DIY Volume Pedal

[liquids]

I've been using a Volume pedal for years, and for about 3 years I've had a Morley.  Live, I use it as a master volume.  I also typically turn it back some to achieve my 'regular' level, as I do some volume swells with delay, and like to have a little 'extra' volume to make up for the lost 'attack' volume when doing such swells, which equals loading, so I prefer surrounding it with buffers if possible.    

The Morley is lame - I had a very old gifted passive string and slider pot Morley Volume pedal for a while.  When I got this current Morley, I assumed it was an upgrade and active, but it's not buffered/is passive (even though it needs power to function).   It's over sized L-to-R compared to most foot sweep pedals.  Jacks are on the sides, to boot.  It has a 'minimum volume' pot on it, which helps, but the sweep still isn't ideal, thought that is the least of all my concerns since I can adjust the pot and my foot action.  I opened it once but due to it being 'optical' so to speak, it's not really usable as a shell. But It works right now and it costs me nothing to keep it, so I've accepted it until I get the cash to replace it or frustrated enough to do so, rather than spend my monthly allowance on other projects.  

Right now, I follow this volume pedal with a very small box with in/out/dc jacks and a buffer, in order to reduce loading from the volume pedal, and to get the signal consistent so it can drive my rack delay without loading (20k input impedance), which is a must, though said buffer box takes up space on my board/two jacks/cables and a spot on the daisy chain.  Ideally, the volume pedal is would be fed a consistently buffered signal which was previously managed with a boss tremolo.  Said tremolo is near replacement, so ideally I need to integrated another buffer in the future (which would take up even more board/jack/cable/DC space I suppose!) to go before it.

Now, For whatever reason, it only firstoccurred to me yesterday that I could build my own volume pedal.  And, to boot,  I could tweak it a bit to my needs for sweep, buffering, etc, to some degree.  But it simultaneously raises a bunch of issues and question, though it seems ideal if I can do all that.

Issue #1) $$!  Smallbear sells the wah shell.  Dunlop Wahs (Vox?) are out there locally at music stores for used process, to be had and gutted.  Either of those options are about $40-50, typically.   Sticker shock was disuasive.  Though I might be able to trade in my Morley toward a Dunlop at the local store....or, if need be, save up for the Smallbear shell.   Other sturdy options?

Issue #2) Space/Mechanics.  Not every pedal (like my Morley) can be simply gutted for various reasons.  Dunlop and Vox wahs are pot-based, granted, but in terms of jacks and such, is gutting the insides and using regular open frame jacks (or any jacks other than these: http://www.smallbearelec.com/Detail.bok?no=770) going to work?   Also, are these shells aluminum?  Can theybe drilled like hammond enclosures?  How hard/hard on your drill bits is it to do so if, for example, if I was interested in re-drilling for jacks 'on the top' rather than on the sides where they usually are?  I'm not sure I know what to expect if I gut a Dunlop shell in terms of the size of the DC jack, which I assume is panel mounted... so I'm assuming the worst, that I'd need to enlarge it if nothing else, to use  a panel mount jack, no?  Also, the Smallbear shell - is it pre-drilled?

Issue #3)  Pots.   I've surfed Smallbear many times, and there's a variety of regular pots, and a variety of wah pots.  My assumption is the volume pot needs to be audio taper, and configured for a lot of rotations.  It's hard to know what part would actually work mechanically, long-term without needing constant replacement.  Smallbear only offers one pot they list as "Pot For Ernie Ball Volume Pedal."  And it's $25 (see issue #1).  Any more info on these pots, or other sources for the kind of variety that will work here, work-arounds, etc?  Is it an option to  get a regular alpha pot and put the treadle assembly on it?  Is that likely to last?  Does pot size matter?

Issue #4) Compatibility.   The beauty of a DIY volume pedal is I can build it so that there is an internal op amp buffer, going to the passive volume control, going to another buffer, all contained within the smaller shell.  This will save me space and one less spot/cable/DC jack occupied on the daisy chain, possibly twofold.   However, since the passive volume pot will be seeing a consistent, buffered signal on both ends, what pot resistance/sweep is best?  For example Ernie Ball suggests that active signals use their volume pot with a 25k pot. Part of me thinks that makes sense, but I'm not certain...and see Issue #2 in regard to said pots.

Last but not least, I realize there may be alternative methods for volume control.  For one I see the OTA-based volume, pedal, the Anderton Volume: http://www.tonepad.com/getFile.asp?id=2  .  On the parts list simply says "Volume Pot."  What taper and resistance is needed - I'm assuming audio?

Input and help is more than appreciated.  

[wavley]

http://www.diyguitarist.com/DIYStompboxes/FX-17.htm

This is what I use and they are pretty cheap too, looks like they fill all of your parameters, I use mine to control my rhythm/lead levels.  There are several people here, including Mr. Marossy, that really seem to like theirs

[JKowalski]

Why not add a buffer to your Morley? The photocell/LED mechanics seem like the most adjustment-friendly type in terms of sweep.

[jkokura]

a good, basic volume shell would be a Bespeco VM-12

http://www.soundslive.co.uk/product~name~Bespeco-VM12~ID~10243.asp

That's the first hit on google. I have one and I'm going to be modding it in the future. Very easy to do stuff, and a much better volume enclosure than a wah enclosure.

I also like my jacks on the top. That's why I dig Ernie ball volume pedals also. This one is a lot smaller (same size as the Boss volume/wah units, the Line 6 expression pedal) and I'd really, really like to know where to get a blank enclosure like it. See if you can find one of those, cause it's easily a better solution than those vox/dunlop enclosures.

Jacob

[liquids]

Why not add a buffer to your Morley? The photocell/LED mechanics seem like the most adjustment-friendly type in terms of sweep.

It's not the easiest thing to do internally.  The board takes up the whole 'lower' inside of the pedal.  Also, it would be a hack job, and I'm not much into that.   That also wasn't the question. 

[liquids]

a good, basic volume shell would be a Bespeco VM-12

http://www.soundslive.co.uk/product~name~Bespeco-VM12~ID~10243.asp

That's the first hit on google. I have one and I'm going to be modding it in the future. Very easy to do stuff, and a much better volume enclosure than a wah enclosure.

I also like my jacks on the top. That's why I dig Ernie ball volume pedals also. This one is a lot smaller (same size as the Boss volume/wah units, the Line 6 expression pedal) and I'd really, really like to know where to get a blank enclosure like it. See if you can find one of those, cause it's easily a better solution than those vox/dunlop enclosures.

Jacob

I could get this sort of enclosure used (probably the roland/boss one, in particular, as well as other semi-similar ones) but it's risky since I've not seen the inside like I have the Dunlop (though not with this in mind), and maybe the Vox, if I ask a friend who has one.   Otherwise, To go to a store and bring a screwdriver to dismantle it, or ask if I can open it up and poke around inside is not usually smiled upon.  I'd expect to hear: "Dude-- it's a wah, we'll just use a power adaptor - Plug it in."  And I'd want to be sure it would all work before I forked out  the money...

Seems like this is not a common project, more Wah builds than Volume pedal builds.  Hmm

[jkokura]

I would say it has room to breath in there. Want me to take some pics and then post them here for you?

My planned mods include:
a dedicated Tuner out
2 opamp buffers (one for the main out, one for the tuner out)
Replacing the volume pot.

My hope is that it will work well both with my electric guitars passive pickups, and my acoustic guitars active one, however, I think that has more to do with the value of the pot, and it's hard to switch between two pots. I'll likely have to go with the stock value of 100k.

There's room in there for that, but it would only take a 15/15 perf board for me to do that. The extra tuner output might be the harder thing to manage. It will probably mean removing the original pcb mount jacks and replacing them, along with the addition of the tuner jack. Right now there's a small PCB for the mounting of the jacks and connecting them to the volume pot.

Jacob

[liquids]

I'm in the US, so after surfing around I'm not sure the Bespeco is something I can actually get around here.  Made in Italy.  Hmm.   So I appreciate the offer for the pics, but I'm thinking that isn't going to work.

Likewise, from further investigation, I was reminded that mechanical wah pedals typically don't utilize the full sweep of a pot.  This would be bad for a volume pedal functioning with a mechanically turned pot wired as a voltage divider.  Strike two...