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Post by TooManyWires on Jul 3, 2006 23:37:09 GMT -5
Hey, it's been a while since I've been here again, I seem to keep forgetting to check this site often enough. Anyways, I have a question about something I thought I saw on here once upon a time, although, it could well have been long enough ago to be on the GN1 forum. It was instructions on how to turn a cheap RadioShack Piezo Buzzer into a pickup for a guitar. As I recall you had to run it through a preamp, and then you just glued the buzzer to the body of the guitar. I can't remember if you had to modify anything specifically to make it work. Does anyone have this kicking around, or maybe can make something up like that? It'd be for the inside of an electic guitar, most likely. Thanks in advance for the help.
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Post by gumbo on Jul 4, 2006 2:42:56 GMT -5
Hey, yeah!....I remember that...downside was it only worked when you were reversing...
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Post by TooManyWires on Jul 4, 2006 10:18:58 GMT -5
When you were reversing? Whats that mean? Like, you had to have the pickups out of phase or something?
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Post by gumbo on Jul 5, 2006 6:46:02 GMT -5
Sorry TMW, Oz attempt at humour (humor).....like, reversing buzzer on a truck.... :-)
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Post by UnklMickey on Jul 5, 2006 9:31:46 GMT -5
beep........................beep..........................beep........................beep...........................
i guess unk isn't the only one who confuses folks with the suBtle humor.
FWIW, i did get the back-alarm reference, right off.
i didn't discover GN until after the original forum had been hacked.
so, assuming that's where the you originally saw it, i can't help.
i'm fairly certain it wasn't on GN2.
sounds like it could be something the guys at projectguitar might have been into?
it does sound like an interesting idea.
i'm sure the cost of piezo buzzer at "the shack" can't be much.
unk
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Post by Runewalker on Jul 5, 2006 10:27:43 GMT -5
Vague memory here, but something about that piezo recalls a thread discussing sustainer circuits, and the piezo is the feedback occilator. Maybe wrong, but I think that that is where it was raised.
The primary voice on this board for sustainers is 4Real, but have not seen a post from him in a while.
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Post by TooManyWires on Jul 5, 2006 12:56:11 GMT -5
Haha, When it's reversing. Gotcha. I had my head all wrapped up in the technical thoughts already, it seems. Yeah, I don't think it was in relation to sustainers, no. I'm pretty sure it was just a standalone piezo pickup that was made by either modifying or just using a cheap radioshack piezo buzzer. They are quite cheap, I believe like, $4 or $5 will get you one. I've been interested in piezo for a while, but haven't had the cash to spring for a full fledged system, and I just remembered this thread the other day, so I figured it couldn't hurt to ask if anyone else remembered it. Maybe it's just my imagination, or I didn't really understand it at the time and thought it did something that it didn't. I dunno. Maybe someone else remembers it too. I'm not sure if you could just hook the piezo up to a preamp and just let it run backwards, or if you'd need to modify it or something. As I recall you might have had to take it all apart or something.
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Post by wolf on Jul 5, 2006 15:23:12 GMT -5
If I remember correctly, I tried using a piezo buzzer "pickup" long before message boards and the Internet.
Anyway, as has been said, I took apart a Radio Shack buzzer and secured it to a guitar (probably by a screw - therefore do NOT try this with the latest Paul Reed $mith creation).
Anyway, as far as I could tell, it works as a contact tranducer and does not work by sensing the strings as a regular pickup does. In a crude sense, this is smilar to getting a small microphone and securing it face down to a guitar body.
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Post by UnklMickey on Jul 5, 2006 15:42:53 GMT -5
it seems like the reason to take it apart is so you can get direct contact between the element and the guitar body.
it would still work, if left in the plastic casing, but not as well.
the preamp probably isn't needed so much for voltage gain, but more for a low impedance output.
also, piezo elements are naturally hotter on the highs, so some filtering or EQ will be very desirable.
"I took apart a Radio Shack buzzer and secured it to a guitar (probably by a screw - therefore do NOT try this with the latest Paul Reed $mith creation). "
Wolf, what kind of problems would you anticipate there?
unk
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Post by ChrisK on Jul 5, 2006 19:11:33 GMT -5
A piezo transducer will work in this case, unfortunately not well. The transducer senses the differential forces from one side of the device to the other. This means that both sides must have a reference mass attached.
Bodies have varying vibrational movement. Most have sweet spots (a range of frequencies). This also implies dead spots.
Piezo saddle transducers work well since they directly sense the vibrational force variations of the strings at the bridge (where the string harmonic content is the highest) against the mass of the bridge and guitar body (sensing between masses).
In the mid 60's I tried to use a ceramic phono cartridge since I had a ceramic phonograph player (hey a pickup AND an amp). I mounted/soldered the needle directly to the bridge (Tele) and played on (briefly). As I now about the differences between masses (I had the body of the cartridge floating), things might have been better. I should have listened to my father who said that it would not work.
The sound was lousy, the frequency range most narrow, and gee, what did I expect since ceramic phono cartridges make for lousy phonographs anyway.
The typical piezo "buzzer" (it ain't a buzzer but a transducer) has a very high "Q" and hence narrow frequency response (which is why they make excellent self-oscillating designs in a feedback circuit).
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Post by UnklMickey on Jul 5, 2006 20:19:05 GMT -5
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Post by ChrisK on Jul 5, 2006 20:24:36 GMT -5
Well, have fun.
Most piezo pickups are in the saddles (the body mass versus the string vibrational/down tension) or between the body and neck joint (wow, more mass-based differential sensing).
In the saddle position, the piezo crystals are short, narrow, and thick to move the self-response way up in frequency.
In the neck joint position, the thin piezo has the frequency effect of the transducer itself completely swamped by the neck and body masses.
In the land of piezo's, MASS IS!
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Post by TooManyWires on Jul 5, 2006 21:55:20 GMT -5
Yeah, this sounds more like what I was remembering. You had to take apart the buzzer, or use the element or whatever. As I recall it was just a little flat thing about the size of a quarter or so. Then you glued that down to the inside of the body or something. I don't really remember though. The part that had me confused was in thinking that you'd need to have some kind of amp of something. So what the concensus here seems to be is that you could rig it up, and then jsut run the wires straight out as normal pickup wires? Or do some kind of EQ thing first maybe? The saddle pickups would be hard, but since I'm thinking of trying this first in an SG I've got mostly built, the neck pocket would work ok, and if that works out, I'd consider doing it to an old LP copy with a bolt on neck that I love to death too. And since it's a LP it'd be easy to get from the switch cavity to the neck pocket for a wire.
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Post by UnklMickey on Jul 6, 2006 11:49:44 GMT -5
...So what the concensus here seems to be is that you could rig it up, and then jsut run the wires straight out as normal pickup wires? Or do some kind of EQ thing first maybe? .... this is likely to be highly experimental. you should get enough output, but the frequency response probably won't be that wonderful. you might also try sandwiching the element between an extra piece of wood and the control cavity. could be good, could be bad, no guarantees. you'll certainly want to run the output on a separate cable from the pickups, at least to begin with. i seem to remember Falke mentioning piezo elements for some ridiculous price like 3 for a buck. you could buy dozens and experiment with all sorts of ideas on placement and mounting. unk
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Post by TooManyWires on Jul 6, 2006 13:42:01 GMT -5
Hmm, I could just randomly place them all over the place and make like, a pickup web or something like that. That'd be fun to experiment with. I dunno, I'd definately wire it up in a test body until I figured it all out. I've got an old $20 super strat copy thing kicking around that I currently use to test stuff. The issue I'm seeing with that plan is that it has locking trem, and as such a floating bridge, and less sustain, so perhaps the piezo wouldn't work so well. I dunno. Can't hurt to try it, I suppose.
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Post by dunkelfalke on Jul 6, 2006 16:52:16 GMT -5
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Post by quarry on Jul 9, 2006 7:00:11 GMT -5
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Post by TooManyWires on Jul 9, 2006 10:20:21 GMT -5
Awesome link! That looks exactly like what I'm holding in my hands trying to figure out how to get apart. ;D I was totally stumped as to how to get it apart. Then I decided to check the forum here, and there's that link. Muchly appreciated, I'll let yous all know how it goes. EDIT: Well, upon getting my buzzer apart, it doesn't exactly look the same as the one in the pictures. Mine has a little circuit board and three wires coming from the element. So, I think I'll just pick the two that look like the picture there, and use them.
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Post by TooManyWires on Jul 11, 2006 15:34:08 GMT -5
Just a little update here. I got the pickup all built and tested, seems to work fine, but I haven't tried installing it anywhere yet. Since every last one of my guitars currently seems to need its strings changed, and they all also have bolt on necks, I think I'll just loosen the neck up on one of them when I change the strings, and stick the piezo thing in there. The only thing that worries me about putting it there is if it throws off the neck angle and/or intonation or something like that. The other thing I noticed just from holding it up against a guitar and strumming is that I only got sound when I held it up to the neck. I didn't try holding it to the front of the guitar, but I did hold it up to the back, and got no sound from holding it up to the outside of the back of a guitar. I didn't bother to pop off the control cavity backplate or anything, so I'm not sure if or how well it would work there. Also, it didn't sound very bright and acoustic-y and shiny like I expected, it sounded pretty much like a magnetic pickup. But, I'm going to try it in a neck joint or somewhere slightly more permanent before I call judgement upon it.
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