New circuit, anyone feel like breadboarding today?

[JimRayden]

Could anyone give me any example circuits that have feedback loops on FETs. I'm trying to implement a "more drive" switch in the circuit.


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Jimbo

[GVC]

Still pretty new at this but I understand the Scematics and I am looking for some new guts for a 1590b that is set up for a DOD250 (I decided that is not for me).  This sounds interesting, but I need some help.  Could anyone post an updated shemo with the Gain pot and a layout for perf board would be cool but not necessary I guess.  I can fumble with the layout later.

Any more descriptions of how this sounds??? Guitars AMPS???

[MartyMart]

A gain pot would be wired as follows :
Off the source of Q1 (J201's middle pin) we replace the resistor to ground with a 5k log pot.
Lug three ( looking at the back lugs down its far left ) connects to the source pin
Lug two connects to the "+" side of the 4.7uf cap ( perhaps a 10uf even )
Lug one and "-" leg of that cap both connect to ground.
Done, instant gain pot.

Marty.

[JimRayden]

For your knowledge, this is a VERY fresh circuit and not fully tested yet. I would recommend you find an old good and widely built circuit you can find alot info for. This one is, let's say, not complete (although it sounds good). I'll test it on alot of guitars and amps on Friday, I'll let you guys know of the results and impressions of other guitarists I'm gonna meet. But if you wanna try it out, be my guest.

I was also thinking on taking it commercial, and as a rule, there are always people who search for places to cheat and sue someone to get cash (or at least a free pedal  ), so I'll have to ask to remove the schematics from the net. Further developement will occur offline. Better safe than sorry, I hope you guys understand.

Marty, could you please remove it.

If anyone has interest in the schemo, PM or e-mail me please.

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Jimbo

[MartyMart]

Marty, could you please remove it.

Jimbo

Jim, I didn't post it  !!  that was Lovecraft0 ....
I think this is quite "far" from being commercial just yet, here's my thoughts :

It's not responding well to a single coil pickup yet, there's almost zero "crunch"
It does, however "break up" nice with a Humbucker or two
I think the diodes should be hangin off the second stage, not between, I'd stick
a 10k resistor before the 1M to Q2's source too.
The 5n between stages could well be 10n / 15n plus a roll off cap to ground
before Q2, say 3n3 to 4n7, just to help out with the "piercing" highs a little
otherwise I'm constantly rolling back tone on all guitars.
Try a 47n/100n cap and 1k resistor out of Q2 to the diode pair, with another
roll off cap of say 2n2/3n3 to ground before the 10uf out cap.

I've wired a gain pot of 10k log using a 10uf cap from lug 2 to ground and
grounding lug 1 which seems to work well.

Just some thought's, hope it's useful ?

Marty.

[JimRayden]

Marty, could you please remove it.

Jimbo

Jim, I didn't post it  !!  that was Lovecraft0 ....
I think this is quite "far" from being commercial just yet, here's my thoughts :

It's not responding well to a single coil pickup yet, there's almost zero "crunch"
It does, however "break up" nice with a Humbucker or two
I think the diodes should be hangin off the second stage, not between, I'd stick
a 10k resistor before the 1M to Q2's source too.
The 5n between stages could well be 10n / 15n plus a roll off cap to ground
before Q2, say 3n3 to 4n7, just to help out with the "piercing" highs a little
otherwise I'm constantly rolling back tone on all guitars.
Try a 47n/100n cap and 1k resistor out of Q2 to the diode pair, with another
roll off cap of say 2n2/3n3 to ground before the 10uf out cap.

I've wired a gain pot of 10k log using a 10uf cap from lug 2 to ground and
grounding lug 1 which seems to work well.

Just some thought's, hope it's useful ?

Marty.

Hmm, wierd... I get a really cranked tone with both HB's and SC's... and I tried placing the diodes everywhere, even combine the placements, I still kept coming back to that 2-germs-in-the-middle setting. The diodes in the middle will attentuate the signal, so the second transistor doesn't clip too hard. If I placed the diodes in the end, the transistor would be clipping pretty heavy, along with the diodes. Well I didn't like that, so I put them back in the middle. I guess it's the balance between diode and the second FET clipping that I like. Highs don't seem to pierce either. Anyway, I'm gonna have an audition with it tomorrow, I'll let ears judge, rather than maths.

Oops, sorry for the mixup, you quoted the schematic and I thought it was you posting it.

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Jimbo

[GVC]

Confusion sets in

Jimbo I thought you posted the schemo asking the community for feed back and encouraging people to try it

I don't want to put a wrinkle in any copyright law but is there not a contribtory factor here that you should have made your intentions known in the beginning (ie profit) or Marty should be on the payroll?  I make pedals for me, I am not a manufacturer or EE but in my experience the best ears and players out there have no clue what they are stepping on to get there sounds and if it is worth the price they will pay it!

sincerely- good luck in your endevors, I have been where you are and it is not good.  Heads up and keep building!

Glenn

[JimRayden]

Yes, the original schemo was posted by me, but lovecraft0 made a clearer, digital version of it.

I wasn't going to make it commercial in the beginning but I loved the tone and ran out of money. I think it won't be a big line, not over 10-20 pedals. I'll see where I go from there.

I just want to avoid e-mails like: "you took my design and sold the pedals and now Im gonna sew you and get lotsa mony outta ya!!!!". Next thing you know, you have invitation to court in your mailbox and so on. Such persons DO exist, you know. I know they're not in this forum but they are certainly lurking around. I'll upload it again once I decide so. Hopefully a new, improved version of it.

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Jimbo