FORUM

Please have a look at our Forum Rules. Lets keep this forum an enjoyable place to visit.

A A A
Avatar

Please consider registering
guest

sp_LogInOut Log In sp_Registration Register

Register | Lost password?
Advanced Search

— Forum Scope —






— Match —





— Forum Options —





Minimum search word length is 3 characters - maximum search word length is 84 characters

No permission to create posts
sp_Feed Topic RSS sp_TopicIcon
How to make your own piezo violin pickup for about 2$ (or less)
Topic Rating: 5 Topic Rating: 5 Topic Rating: 5 Topic Rating: 5 Topic Rating: 5 Topic Rating: 5 (2 votes) 
Avatar
DanielB
Regulars

Members
September 3, 2012 - 1:54 am
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline

Ok, since some folks here occasionally comment on how long my posts are when talking about a technical matter, I am going to break this down into shorter posts to explain the steps.  Hopefully that keeps everyone happy who has an interest in this topic.  wink

 

Piezo pickups for violin are fairly popular and they can be bought in many places.  Some of them don't cost a lot, either.  But I think that we can beat the lowest price anyone is likely to find by making one.  My electric violin has one, of course, but that is the only one that I actually ever bought.  I usually have made my own any time I needed one.

As stated in the topic, you can make your own for about 2$ (or maybe even less).  It isn't hard, and there's really only 2 pairs of wires to hook together. 

But first off you need the parts.  If you go to your local dollar store (or similar cheap place) you can probably find the items pictured.  One is a little mic and earphone for use with computer to do things like online audio chats, the other is a little door/window alarm.  Both were bought at a dollar store and yup, cost 1$ each.

100_0288.JPGImage Enlarger

sp_PlupAttachments Attachments

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
DanielB
Regulars

Members
September 3, 2012 - 2:31 am
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline

We'll start with the little alarm.  Take it out of the package (might want to save the batteries, if you have anything like a laser pointer or something they'd fit) and take it apart.  Sometimes there's a little screw, but this particular type is just snapped together and you can carefully pry the back off it with a screwdriver.  It will look something like this:

100_0290.JPGImage Enlarger

If you lift up the circuit board, you'll see a sort of metal disk thing.  Cut the wires on it off, leaving them as long as you can.

100_0291.JPGImage Enlarger

Ok, now it is time to get destructive!  LOL  Use a pair of pliers and carefully break away the plastic until the metal disk comes loose.  It isn't *super* fragile, but try to avoid bending it too much or denting the crap out of it.  When you have that out, you can carefully scrape off any excess glue around the outer edge with a knife.

100_0292.JPGImage Enlarger 

That, ladies and gentlemen, is the piezo element.  All we need to do now is provide a way to hook it up to your computer (or other sound device like a guitar amp or whatever).

By the way, you may have seen something that looks just like that in some other place, like a musical greeting card or a small toy that has sound effects built into it.  Those usually will work too, and if you happen to have one lying around, it can bring the price of this project down to even less than 2$!

sp_PlupAttachments Attachments

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
DanielB
Regulars

Members
September 3, 2012 - 3:32 am
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline

Ok, this next part is where some folks will get worried, because it deals a bit with wires and such.  But it is easier to do than it is to write or read about.

First thing you need to do is take the computer earpiece/microphone thing, and cut the wire as close to the earpiece/mic part as you can.  That's to give as much cord as possible later when you actually go to use the pickup.

Now you need to strip off the black rubber/vinyl from about an inch of the end you just cut.  The covering/coating on mine was wimpy enough that I just dug a thumbnail into it and pulled of a bit.  Yours might be a bit tougher, in which case you can carefully use a knife to cut the coating just a *little* to let you pull it off.  Try not to go deep enough to cut into the metal wires inside.  It doesn't usually take much of a cut.  And then you'll see something like this..

100_0293.JPGImage Enlarger

Ok, at this point panic might set in for some people.. 4 wires of different colors and you don't know what any of them do.  Just relax and take a deep breath, though.  If you have the same sort of earpiece as I had, then I'll tell you exactly which wires you need to use.  If not, then explain or post a pic of what you do have and we'll see if we can help you figure it out.  All will be well.  LOL

The only ones you actually need in this case are the red one and the one that looks like bare copper.  They have a sort of vinyl or whatever coating we have to take off  little of though.  The easiest way to do that is to just burn it off the very ends of the wires ( a few mm) with a lighter or match.  Then either scrape the burnt bit gently with a knife or with a little sandpaper so you can see bare copper near the ends when you look close.

The other wires can just be trimmed off short so they don't get in the way.

Then you take your piezo element (the disk with the two wires) and twist one of the wires on the disk to the bare looking wire on the cord and plug.. and the other wire from the disk to the red wire on the cord and plug.   Then use a little tape or something to make sure the bare metal on the wires doesn't touch the bare metal on the other wires.  I used a bit of hotglue.  I also hot-glued the ends of the wires we aren't using, just to make sure they didn't touch stuff and make noise or anything.

100_0294.JPGImage Enlarger

And next, you uh... uhh..

Well, actually, we are done!   If you do all these steps you are now the proud owner (and maker) of a piezo pickup!

Next I'll put this weird looking little contraption on my acoustic violin and well see what it sounds like.

sp_PlupAttachments Attachments

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
DanielB
Regulars

Members
September 3, 2012 - 4:55 am
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline

Couldn't find any poster putty, so I ended up just sticking it on with a little piece of beewax.

100_0298.JPGImage Enlarger

I didn't play around with placement, just sort of stuck it on somewhere near where I've seen piezos attached to acoustic in some pics.

Well, it makes a sound..

Not the sort of sound I'd usually like, but moving it to different spot on the violin, even moving it less than an inch could fix that.  Every spot on the top of an acoustic violin vibrates favoring different frequency ranges, and some experimentation would probably find a sound I find more pleasant.

I already have an electric, and don't have much interest myself in "electrifying" my acoustic, so I'm not likely to mess with it much. 

But if one didn't have an electric or a pickup, maybe not a good microphone or perhaps didn't have a microphone at all?  This could be a very workable starting place.  A bit of playing around with trying different spots on the violin to find the sound one likes best, and then either the EQ on  a guitar amp or PA system or in recording software.. Some noise reduction to take out the hum, maybe some reverb or other effects, and it could get a very usable sound for at least beginning with some recording or making a track to get in on the group projects here on Fiddlerman.com

For all that it was cheap and home-made, it works.  With some messing around, it would work better. 

sp_PlupAttachments Attachments

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
ozmous
Honorary advisor
Members

Regulars
September 3, 2012 - 5:55 am
Member Since: July 8, 2012
Forum Posts: 328
sp_UserOfflineSmall Offline

yes! that's fantastic, i will try to make one so that i can record sounds properly :)

but, that is (i think) only good for computers and other amplified speakers.......

but if you want a complete, simple, amplified speaker for that(i.e if you don't want to record sounds, you just want to make it loud, like electric violins), you'll only need two npn transistors, caps and resistors, here's a schematics:

just connect the output to the speaker and the other wire of the speaker to ground, and that should be it :) oh, and btw, you can also find piezo transducers on digital wristwatches, that's where i get mine :)

cheers! - ⁰ℨ

Avatar
Kevin M.
Nicholson, Pa
Members

Regulars
September 3, 2012 - 11:20 am
Member Since: September 10, 2011
Forum Posts: 1957
sp_UserOfflineSmall Offline

Thank you Daniel,  I saw something simalar to yours but they used a smaller piezo from a greeting card and attached it to the bridge.

 

http://www.bluestemstrings.com.....geEV1.html

Avatar
DanielB
Regulars

Members
September 3, 2012 - 2:36 pm
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline

There are a LOT of ways this could be improved.  What I was doing here was showing an easy and cheap way to get started with piezo pickups for recording or if someone just wants to try electrifying their acoustic.  It's just a starting point.  Something easy-peasey and cheap as dirt in case somebody wanted to record their violin and had no sort of microphone or pickup at all.  

The sound sample I recorded of it has a bit of hum and is to my ears quite tinny.  But i could take it into something like Audacity and use noise elimination for kill the hum and tinker with the eq and maybe add a bit of effects and get something I could use as a reasonable recording.  For a couple of bucks, that's an ok place to start. 

 

@ozmous: Absolutely, Oz.  With a little circuitry, these can actually sound quite good.  Just used bare like I have shown, the impedance match between the very high impedance piezo element and the input of a computer soundcard isn't very good, which is why it sounds so tinny. 

I prefer to use an FET with piezos instead of a standard small signal transistor, at least at the first stage.  But your circuit is like what a lot of electrics use for the headphone amp that is built in.  I haven't tried building itm but it looks like it should work.

 

@kevin: I didn't want to mess around with figuring an attachment to the bridge for a quick demo project like this, but it very possibly could give better sound.  And as both you and Oz noted, piezos come in different sizes and smaller could be nice.  This was just something crude and simple that could be toggled together in less than an evening without having to order parts from an electronic supplier or scrounge around for parts.  But yeah, use a piezo out of an old greeting card that is kicking around the house and use the cord and plug off an old set of earbuds or something, and it wouldn't even take a trip to the dollar store.

A bit of copper foil (or any of several other options) to make some shielding to cut down on the hum would be an easy upgrade.  Use something like an old wooden black checker to "cover up the ugly", and it could even start to look better.

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
Fiddlerman
Fort Lauderdale
September 4, 2012 - 4:55 pm
Member Since: September 26, 2010
Forum Posts: 11717

And if you guys give up, visit FiddlerShop for the finished product. LOL

"The richest person is not the one who has the most,
but the one who needs the least."

Avatar
razor02097
Member
Members
September 7, 2012 - 8:38 am
Member Since: August 27, 2012
Forum Posts: 11
sp_UserOfflineSmall Offline

I made one from the parts bin and it works!  The problem is it will take quite a filtering circuit to make it sound good.  I tried an experiment and hooked up my $10 Korg tuning clip to the amplifier.  It actually sounded much much better than the home made one.  However when I added it to my effects pedal and turned up the distortion I realized it started to sound like a harmonica duncecap

Avatar
DanielB
Regulars

Members
September 7, 2012 - 8:51 am
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline
10sp_Permalink sp_Print
0

With piezos in general, most of them will sound much better with a pre-amp and some tone shaping circuitry. 

But if you don't have that, using the noise reduction and EQ in some recording software like Audacity would allow a crude little pickup like this to at least end up providing a usable recording. 

For running into an amp or through effects for a live sound, I'd want at least a simple pre-amp circuit on it to get a better match of the impedance and level for an amplifier's inputs.

On the other hand, if this little 2$ rig was all one had, it can at least be workable for recording a violin with.  Might actually get a better sound using the microphone on the earpiece, as per the other thread.  But this is a cheap entry to being able to try a piezo.

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
RosinedUp
Honorary tenured advisor
Members

Regulars
September 17, 2012 - 12:33 am
Member Since: September 7, 2012
Forum Posts: 985
sp_UserOfflineSmall Offline
11sp_Permalink sp_Print
0

I wonder what would happen if somebody used four little transducers glued to the bridge, one for each string, and wired each with its own amplifier and speaker.  Then the circuits could be equalized.  I'm guessing that it's for more than one reason a silly idea, but I wonder if it's ever worked for anybody.

Avatar
DanielB
Regulars

Members
September 17, 2012 - 1:45 am
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline
12sp_Permalink sp_Print
0

It is not all that silly an idea.  Some "stereo" pickups use a transducer under each bridge foot.  The sound is going to be a bit different under each foot and by directing them to different channels (basically a separate amp or amp channel and speaker for each).

There been guitar pickups designed with 6 or more different coils to pick up each separate string and run them into a mixer so they can each be eq-ed and a mix can be made of them.  So the principle has been thought of and tried at least somewhat.

But none of those sorts of ideas ever really took off huge with enough players to get enough market to become a standard option.  Multiple amps or even a stereo amp for performance amounts to more expense, more time to set up, and more that can go wrong.  Also a mountain of gear can distract from the performer or be a pain to actually run at a live performance. 

It is not a silly idea though, RosinedUp.  The only drawback I can think of immediately to putting 4 transducers on the bridge would be that the added mass could change and damp the sound of the instrument somewhat.  But very small ones, and some clever mounting, and I'd bet it could be done and still sound good.

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
Ferret
Byron Bay Australia
Members

Regulars
October 18, 2012 - 8:41 pm
Member Since: April 22, 2012
Forum Posts: 1575
sp_UserOfflineSmall Offline
13sp_Permalink sp_Print
0

Fiddlerman said

And if you guys give up, visit FiddlerShop for the finished product. LOL

True. I did. It saves a lot of mucking around blink

Seen it all. Done it all. Can't remember most of dunno ..... What was I saying???? facepalm

Avatar
DanielB
Regulars

Members
October 19, 2012 - 3:05 am
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline
14sp_Permalink sp_Print
0

Nothing at all wrong with that, either, Ferret.

While a few brave soul may try the route of cobbling their own together, I think that most people would prefer a nice pre-made unit.  This was more a demonstration of what can be done for a couple of bucks, with no real electronics or soldering. 

Honestly, I don't feel the sound quality of the 2$ piezo explained here is what I would want for recording.  But it would be better than nothing for someone who couldn't afford more and it might actually have some neat sounds through guitar effects boxes, if someone had just been dying to try that.  But even the primitive form explained here could work for recording, with a bit of noise reduction and tweaking the tone with the equalizer available in Audacity.

Myself, I would use maybe 5 more parts and solder together a particular type of preamp to go with the homebrew piezo, and that can actually sound pretty good.  But not everyone has soldering gear or experience with building even simple circuits. 

For someone just looking to record, the 1$ condenser mic in the other thread sounds better to me for contenders in the "extreme budget" range and is less work/cobbling.  And for someone who definitely wants a piezo pickup with much less fuss, Fiddlerman has some nice options available over in the Fiddleshop. 

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
Fiddlerman
Fort Lauderdale
October 20, 2012 - 2:22 pm
Member Since: September 26, 2010
Forum Posts: 11717
15sp_Permalink sp_Print
0

The latest one that I'm testing is "The Realist" transducer. That is a nice piezo pick-up and doesn't affect the sound much when left on the instrument either.

"The richest person is not the one who has the most,
but the one who needs the least."

Avatar
silver
New member
Members
November 17, 2012 - 7:07 pm
Member Since: November 17, 2012
Forum Posts: 2
sp_UserOfflineSmall Offline

Daniel B,

I like your idea of soldering together a couple of these piezo pickups, and adding an preamp also.  I admit that I am new to electric violins so my knowledge is limited so please excuse me if I say something that's completely wrong.  I was wondering what inexpensive preamps you would recommend for volume and tone control or if I should just use ozmous' schematic. I don't want the pickup to be seen, so could I put all of this under the bridge in the body of an electric violin? Any advice would be helpful.

Avatar
Tyberius
Members

Regulars
November 17, 2012 - 8:36 pm
Member Since: November 8, 2012
Forum Posts: 555
sp_UserOfflineSmall Offline
17sp_Permalink sp_Print
0

Audio circuits need impedance matching as Daniel has covered. A problem with using standard NPN transister is the distortion you get when you start to drive it for extreme range and harmonic audio. Its fine for single precise tones, but you are going to have issues at any amplification or if you stage the gain. It would be like an AM radio - dull, flat and lifeless at best. The clipping and clamping will distort your input. That is, whatever isn't lost in the trasnfer to the transducer and RF integrated at your solder "antenna". The cable needs to be grounded and shielded from the transducer to the jack or any outside signals will be induced into the circuit. It really needs staged filter with bandpass cutoffs. You also need offset limiters so you don't blow the amplifier with internal feed back and eddy currents. Field effect transistors work great for sensing cirucits, but you do need to understand what they are doing and how to set your limits.

An OP amp IC would do alot of the filtering internally with zener diodes as limiters. A good hobbyist op amp IC is the 741. Really simplistic in its operation and hookup for most people that can use a soldering iron (not with cold solder joints)

Remember if you do use a separate power suppy for your project, tie the grounds together. Floating grounds tend to seek the lower of the 2 with not so good outcomes.

"I find your lack of Fiddle, disturbing" - Darth Vader

Avatar
DanielB
Regulars

Members
November 17, 2012 - 8:46 pm
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline
18sp_Permalink sp_Print
0

I prefer a simple FET preamp, since op-amps can have their own problems, and I prefer how FETs react if they get overdriven a little by the input.  FETs also are easier to get to work well with very high impedance sources like piezo elements.  At least in my experience.

Op-amp chip or simple bipolar transistor circuits are apparently common in at least a lot of electric violins, though.

A preamp can be very cheap to build, if you are used to cobbling together a bit of circuitry.  Otherwise, there are some available for sale at assorted places on the internet.

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Avatar
Tyberius
Members

Regulars
November 17, 2012 - 9:38 pm
Member Since: November 8, 2012
Forum Posts: 555
sp_UserOfflineSmall Offline
19sp_Permalink sp_Print
0

FET's arehandy dandy little self adjusters once you establish offset.

I have built several nice amps from the ground up, even a tube amp that was really nice once filtered. I think my recent experience would tend me to talk the way of Fiddlerman. I no longer have bins of discrete components, perfboard or board etching tools. I probably still have proto boards somewhere, but those days are long behind me.

With todays high end electronics, even the cheapest walmart gadget can outpreform, at least in audio (signal) range and frequency switching of most of the troubleshooting tools I previously used. Tektronix and Hewlett Packard O-Scopes topped off and 100Mhz. Signal tracing/sig gens, digital drivers and sign generators wont even touch limits for troubleshooting and testing of todays electronics.

 

Like I mentioned, FM has the right idea. Until Armageddon hits (Not the Inca one wink ) I think I'll leave circuit building to the Chinese, Germans, and Pakistanis in mass produced markets. I'll just forgo any and all headaches and just buy somethinge if I need it. I'll stick to making myself my coffee. The only gain that needs is a spot of cream and a pinch of suger to taste

coffee1coffee2coffee (and a donut for good measure)

"I find your lack of Fiddle, disturbing" - Darth Vader

Avatar
DanielB
Regulars

Members
November 17, 2012 - 9:47 pm
Member Since: May 4, 2012
Forum Posts: 2379
sp_UserOfflineSmall Offline
20sp_Permalink sp_Print
0

Now, a tube/valve electric violin could be a dang fun concept, though perhaps a bit "steampunk".

"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

No permission to create posts
Forum Timezone: America/New_York

Most Users Ever Online: 231

Currently Online:
21 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Members Birthdays
sp_BirthdayIcon
Today kit, wisco kid
Upcoming Mad_Wed, Andrew, Prudence, ButteryStuffs, makinnoise

Top Posters:

coolpinkone: 3767

Mad_Wed: 2849

Barry: 2661

Fiddlestix: 2637

Oliver: 2439

DanielB: 2379

Member Stats:

Guest Posters: 1

Members: 3564

Moderators: 0

Admins: 2

Forum Stats:

Groups: 16

Forums: 56

Topics: 6448

Posts: 80415

Newest Members:

MACJR, bo, EKBanjo, charlieD, Folky fiddler, Morgenes42

Administrators: Fiddlerman: 11717, KindaScratchy: 1651