I am wondering if adding a capacitor like an orange drop to a simple piezo circuit will help with the tone? I am working with an antique box, and I wan't to keep it simple. Just a piezo wired to a jack. all volume and tone control coming from the amp.
Will adding a capacitor change the tone from the piezo? make it a little less harsh maybe? I could just try it, but thought i would ask for advice first.
A capacitor is just an electrical spring. The higher the value, the more "springy" it is.
Think of the voltage produced by the piezo as a rough road. A spring is a shock absorber, same as the cap. So what cones out at the other end is smoother.
The capacitor will, depending on its value, reduce the spiky highs. The effect is likely not dramatic to my ear, but it's there. Additionally, the capacitor will somewhat reduce the tendency to feedback. I include a .01 uf capacitor in all my builds.
CB Gitty did a video some time back about this.
Here’s the video, don’t be afraid to experiment
Easy way to mount piezo discs: Lay down a circular bed of hot melt glue, allow to cool, place piezo on top and seal down the edges with more hot-melt. Minimizes extraneous surface noise.
Yes a cap across the jack will help.,.,but dipping the piezo disk in liquid rubber, or encasing it in hot glue, can achieve a similar result.,.,some folks suggest wrapping the piezo in leather.,.,options.,.
Also putting it in series will still be different.
You should make a wire with a piezo, a jack and some alligator clips to do some tests.
You'll be surprised at how much a small or larger cap can change the sound.
I have done the trick with putting a low unit capacitor to the jack as described by Gitty and Glenn. I like the results and it is my preferred method when I use a piezo.
Bottom left ,Orange drop on a piezo rod under the top. You lose some volume but feedback is greatly reduced.
Hi, doesn't lowering the volume normally reduce feedback?
you not really lowering the volume Taffy, your cutting frequencies. So your tone is changing, deferent value caps have different tones which does effect the volume. I have plugger this guitar into a PA and feed back is greatly reduced.
Got ya, so with the cap fitted you can bring the volume up to the same level as before the cap was fitted and not get or get reduced feed back.
It helps to cover the top of the round piezo to cut out feedback. I usually attach the piezo on 2 layers of double sided tape, then put a layer across the top. That kills all feedback in that senario. Hot glue across the top helps too.
Magnetic pickups usually have feedback problems in hollow body/semi-hollow body guitars and most of the time it's related to single coil pickups. The best way I've found to deal with this is to cover the bottom of the pickup and sides under the guitar top with foam attached with electrical tape. This method works every time. Some solid body guitars have had this problem too with single coil pickups and putting foam across the bottom of the cavity will stop the problem in that scenario too.
It's always a good idea to line the inside of your box or hollow areas of your guitar with copper or aluminum tape or cavity shield paint and supply a ground for the tape to combat RF noise that occurs from lighting, electrical circuits, fans, computers, microphones and other components in a stage setting.