Dozen Dollar Piezo Pickup Preamp

[Rudy4]

Try saying that three times at a rapid rate.

This is a short video to demonstrate making and using a simple external preamp made from one of the "Sonotone" pickups available from several retailers on Ebay. Yes, they truly were around $12 including shipping.

The Sonotone "pickup" is one of the least liked pickups for acoustic guitar, but a lot of that comes as a result of the coaxial cable piezo undersaddle transducer that normally is supplied with the preamp. The preamp itself isn't all that bad. The only modification done to the pickup is cutting the coaxial pickup off the end of the input cable and soldering a 1/4" jack in its place.

I don't usually use an external preamp with my K&K Pure Mini, but I thought I'd give it a spin with this preamp. I am experimenting with piezo bar-type undersaddles for electric nylon strung short scales I've been making, so this was made expressly for that use.

The video details the preamp construction and then I demo it with my K&K PM equipped acoustic. All of the sound you hear in the demo portion is what's being recorded with the Tascam DR-05 handy recorder placed in front of the Cube EX amp. I have it set to a relatively low volume as I would normally listen to it in the house. (The preamp boosts the level a lot higher than I would normally use it!)

The first part of the video is the guitar straight into the amp and I switch it over to use the preamp, which is easy to see. After I boost the volume up I play a bit with the tone control so you can hear a bit of how it effects the overall sound.

[guitaniac]

Hi Rudy,

I admire your creative skills. Beyond that, I see this experiment as providing some helpful evidence to the folks who may be contemplating replacing a sonitone UST with a Pure Mini. In the case of your nylon stringer, the preamp isn’t being overdriven and the combination of sonitone preamp with Pure Mini transducer works fine.

Taking the PM directly to the amp sounded a little better to me. That may be because your recorder was picking up more live guitar with that lower volume example, or because you can dial in the amp’s tone better. Nevertheless, the dozen dollar preamp would work sufficiently well for plugging into a PA system to get a decently full amplified sound with adjustable tone and volume.

[Marty C]

That’s very cool Rudy. Very creative.

[Rudy4]

Thanks for checking it out.

The guitar being used in the video is a steel strung small body short scale all hog. I did not make any adjustments to the amp or the Tascam DR-05 location, as I wanted to be able to demonstrate the actual change in volume and tone created by the Dozen Dollar preamp. It doesn't get any more quick n' dirty than this!

For those who may be interested, here's the Cube EX settings that were used. This is identical to what I use when using the amp for gigs, with the volume higher, of course.

[Rudy4]

Originally Posted by guitaniac

Hi Rudy,

I admire your creative skills. Beyond that, I see this experiment as providing some helpful evidence to the folks who may be contemplating replacing a sonitone UST with a Pure Mini. In the case of your nylon stringer, the preamp isn’t being overdriven and the combination of sonitone preamp with Pure Mini transducer works fine.

Taking the PM directly to the amp sounded a little better to me. That may be because your recorder was picking up more live guitar with that lower volume example, or because you can dial in the amp’s tone better. Nevertheless, the dozen dollar preamp would work sufficiently well for plugging into a PA system to get a decently full amplified sound with adjustable tone and volume.

Yes, this does demonstrate that a K&K Pure Mini could be substituted directly for the actual undersaddle transducer that is provided in the Sonotone pickup equipped guitars.

The sound quality may seem a bit shaggy when the preamp is used, but that might be a result of how much the volume level increases. The recorder input level was not adjusted, so the recorded level may be a bit overdriven. In use it's actually a pretty clean boost.

[jricc]

Pretty cool use of a Sonitone preamp. I admire your woodworking skills. I'm not equipped to do that, skill wise or tool wise.
I wish I was as I have an unused Sonitone preamp/pickup lying around.

[martingitdave]

Sounds good. More than one way to skin a cat for $12!

[guitaniac]

Oops! I thought it was the little nylon stringer that you referred to in another recent thread. I must have got that impression from the slotted headstock. I should have realized that you wouldn’t be bending notes so easily on a nylon stringer.

[fedexnman]

@Rudy4 I have a cube 30x and it sounds great with a K&K guitar , same settings . It blows my mind when I use an acoustic amp and how much mids and bass , I have to cut to get it to sound good , but if I just plugin to the cube 30x it's sounds really good .

[Rudy4]

Anyone who wants to duplicate this preamp can find the full size printable pdf HERE.

I'm having fun with using it, and it might be a good option for anyone who has a guitar equipped with a passive piezo-based pick up. I normally use my K&K Pure Mini equipped acoustic without a pre, but it does sound better with one. I used to have a Behringer ADI-21 but gave it to a friend in need. The ADI-21 is another good low buck option for those who want to try a pre for their passive pickup-equipped guitar.