Can anyone tell me definitively if the SIZE of the piezo disks used makes a difference? I have read some who say it doesn't matter much, and I accidentally ordered some pretty small disks, so I'm wondering...
Also, can someone tell me how piezo RODS differ from disks?
I'll also comment: I get the best results, where piezo disks are concerned, when I instal two disks together, instead of just one. Anyone else agree?
Replies
Looking at the technical specs, a piezo is a high impedance component and most amplifiers require lower impedance to reproduce the sound accurately. By wiring in parallel the impedance is cut in half, and works better with the amp. If wired in series, the impedance doubles and performance falls.
A disk and a rod piezo are very similar in that they both turn vibration into an electrical signal. They differ in that a disk can read the vibration by contact, and a rod requires pressure. For example, a rod will not work if it is merely taped to the box. A rod piezo works best when it is installed in a bridge and in direct contact with the saddle - which is under pressure from the downward force of string tension.
Most rods I've seen have a very small jack plug, not ¼", and are made to be plugged into a preamp. Simply cut and strip the wires and solder to the jack. There is no true positive and negative orientation. However, if wiring 2 in parallel, make sure you treat the same wires as pos and neg.
Do you feel the rod piezo sounds better than the disks? I used disks on my first build, and a rod on second. They sound about he same to me (could be my being new to playing/building), both good, but not too much difference. Yet I have read that the rods are better. I find the disks easier to install, as it was a pain to cut the perfect slot for the rod to rest in... thoughts? Also, too keep with the 'bolt' retro feel but get a good flat bridge, I grind down a bolt/screw in half so it sits flat...works on all styles of piezos and I find the wood threads gives some extra room for strings to sit in and not lay across the top of a sharp thread (especially if you angle the bridge, which is the opposite way of the angle of threads on standard threaded screws.)
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I've found no real noticeable difference, even with a small piece cut from a disk. Read more here. <--- Click that
Yes, 2 piezos (even 2 half ones) wired together IN PARALLEL give a better response
Another vote for 2 in parallel, its the way I wire mine, they just sound better to me than one.
Just curious, why would it make 2 sound better? Would it be like a "stereo" effect? I also have been looking into the piezo rods, some of the better prices on ebay they seem to already have a 1/4" jack on them. So I guess just cut off the jack and wire as normal? How would you know if the wireing is correct to the input jack terminals or does it matter.
Thanks for any response.
RKIII