Bearfoot - Model G  [traced]

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Bearfoot - Model G  [traced]

Postby mmolteratx » 12 Sep 2013, 03:02

Got this one on Monday and traced it today. Really similar to the Honey Bee, but even lower gain with less compression. Not my thing at all.
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Re: Bearfoot Model G

Postby ChargerSG » 12 Sep 2013, 23:04

Looks a lot like the Sweet Honey OD in topology including the "Focus" knob which would be the Model G's "C" control (controlling the negative feedback networks similarly found in the Honey Bee and Model H as well) The additions would be a JFET Inverting stage instead of the Op Amp stage, a Honey Bee Nature Control, and JFET 2N5457 clippers to ground.

http://3.bp.blogspot.com/-UCNpsHI3j7M/U ... ematic.png

Any news on a EGDM schematic ? :)
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Re: Bearfoot Model G

Postby mmolteratx » 12 Sep 2013, 23:37

ChargerSG wrote:Looks a lot like the Sweet Honey OD in topology including the "Focus" knob which would be the Model G's "C" control (controlling the negative feedback networks similarly found in the Honey Bee and Model H as well) The additions would be a JFET Inverting stage instead of the Op Amp stage, a Honey Bee Nature Control, and JFET 2N5457 clippers to ground.

http://3.bp.blogspot.com/-UCNpsHI3j7M/U ... ematic.png

Any news on a EGDM schematic ? :)


It'd be easier to say it's an HBOD with a pot in series with one of the feedback paths, a different taper nature pot and FET clippers. Nothing on the EGDM. I'll draw something up when I get the chance.

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Re: Bearfoot Model G

Postby ChargerSG » 15 Sep 2013, 07:26

mmolteratx wrote:
ChargerSG wrote:Looks a lot like the Sweet Honey OD in topology including the "Focus" knob which would be the Model G's "C" control (controlling the negative feedback networks similarly found in the Honey Bee and Model H as well) The additions would be a JFET Inverting stage instead of the Op Amp stage, a Honey Bee Nature Control, and JFET 2N5457 clippers to ground.

http://3.bp.blogspot.com/-UCNpsHI3j7M/U ... ematic.png

Any news on a EGDM schematic ? :)


It'd be easier to say it's an HBOD with a pot in series with one of the feedback paths, a different taper nature pot and FET clippers. Nothing on the EGDM. I'll draw something up when I get the chance.


It also has the Sweet Honey's smaller 4n7 input cap, and the same 47k/47k voltage dividers.

And okay if you would that'd be awesome!
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Re: Bearfoot Model G

Postby IvIark » 19 Sep 2013, 22:59

Cheers Matt. This is verified

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Re: Bearfoot Model G

Postby trumpetboy » 01 Nov 2013, 13:35

mmolteratx wrote:Got this one on Monday and traced it today. Really similar to the Honey Bee, but even lower gain with less compression. Not my thing at all.


I noticed R14's value is missing. Is R14's value 47k ?

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Re: Bearfoot Model G

Postby mmolteratx » 04 Nov 2013, 08:45

trumpetboy wrote:
mmolteratx wrote:Got this one on Monday and traced it today. Really similar to the Honey Bee, but even lower gain with less compression. Not my thing at all.


I noticed R14's value is missing. Is R14's value 47k ?


Yes, just like the HBOD.

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Re: Bearfoot Model G

Postby drbob1 » 04 Nov 2013, 16:45

I may be out to lunch here, but it looks to me like all the Bearfoot overdrives (and by extension, the BJFE and Mad Professor versions) consist of variations on the basic Rat circuit with a soft clipping circuit in the first op-amp stage and some form of clipping to ground between op amp stages. Then differences in bells and whistles create the slight differences in voicing/response? I've compared quite a few of the Bearfoot versions to each other and actually found them quite useful in general-the HBOD is a brighter, thinner tone that's flattering to some dark guitar/amp combos, like the original Bluesbreaker circuit and the DynaRed/RedHot are very nice takes on the classic Rat voicing.
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Re: Bearfoot Model G

Postby bbkassel » 04 Nov 2013, 21:56

EGDM??
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Re: Bearfoot Model G

Postby drbob1 » 04 Nov 2013, 23:04

To be fair, the EGDM is billed as an overdrive fuzz, and yeah, it's discrete transistors rather than an op amp.
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Re: Bearfoot - Model G

Postby HamishR » 26 Jan 2019, 10:17

Wow - old thread. I built this again just recently and it works perfectly with my set up. I love it! I love that it has minimal compression and it has way more dirt than i need. You should hear it with a Les Paul through a tweed Deluxe - super punchy and a great old-school blues tone. Fab.

The one change I made in the second one i built was to get rid of the C control as it does next to bugger all. I just replaced it with a 27K resistor to make it another 3-knob pedal. Also I like this pedal enough to go out and buy one, and I discovered that my original has 2N5952 trannies in all positions. So the clippers are 2N5952 as well - but of course it doesn't make a huge difference.

If anyone is interested I have drawn up a modified version of IVIark's excellent vero layout with my simple mods. If you are interested in punchy, clear but FAT old-school overdrive this is one of the best I have heard.
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Re: Bearfoot - Model G

Postby HamishR » 14 Feb 2019, 04:56

And after further experimentation I have found that you can replace the Jfet clippers with ordinary old 1N4001 diodes with little change in tone. The feel changes slightly - it's a tad stiffer with the diodes but equally usable - some may even prefer it. I like both. I guess the jfets-as-diodes gives a slightly more "amp-like" sag but it's subtle.

I tried BAT41s because I like how they worked in some other pedals but the volume drop is quite dramatic! The 1N4001 is very close to the original, so might be worth a try for anyone with transistors in short supply. :-)

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Re: Bearfoot - Model G

Postby maoriente » 18 Jun 2019, 03:16

Does the 5k6 drain resistor bias the "3rd" 2n5952 at the typical 4.5v?

I'm limited to using 2n5457 smds, which measure all over the place.
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