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Old 23rd November 2002, 03:03 PM   #11
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Klaus,

No, cutting Piezos into smaller pieces doesen't destroy them. But you have to solder (or glue) the two wire connections back on the piece you cut out..

Jakob E
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Old 5th December 2002, 12:35 PM   #12
sangram is offline sangram  India
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I had a local guitar tech fix a piezo to one of my acoustics.

I would tend to agree that the sound is bad.

But only in isolation. When mixed with a lot of mic signal, it creates a different feel to the recording. A lot of people use it. LR baggs and fishman make pickups using this material (though the interface system is what makes this kind of pickup viable. Under the saddle they pick up vibrations better than fixed onto the body of the axe...

One accepted way to amplify a grand piano in studio, for example, is to use a few of these piezos for direct and some stategically placed mics. A bit of piezo sound changes the colour of the sound slightly. Notice not for better or worse, just different.

Just another colour on the palette of a musician. And a cheaply available one, at that. You can cut a piezo and make smaller pieces. I use a pair of scissors, but am only able to use the left over piece, with the wires still attached. Helps in cutting out self-resonance...
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Old 10th December 2002, 07:58 PM   #13
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Argghhhhh... piezos in guitars...argghhhhh

For any kind of loud stage use, retro fitted peizos are useless. They pick up handling noise, feed back at the slightest excuse, and are horribly unreliable. I have lost count of the number of times, when I was a guitar tech, that I was blamed for their godawful characteristics! Musos who had beautiful sounding accoustic guitars would get them retro fitted, expecting to get the same tone at stage levels, and it just didn't work at all.

Think of cool calm water... cool calm water.... ahh...

Spleen vented, you can all come out from under the table now
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Old 10th December 2002, 10:43 PM   #14
lohk is offline lohk  Europe
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Nice to hear your complaints about this and that here, pinkmouse, but that is not the point:
I was suggesting piezo discs as a cheap and working input device, something to which you can experiment with, modify, you name it. You can seal it from the backside and construct a god case or housing and fixing.
Then, if you still get feedback problems do not blame the device alone, blame yourself and blame the man behind the mixer too.
Even "good" microphones can sometimes be used as experimental devices, and as a musician I really get fed up with all the "hifi clean sound" approach - making music means creating sound not reproducing it...
What, when I do want to hear and amplify the noise of the fingers on he frets ? Beautiful sounding, pah !

Klaus

ps: And, as far as I know, the "very best sounding" pickups for violins and double basses for example are made with piezo/electret technology
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Old 10th December 2002, 11:23 PM   #15
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Klaus, yes I agree, some of the best pickups do use piezos, I never said that they didn't

Yes, as a musician you shouldn't limit yourself to conventional ways of expressing yourself,and if something different gives you a sound you like, then that's good.

What I am saying is that cheap or diy pickups will not give a realistic reproduction of an accoustic instrument, they have to be designed and built in, especially when used with loud foldback.

An old adage comes to mind here, garbage in, garbage out. If you expect a soundman to do a good job, he/she needs a good stable signal. Every time you have to notch out a problem frequency, you lose a part of the sound of the instrument, and if you have something that's as unstable as a cheap piezo, by the time the feedback problems are sorted, there is nothing left of the origional sound, as well as ruining the gain structure of the mix, and possibly compromising the foldback for other members of the band.

So by all means, create your own pickups, create new sounds and new music, have fun, but be aware of the limitations of the devices
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Old 11th December 2002, 07:54 PM   #16
lohk is offline lohk  Europe
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The Paia Midi Brain uses Piezo discs in the ThumDrum Interface:


http://www.paia.com/midibrn.htm
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Old 11th December 2002, 07:59 PM   #17
lohk is offline lohk  Europe
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Here is the necessary input schematics:
Attached Images
File Type: gif drumsamp.gif (4.3 KB, 415 views)
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Old 11th December 2002, 08:01 PM   #18
lohk is offline lohk  Europe
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inputs:
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File Type: gif drumsens.gif (4.4 KB, 376 views)
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Old 2nd January 2003, 06:07 PM   #19
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I belong to a small Celtic band and do the live sound and recording for them. I am so dissatisfied with microphones I was looking for another options. I, like many of you, did not like the sound of piezo transducers until I ran across a company on the internet call K&K Sound.
http://www.kksound.com/index.html
They have samples of guitar recording, made by their pickups, on their web page, which sound incredible. I didnít really believe them but spent a $100 on their Pure Western system to experiment. I was stunned at the sound! It still lacked, a little, in the low end so we added a preamp which makes our guitar sound gorgeous. Iíll know a lot more after next year playing seasons, but right now it does NOT feed back, at all! Weíve played it right in front of our sound system with no problems.
Next I tried a large transducer in the bodhran, but as Havoc said it has too hot of signal and clipped bad. I used a smaller transducer, 1 - ĹĒ transducer from the Violinissimo pickup, and clamped it between the drum skin and tuning ring. I got a great sound. I must say we are looking for a pure acoustical sound and use nothing more than a little EQ. The band gives me the dirty looks every time I try to add an effect.
Iíve been experimenting with the violin and have not come up with a sound that the band likes, but we are getting close. To answer Pinkmouseís complaint Iíve had the same problem on the violin but by cutting off everything below 80hz Iíve been able to remover the finger noises. I do agree they can be a pain in getting them placed right. The drum and guitar were easy but the violin has been difficult. A mover of just 1/8Ē on the body can change the sound. I am determined to changes the band over to pickups because in live sound, feed back has been a major problem and in recording mic bleed keeps me from picking up the individual instruments.
My question to you guys is I would like to build some small, light weight, high quality buffers to mount at the pickup. This is one I like:
http://www.till.com/articles/PreampCable/
I would like to use a better IC. I would like to use a OPA132 from BB. Do you guys know where I can find more information on bringing down the high impedance of the piezo so that I can run it down a cable without loosing anything? A tube buffer or a transformer looks like the best match but I just donít know enough yet to make a decision.
Thank you,
steve
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Old 2nd January 2003, 08:25 PM   #20
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If you are looking for something for the violin, try getting hold of some PVDF foil. Then, place a piece between the body and the bridge (the wooden piece where the snares run over, between the f-holes). PVDF foil has piezo properties, but is flexible. You could try the same with a small piece of piezo, but the foil is easier.

As for input, a current input should be good. This was used for measurement inputs like for vibration transducers. Protect it very well by clamping with fast diodes to supply rails.
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