extra knob on volume pedal

Bobby Burns · From: Tennessee, USA

I have an old Goodrich pot pedal. Any model number marking has been worn off long ago. It has an extra pot with a knob on it down by the in/out jacks. What is this supposed to do? I'm not sure it is doing anything now. Was it a tone control originally? Maybe a taper control? Does anyone have a schematic, if I decide to rewire it. I am going to be putting a new volume pot in it anyway, so I thought maybe I would rewire the original circuit. Is this a bad idea? Should I just put a pot in it and make sure that nothing additional is in the signal path?

Jack Stoner · From: Kansas City, MO

Sounds like it may have had the "Myrick" mod installed.

Lee Baucum · From: McAllen, Texas (Extreme South) The Final Frontier

Some of the real early Goodrich pedals had a big knob on the side, that you could roll with the toe of your shoe. As I recall, it was a tone control of some sort. I think they had a "Curly Chalker" model with a big knob like that.

Richard Sinkler · From: aka: Rusty Strings -- Missoula, Montana

I had (have) one of the ones with the big wheel. Model 6122. My understanding is that it had a matchbox circuit installed and the knob had the same function (tone control?) as the early matchboxes that only had one control (maybe later generations still only have one control - don't know - I quit using a matchbox) I had to buy this pedal in an emergency. My pot in my pedal went bad and the only store here in the Bay Area that sold steel guitar stuff didn't have a pot and this was the only pedal they had. I was already using a matchbox at the time and this was redundant. I removed the circuit board and pot from the pedal as it was far more convenient to have the control clipped to the leg of the guitar.

I don't know what this "Myrick mod" is, but chances are you just have the 6122 with the built in matchbox. Does it need a 9v battery?
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Carter D10 8p/8k, Dekley S10 3p/4k C6 setup,Regal RD40 Dobro, Recording King Professional Dobro, NV400, NV112,Ibanez Gio guitar, Epiphone SG Special (open D slide guitar) . Playing for 55 years and still counting.

Bobby Burns · From: Tennessee, USA

Thanks for the replies. I don't think mine ever had a circuit board, but it does have a big knob.

Dean Parks · From: Sherman Oaks, California, USA

I thought that knob changes the taper.

Don Sulesky · From: Citrus County, FL, Orig. from MA & NH

I still have my 1622 Goodrich pedal.
I keep it around just as a spare.
What I did do though when I was using it was remove the tone control knob and wire in another jack so I could connect my tuner to it and I used a wal-wart to power it in place of the 9v battery.
Don

Tim Kowalski · From: Illinois, USA

Mine is a tone knob.
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Bobby Burns · From: Tennessee, USA

So what is the advantage of a taper control? What does it do?

John Groover McDuffie · From: LA California, USA

Actually the Goodrich model 122 (6122?) has a taper control, which incidentally does have an effect on the tone if you aren't using a buffer before the pedal. The taper control adjusts how fast the volume comes up relative to the pedal travel. You can hear the difference if you place the pedal midway in it's travel and rotate the taper control.

I like having the taper control so much that I added it to my two other Goodrich pedals, added one to a Sho-Bud pedal at one time, and converted the minimun volume knob on a Boss FV200 to a taper control.

I have a schematic which I will scan and post later.

Bobby Burns · From: Tennessee, USA

Thanks John. I look forward to seeing the schematic.

Richard Sinkler · From: aka: Rusty Strings -- Missoula, Montana

It could have been a taper control, I didn't use it enough to see exactly what it was. Just noticed that it changed my tone when moved from one end to the other.
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Carter D10 8p/8k, Dekley S10 3p/4k C6 setup,Regal RD40 Dobro, Recording King Professional Dobro, NV400, NV112,Ibanez Gio guitar, Epiphone SG Special (open D slide guitar) . Playing for 55 years and still counting.

Bobby Burns · From: Tennessee, USA

Still interested in seeing this schematic.

Bobby Burns · From: Tennessee, USA

I'd still like to see a schematic of the taper control if anybody has it.
Thanks.

Richard Sinkler · From: aka: Rusty Strings -- Missoula, Montana

Bobby, why don't you try to email John directly. He may no longer be reading this post.
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Carter D10 8p/8k, Dekley S10 3p/4k C6 setup,Regal RD40 Dobro, Recording King Professional Dobro, NV400, NV112,Ibanez Gio guitar, Epiphone SG Special (open D slide guitar) . Playing for 55 years and still counting.

Eric Philippsen · From: Central Florida USA

The 6122 was the first VP I ever bought when I started playing steel guitar a long time ago. I bought it new and it was available with either a tone control or a taper control.

Michael Lee Allen · From: Portage Park / Irving Park, Chicago, Illinois

REMOVED
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"Wisdom does not always come with age. Many times age arrives alone."

Michael Lee Allen · From: Portage Park / Irving Park, Chicago, Illinois

REMOVED
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"Wisdom does not always come with age. Many times age arrives alone."

Richard Sinkler · From: aka: Rusty Strings -- Missoula, Montana

Great info, but none of those are the model I have. It clearly states "model 6122" on the bottom plate. It had the Tone (or taper) wheel, a circuit board, and a 9v battery inside. It does not have a power cord or even a jack for an AC adapter. So, I think there is at least one more model with the wheel not shown here. It could be that the model 126 above was renamed 6122 (or vice versa) but the ad doesn't mention anything about the circuit inside. I am almost positive that when I bought mine, it was in the manual that it had a built-in matchbox and the control was for tone (I think technically, it was for matching impedance to the pickup as the current buffer amps do.
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Carter D10 8p/8k, Dekley S10 3p/4k C6 setup,Regal RD40 Dobro, Recording King Professional Dobro, NV400, NV112,Ibanez Gio guitar, Epiphone SG Special (open D slide guitar) . Playing for 55 years and still counting.

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