Linear vs audio taper pots for volume pedal

Rick Contino · From: Brattleboro, Vermont

For most of my steelin' days I've used an old D'Armond volume pedal, but have recently been trying to switch over to a goodrich. I outfitted it with a Tom Bradshaw pot and can't seem to get used to how quickly it gets too loud in the sweep. I'm thinking this might be because the Brasdhaw pot is audio taper and I'm used to linear? Anyone out there have any thoughts? Are there any Bradshaw-quality linear volume pots to be had?
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Shobud "The Professional" D-10, Stage One S-10, National "New Yorker," NV400

Steve Collins · From: Alaska, USA

You have it correct. Used in volume situations audio taper is the smoother-sounding of the two taper shapes. If audio taper sounds abrupt to you, linear would sound far worse. Make sure you have the wiper wired correctly and you have the input/output going to the right places. If it is wired incorrectly it is possible to get volume swells, just not the ones you want.

Steve Collins · From: Alaska, USA

Also, it is not unheard of to have a linear pot labeled as an audio pot, as the codes were switched a few years back. Check it with a DMM to be sure it is audio taper.

Rick Contino · From: Brattleboro, Vermont

Interesting, Steve. I thought a linear taper pot has a more "linear," or consistent swell as the volume went up and that an audio taper was quicker to increase at the beginning and then levels off. This could be mere speculation though. I'm also speculating that the pot in my D'Armond is linear. I can't see how to get the thing apart without breaking it, which is one reason I'm trying to use a goodrich.

I could have wire the pot incorrectly, but it works as it should on the whole. I would think there would be a more obvious problem if wires were going to the wrong places. There is nothing drastically wrong with how it works. I just have a harder time hitting the sweet spot in the sweep. I thought practice would remedy this, but its been 6 months I've been using this VP exclusively.
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Shobud "The Professional" D-10, Stage One S-10, National "New Yorker," NV400

Jack Stoner · From: Kansas City, MO

An audio taper pot (there are several audio tapers) generally increases volume the way the ear senses it. Audio taper pots are the standard for Pedal Steel Guitar volume pedals.

Linear pots are just that and are more used to control voltages, etc in circuits.

Dave Grafe · From: Hudson River Valley NY

As Jack has correctly noted, human hearing is logarithmic in response, thus a logartihmic "audio" taper pot is generally used in volume control applications. Some folks here on the forum have said that they prefer the linear, however, so to each their own...

Rick Contino · From: Brattleboro, Vermont

Thanks for the responses guys. I guess I'll stick with it and hope practice makes the goodrich VP easier to manage.
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Shobud "The Professional" D-10, Stage One S-10, National "New Yorker," NV400

Tom Bradshaw · From: Walnut Creek, California, USA

Rick: I think the Dunlop pot you bought from me is defective. It does have an audio taper (or should have), with a smooth progression of the volume from full "off" to full "on". Since you indicate that it provides volume very quickly, then tapers off, that shouldn't happen. Therefore, I'm sending you another pot and ask you to replace the pot (and I'm sorry for this) I sent you.

I stand behind everything I sell. If you would have notified me of the problem, a replacement pot would have been in the mail to you promptly. ...Tom

Rick Contino · From: Brattleboro, Vermont

Wow, I hadn't considered that the pot might be defective. Thank you for the proactive service!
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Shobud "The Professional" D-10, Stage One S-10, National "New Yorker," NV400

Donny Hinson · From: Glen Burnie, Md. U.S.A.

An audio taper pot installed backwards exhibits just the reverse of what is intended, the sweep comes on very fast initially, and the last two-thirds of the rotation does virtually nothing.

Rick Contino · From: Brattleboro, Vermont

By "installed backwards" do you mean wired incorrectly? I would think reversing the wiring would give me the Jerry Byrd-style of forward lowering the volume and back increasing it.
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Shobud "The Professional" D-10, Stage One S-10, National "New Yorker," NV400

Blake Hawkins · From: Florida

Rick, What Donny said is correct. Because of the log taper you can't just reverse the wiring.

Two ways to get Jerry Byrd method:

Obtain and install a pot with "reverse log" taper.

Or just wind the string around the other way so that
the pot runs backwards.

I don't know how Jerry did it, but I'm sure someone
on the Forum knows.

Blake

Marco Schouten · From: Amsterdam, The Netherlands

My guess is the wiring is soldered incorrect.
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JCH SD-10 with BL XR-16 pickup, Sho-Bud Volume Pedal, Evidence Audio Lyric HG cables, Quilter Steelaire combo

Rick Contino · From: Brattleboro, Vermont

Interesting. I'm almost positive that I have the wires going to the correct locations. I studied Greg Cutshaw's pictures pretty intensively. I am a novice at this though, so its entirely possible that my solder joints are less than perfect. I'll try re-soldering this weekend.

Trouble is that it is such a subtle problem. I don't think I could even detect it practicing at home. Its only in live situations where I'm playing at stage volume that I have a hard time keeping the volume reigned-in.
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Shobud "The Professional" D-10, Stage One S-10, National "New Yorker," NV400

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