop and circuit trace and testing, and madbean for making up a pretty project file and an original PCB layout. Several other Fund members poked, prodded, and tested various schematics and layouts, and of course all members contributed financially to make the purchase.

An additional PCB layout may be forthcoming.

Have a look-see.

Cornish_G2_DEF.pdf

G2_01.jpg
G2_02.JPG
G2_03.JPG
G2_04.JPG
G2_05.JPG
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Last edited by modman on 10 Jun 2018, 12:47, edited 2 times in total.
Reason: Added the corrected and final schematic, re-uploaded board layout and component values pictures

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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby keto » 16 Apr 2010, 19:58

his site has a v1.5 layout up. Did not look for differences.
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby sinner » 16 Apr 2010, 20:57

60 downloads by last two hours, and no single fucking thank you? You guys rocks! It's so FSBish :roll:

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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby madbean » 16 Apr 2010, 21:21

Here's the updated version. Changes are only minor layout placements. All thanks go to Dirk for the heavy lifting.
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby devastator » 16 Apr 2010, 21:37

thanks !

very bad to see the truth . Just a modded version of big muff :? (even if the additional things can be interesting (input buffer and the different tone control). I don't know but I expected something more "personnal" or "worked" .
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby bajaman » 16 Apr 2010, 21:39

Once again excellent work by Dirk and Madbean and the fsb contributors fund :applause:
This is yet another example of why freestompboxes.org is THE BEST DIY FORUM on the planet :D
There is a whole LOT of useful information for budding DIYers and "solder jockeys" to learn from this G-2 reverse engineering, not just the electronic design but also the well laid out wiring and earthing practices that Pete Cornish uses. Thanks to all the members here who contributed financially to bring this project to fruition :thumbsup
And to all the other members who have yet to make any financial commitments, I say please consider doing so in the near future - even a very small contribution is always appreciated, and the more contributions, the more research and the faster the results appear for ALL members to share. Please always keep in mind that these results are published for educational and DIY purposes only and they should not be used by anybody wishing to compete commercially with the "reverse engineered" product 8) .
http://www.freestompboxes.org always welcomes healthy discussion and criticism but does not condone any commercial competition resulting from this or any other analysis of a commercial product published on this site.
Okay - now get your soldering iron hot and always remember as Bjorn Juhl of BJF effects says: "have fun!!!!" :thumbsup
Thanks
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby ech0es » 16 Apr 2010, 21:48

on the last image we can read "P-2/G-2 Pete Cornish 2005", so he uses the same pcb and layout for the two versions ?

It means the P2 is also a modded muff, but with other variations to have two different sounds
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby soulsonic » 16 Apr 2010, 22:01

Even though it's very simple, I like the way the tone control sounds in this circuit. It works just right for the smooth sound. I modded an old Maxon to be like this, and the results were very good.
It is funny how different a circuit can sound by just changing a few parts.

Thanks to Dirk, of course!
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby SPeter » 16 Apr 2010, 22:06

EXCELLENT!
THANKS A LOT TO ALL INVOLVED!
:applause: :applause: :applause:
:thumbsup
:D :horsey:
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby Jarno » 16 Apr 2010, 22:32

Great work, I was expecting some more electronics niftyness for the amount of money these units go for. And I can object to some aspects of the build, from a mechanical standpoint.

But indeed the best forum in the world for organising things like this!

Edit:

Looking at the pictures, there is one major point, and that's the cable harness. It's really thick and contains quite tight bend radii. It's heavy but not supported by tie-ing it to the enclosure.
Why is it so thick? Is it shielded? Inside an enclosure which is very EMI proof (but chopping a great big hole in it for the battery holder doesn't help, of course)?
"It crackles....., but that's ok"
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby Spewbag » 17 Apr 2010, 01:20

I don't really want to criticize here because 1. I didn't contribute and the people that did all did a great job and 2. I did not add any funds for this project........but next time maybe you guys should pick a pedal that for the most part isn't all ready known. I believe it was common knowledge that this was a tweaked BM and I'm sorry but I find most of the Pete Cornish stuff over hyped any how. :scratch: :hmmm: IMHO a good example was when the community here RE the BlackStone distortion.A relatively unique circuit that had been shrouded for some time.


Just my 2 bits.


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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby madbean » 17 Apr 2010, 01:51

Just to clarify Spew (lol): I think part of the motivation was to determine just how much of a tweak it was, and also to shed some light on the mysterious Cornish buffer of which there was quite a bit of interest. Second point is that the Blackstone was not a community project, but rather funded by me. Sorry to be picky.
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby Spewbag » 17 Apr 2010, 02:33

madbean wrote:Just to clarify Spew (lol): I think part of the motivation was to determine just how much of a tweak it was, and also to shed some light on the mysterious Cornish buffer of which there was quite a bit of interest. Second point is that the Blackstone was not a community project, but rather funded by me. Sorry to be picky.



That's fine, and again I really wasn't trying to be a douche.......It's just that IMHO it wasn't worth the price of admission(that damn stuff is criminally priced). As for muff tweaks....a muff is a muff is a muff. As for the Blackstone I was well aware that you did that(and appreciated it :thumbsup ). I was just using that as an example of a more worthy pedal.


No blood, no foul?


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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby madbean » 17 Apr 2010, 03:01

Spewbag wrote:
madbean wrote:Just to clarify Spew (lol): I think part of the motivation was to determine just how much of a tweak it was, and also to shed some light on the mysterious Cornish buffer of which there was quite a bit of interest. Second point is that the Blackstone was not a community project, but rather funded by me. Sorry to be picky.



That's fine, and again I really wasn't trying to be a douche.......It's just that IMHO it wasn't worth the price of admission(that damn stuff is criminally priced). As for muff tweaks....a muff is a muff is a muff. As for the Blackstone I was well aware that you did that(and appreciated it :thumbsup ). I was just using that as an example of a more worthy pedal.


No blood, no foul?


Spew


Of course....I was not implying anything like that, I'm sure you know. I have to agree on the totally overpriced BS. But, a large part of his clientele is obviously willing to pay for it (for better or worse). I also absolutely agree that future endeavors could most definitely focus on more original effects. Figuring out what those are is a bit of a challenge on its own!

As an aside, I will eventually get my crap together and get the Mojovibe done. Even though it's not unique, it is awesome sounding.
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Re: NSFW content and a thank you is what you tell your boss!

Postby noelgrassy » 17 Apr 2010, 03:13

Dirk Hendrik & madbean,
You two did an excellent job here. Both scraping and preserving the wee components must have been some task!
Thank you fellas, FSB Tracer Fund and Pete Cornish for the edification you bring us,

Noel Grassy.
Copyright does not protect facts, ideas, systems, or methods of operation, although it may protect the way these things are expressed. US Copyright Office

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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby Greg » 17 Apr 2010, 03:32

Spewbag wrote:........but next time maybe you guys should pick a pedal that for the most part isn't all ready known. I believe it was common knowledge that this was a tweaked BM and I'm sorry but I find most of the Pete Cornish stuff over hyped any how. :scratch: :hmmm: IMHO a good example was when the community here RE the BlackStone distortion.A relatively unique circuit that had been shrouded for some time.


Just my 2 bits.


Spew


Well.. the decision is based on a discussion followed by a vote, so Cornish was what people wanted.. admittedly we were hoping for a SS2, but availability made the decision for us.. and I think the result has killed most people's desire to do a Cornish again.
:D
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby Spewbag » 17 Apr 2010, 04:18

Greg_G wrote:
Spewbag wrote:........but next time maybe you guys should pick a pedal that for the most part isn't all ready known. I believe it was common knowledge that this was a tweaked BM and I'm sorry but I find most of the Pete Cornish stuff over hyped any how. :scratch: :hmmm: IMHO a good example was when the community here RE the BlackStone distortion.A relatively unique circuit that had been shrouded for some time.


Just my 2 bits.


Spew


Well.. the decision is based on a discussion followed by a vote, so Cornish was what people wanted.. admittedly we were hoping for a SS2, but availability made the decision for us.. and I think the result has killed most people's desire to do a Cornish again.
:D



LOL..........Nuff said I guess. :lol:
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby Spewbag » 17 Apr 2010, 04:22

madbean wrote:
Spewbag wrote:
madbean wrote:Just to clarify Spew (lol): I think part of the motivation was to determine just how much of a tweak it was, and also to shed some light on the mysterious Cornish buffer of which there was quite a bit of interest. Second point is that the Blackstone was not a community project, but rather funded by me. Sorry to be picky.



That's fine, and again I really wasn't trying to be a douche.......It's just that IMHO it wasn't worth the price of admission(that damn stuff is criminally priced). As for muff tweaks....a muff is a muff is a muff. As for the Blackstone I was well aware that you did that(and appreciated it :thumbsup ). I was just using that as an example of a more worthy pedal.


No blood, no foul?


Spew


Of course....I was not implying anything like that, I'm sure you know. I have to agree on the totally overpriced BS. But, a large part of his clientele is obviously willing to pay for it (for better or worse). I also absolutely agree that future endeavors could most definitely focus on more original effects. Figuring out what those are is a bit of a challenge on its own!

As an aside, I will eventually get my crap together and get the Mojovibe done. Even though it's not unique, it is awesome sounding.




Again, thanks for taking on the glorious burden..........I think one thing good came from this.....Folks out there should now know better to put there money back in there pocket and just say I'll pass.
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby culturejam » 17 Apr 2010, 05:09

Spewbag wrote:I think one thing good came from this.....Folks out there should now know better to put there money back in there pocket and just say I'll pass.

Maybe. But I think there is some very interesting stuff going on in the G2. The tone control is kinda cool, and using super lower v-drop diodes changes the tone.

And the multi-conductor shielded wire is nice. 8)
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Re: Cornish G2 - Guts, Schematic, Layout (from Tracer's Fund)

Postby mattpas » 17 Apr 2010, 05:19

I was wondering if the Sustain pot was a 47kA or a 470kA?
The schematic says 47k but the parts list states 470k
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