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Homemade Piezo


jammy

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I remember seeing a while back a picture of a guitar that had been converted to a piezo output using the piezo thing from a buzzer. I cant find the thread again even after a forum search so Im just wondering if anyone else can? Also, If I were to use a piezo element in my guitar Im guessing I would need some form of pre amp? - if so does anyone have a circuit diagram for one?

Thanks :D

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ok, this is something i've come up with, but i'm unable to try.... u remember de sustainer mod right? if you connect the circuit to the piezo attached to the bridge... is that a fine idea for a sustainer????

right now i think is a genius idea, please, make me see.... XD

:D

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back to the piezo thing, so how about a hooking a circuit up as follows, any thoughts?

peizo elements --> jfet buffer (little bit of boost) --> tone stack (the three band ones used in amps) --> blend pot for combination with magnetic pickups.

-Vadim

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ok, this is something i've come up with, but i'm unable to try.... u remember de sustainer mod right? if you connect the circuit to the piezo attached to the bridge... is that a fine idea for a sustainer????

right now i think is a genius idea, please, make me see.... XD

:D

Actually, that sounds like a great idea! I don't know if it would have enough power to get the string vibrating to sustain the feedback but it would be worth a try.

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i tried this on my strat, but the output was pathetically low!!!, its been a while since i messed with it but i reckon i used the wrong typr of piezo.

i used the 27mm 1.8khz and the 35mm 2.8khz piezos from maplin in the uk

www.maplin.co.uk

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  • 3 weeks later...

definatly possible. I think if you mounted the piezo element on the guitar body (perhaps in a VERY shallow route (0.5mm MAX) then screwed the bridge over the top it would work well, perhaps even put 2 in. Drill some holes from the bridge to the control cavity (or just enlarge the grounding hole) and youll be sorted. :D All you need to make sure is that there is a good connection between the bridge and the elements - to allow the vibrations to be passed on....

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  • 2 years later...

I've installed homemade piezos into two guitars, one with a Floyd Rose and the other a fender style fixed bridge. Heres what you do:

1. Buy piezo buzzer from radioshack, I recomend one with the case about 1" diameter. They are like $3.

2. Pry open the case with a sharp screwdriver. Be careful not to scratch the piezo inside or yank the wires out (they are a bitch to resolder).

3. Now you have the piezo, which is a golden disk about 3/4" diameter, with a thin white ceramic coating on one side, and two wires soldered to it.

4. Take some sharp sissors and cut the piezo in half, one side with both wires, the other with none.

5. Solder 2 wires onto the half with no wires. The hot lead goes to the ceramic coating, the ground goes to the metal. Be careful not to damage the ceramic too much (a scratch or two is ok).

6. You now have two piezos, shaped just right for your guitar.

7. Take some black electrical tape, and cover the side of the piezo with the wires and ceramic. Leave the other side untaped.

Fixed Bridge

7. Take all the saddles off of your bridge.

8. Using a hot glue gun (wait until its REALLY hot), put a dab of glue on one piezo and quickly press it hard onto the treble side of the bridge, out of the way of any holes you may need later.

9. Repeat with the other piezo on the bass size of the bridge. I recommend hot glue because you can always heat it up and remove it later, if you undo the piezo mod.

Floyd Rose

7. Remove the Floyd Rose bridge

8. Using a hot glue gun, place the piezos on the underside of the bridge, in the flat space between the knife edges and the sustain block. Put one nearer the treble side, and the other nearer the bass side.

9. Put the Floyd Rose bridge back in.

You now have your piezo pickups installed. I will leave routing and wiring up to you, as it differs from guitar to guitar.

I will say that piezos have weak lows and strong highs, so I recommend mixing the bass side piezo more prominently. I don't recomend a single piezo, as you will get NO bass.

You WILL need a preamp of some sort, either a buffer or something with gain. Un-preamped piezos sound terrible. I use a low gain (6-10dB) preamp which matches my Seymour Duncans pretty well volume-wise.

Piezos feedback easily when you have amplifiers at high volumes, or any type of fuzz or distortion on the signal. Be careful about things like that, especially with an audience.

Once all is done, piezos have a magical sound. Since they work differently than magnetic pickups, their sound is very different. I would describe it as jangly. I have my Ibanez RG7620 set up to mix my passive Seymour Duncans with the active piezo. With just the piezo on, I would say it sounds like a steel bodied Dobro, VERY tinny. With a 50/50 mix, you can get some great 12 string like sounds. With a 25/75 mix, it sounds like a beautiful accoustic, with deep magnetic pickup low end, and a touch of high end piezo sparkle.

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I opened up a piezo speaker and it had a small circuit with three resistors and a transistor and three wires going to the actual piezo. There are two wires (red and green, both +ves) going to the white ceramic. In the circuit, the green wire comes after the transistor so If I'm lucky it might work if I just ignore the green wire. Any thoughts?

Whatever M, F and G mean anyway.

Love From Samuel.

P.S.

The red and green wires go to different places on the ceramic circle and are isolated from each other. The green wire's area on the ceramic is much smaller than the red's. Black and red makes more sense.

P.P.S.

Black and green, pffft, yeah whatever.

Edited by Samuel McBrian-Brian
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Not sure why this has been bumped forward from three years ago...still

good tips, add some pics and it would make a fine tutorial...

I also experimented with installing these piezos. Piezos work by vibration and so will create a signal from any part of the body that vibrates. The bridge is good but you can get some handling noise (eg from palm muting and such). An even easier way to install them for a slightly different sound is in the neck pocket of a guitar like a strat. Drill a hole through to the neck pickup cavity for the wires and place a shim around it and screw down tight.

Another cheap source of these types of piezo is in those cheap alarm things...open them up and you'll see the same 1" disc. These can often be found in those bargain shops very cheap!

A search of the forums here will yield many successful installs and strategies....

You WILL need a preamp of some sort, either a buffer or something with gain. Un-preamped piezos sound terrible. I use a low gain (6-10dB) preamp which matches my Seymour Duncans pretty well volume-wise.
Got any info on this preamp circuit...that bit is always the tricky part and if you have something at works, please share.

One of the main reasons for the preamp is that the piezo if combined with magnetic pickups will load them down as the impedances are so different, a preamp or buffer avoids this problem...there would also be a vast volume difference.

There are two wires (red and green, both +ves) going to the white ceramic. In the circuit, the green wire comes after the transistor so If I'm lucky it might work if I just ignore the green wire. Any thoughts?

One is probably an earth, or creates some wierd secondary tone...the circuit is an oscillator for some kind of alarm tone I'd guess. The piezo is two plates separated by a ceramic crystal layer. The crystals generate a volatge when they vibrate so you only need two wires, one from each side of the elements. to test it, take two wires and connect to a guitar lead and you should get sound in the amp when touched or struck!

Anyway...piezo's are a cool project and an interesting sound...very different from magnetic pickups, sound best if combined if only a little....they don't really sound "acoustic" but have some of that flavour...and those cheap little buzzers work pretty well all things considered...

pete

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Anyone wanting to get adventurous could also try using 6 piezo elements, one stuck to the bottom or each bridge saddle. I think Cafe Walter used to do a 6-input piezo preamp, and if I remember correctly, he made the design available for public use. He also makes them quite cheaply if you aren't into burning holes in yourself with scorching solder ...

http://www.cafewalter.com/cafewalter/fetpre/index.htm

http://www.cafewalter.com/cafewalter/fetpr...preii_schem.gif is the schematic

Here are a few others

http://www.scotthelmke.com/Mint-box-buffer.html

http://my.execpc.com/0B/CC/fdeck/bass/quickand.htm

http://www.cafewalter.com/cafewalter/piezopre/oppiezobuf.htm

Sorry, couldn't find the 6-1 buffer, but I think it wolud be OK to connect them all in parallel and treat them as one input.

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Ah yes. Some of the piezos radioshack sells make special tones, which is what the extra circuit is for. You should have a piezo with three wires going to it, one wire (ground) goes to the metal disk, the second goes to the larger area of ceramic, and the third goes to a very small area of ceramic. Remove (with a soldering iron) all three wires from the piezo (they are too delicate and short to be of use). Solder one new wire to the metal disk, and the other to the larger area of ceramic. Now you have a standard piezo. You can throw out the small circuit board.

For preamps:

In my guitar, I used a kit preamp, which I do not have with me, so I can't tell you anything about it, besides the fact that it is a FET preamp as opposed to an op-amp preamp. Some people have very strong opinions about which is superior, FET or op-amp, but I am not one of those people.

For building your own preamp, I would suggest using a TL082 chip, because this is sold at Radioshack for $2. It is a dual preamp, so you only need to use one half of it. I would recommend against the 741 chip, which Radioshack also sells, because it is a very poor audio preamp and will likely distort your signal.

One common complaint about the TL082 is that it distorts at relatively low input levels. This should not be an issue as Radioshack piezos put out a very small signal, and you are unlikely to overdrive them. Some (expensive) custom piezos put out much higher voltage signals, and have to be dealt with differently (I heard of someone who built a guitar piezo out of a gas stove pilot lighter piezo that put out 15v audio signals!)

You can search the web for preamp plans, of which there are many. Also, this forum has quite a few suggestions, if you search around. One common FET preamp is the "Fetzer Valve" which I have never built, but is based on a Fender tube preamp (without the tube of course), is very simple, and supposedly sounds great.

I opened up a piezo speaker and it had a small circuit with three resistors and a transistor and three wires going to the actual piezo. There are two wires (red and green, both +ves) going to the white ceramic. In the circuit, the green wire comes after the transistor so If I'm lucky it might work if I just ignore the green wire. Any thoughts?

Whatever M, F and G mean anyway.

Love From Samuel.

P.S.

The red and green wires go to different places on the ceramic circle and are isolated from each other. The green wire's area on the ceramic is much smaller than the red's. Black and red makes more sense.

P.P.S.

Black and green, pffft, yeah whatever.

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Would there be much difference, if any, between these ex-speaker piezos and that transducer you can buy off stewmac? I mean, a piezo is a piezo, right?

Thats a hard question. Obviously special brand name guitar piezos are specialized for audio frequencies. However, I have a hard time justifying the $100 price tag vs. a $2 Radioshack piezo. The audio signal out of a piezo, taken raw, does not sound great. A lot of the expensive piezo sound comes from the expensive preamp and equalizer that comes with it. I personally think the piezo setups I have done on electric guitars sound great. I have done one piezo setup on an accoustic (a friend who only had $20), and in my opinion it was far treble-y.

So I guess the real answer is this:

If you have an accoustic, buy a decent piezo and preamp (NOT PASSIVE!) from Stewmac or someplace else. If you are a real do-it-yourself type of person, and are willing to invest the time and money to build a decent preamp, you can probably get good results out of a homemade system.

If you have an electric, your commercial piezo options are much more limited. There are several piezo fender bridges available, but if you have a Floyd Rose, Tele, PRS style one piece bridge/tailpiece, bass, or any kind of 7 or 8 string guitar, there are NO piezo options. This is where I would recommend doing it yourself. Too much treble is not as much of a problem for an electric guitar, because its built out of a solid hunk of wood. If you know how to solder, installing a piezo in your guitar is a one day job at most, a great weekend project.

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Anyone wanting to get adventurous could also try using 6 piezo elements, one stuck to the bottom or each bridge saddle. I think Cafe Walter used to do a 6-input piezo preamp, and if I remember correctly, he made the design available for public use. He also makes them quite cheaply if you aren't into burning holes in yourself with scorching solder ...

http://www.cafewalter.com/cafewalter/fetpre/index.htm

http://www.cafewalter.com/cafewalter/fetpr...preii_schem.gif is the schematic

Here are a few others

http://www.scotthelmke.com/Mint-box-buffer.html

http://my.execpc.com/0B/CC/fdeck/bass/quickand.htm

http://www.cafewalter.com/cafewalter/piezopre/oppiezobuf.htm

Sorry, couldn't find the 6-1 buffer, but I think it wolud be OK to connect them all in parallel and treat them as one input.

Unless you want to do MIDI or individual string tracking, there is no sound advantage to having 6 piezos over having 2 piezos.

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Unless you want to do MIDI or individual string tracking, there is no sound advantage to having 6 piezos over having 2 piezos.

An interesting point, although Graphtech, ABM, ETS, Floyd Rose and several others might disagree. They all use one piezo element per string. There again, they pick up the vibrations of the strings themselves, not the induced vibrations from the bridge or body. i always fancied the idea of mounting a small transducer under the body end of the fingerboard on my fretless basses so I could adjust the amount of Mwahh that was mixed into the overall sound .. :D

Thanks for the comment and support Jozer.

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