Adding volume and tone pots to a Dean Markley transducer?

[Steven D. Wilson]

I have been ask to install a Dean Markley Artist stick-on transducer pickup (inside jack-no internal preamp) in an old acoustic guitar.The guy also wants to add a volume and tone control. My question is will the added resistance of the pots effect the pickup output, and what value pot would I use. I know to use 25K with active systems, but this is not active. Any advice here?

[Paul Verticchio]

Hello Steve.

"My question is will the added resistance of the pots effect the pickup output". Absolutely and not in a productive way.

Your customer will most likely need a preamp for that pup.  I'd suggest an external pre/DI that also has a volume control & EQ.

My personal experience with "bottle cap" style piezo pups is that they all GREATLY benefit from the buffering, active circuitry, impedance matching, gain boost and EQ offered in an outboard preamp.

Another reason (non-technical) I believe the original concept is inadvisable is that most transducer manufacturers now offer add-on tone & volume pots for the specific product.  A cursory look at DM's site shows no such item. 

Best of luck with your project (-:

p.s.: Out of curiosity: what make of gtr is it & where were you/he planning to mount the V&T controls?

[Steven D. Wilson]

Thanks Paul,

You confirmed my suspicions on adding the volume and tone pots. I will advise him against it. I also agree on the need for a preamp with these pickups. The guitar is a rather inexpensive Johnson dreadnaught. He had indicated he would like to have the controls installed along the lower treble bout like a Gibson J160, which of course has a magnetic pickup. I had not yet gotten to the point of seeing what limitations the top bracing may impose on placement. Thanks again for your help!

[Paul Verticchio]

You're welcome Steve.

I just set-up an incoming batch of Johnson dread's last week. For the street price, they're a decent entry level instrument. Definitely not stage grade, but for a little over $100 new, they're a good value. The most basic of setups make them comfortable players.

You may want to suggest a soundhole mag PU to your customer.  Those will easily support the V&T controls he wants. I doubt if two 3/8" holes in the plywood top will impede the sound of that instrument.(;

Have a great one (-:

[Steven D. Wilson]

Hi Paul,

After discussing the options with the guy he has decided to do as you suggested, get a sound hole magnetic pickup and have me install the tone & volume pots as discussed. He hasn't decided on the pickup yet, but I assume I would use 250k pots for a single coil or 500k for a humbucking unit? Thanks again for your suggestions.

[Paul Verticchio]

Steve,

You're correct on the pot value for the volume control.  The tone control can be 250K or 500K; whatever you have handy. 

Best of luck (-: