Making an Electric Viola - Pickup ideas?

[jameskpolk]

So...electric viola (4-string)...pickups.

I'm pretty set on piezos rather than magnetics, now I'm just thinking about where to put 'em. Since I'm building this thing from stratch and making it crazy-skinny and whatnot, they're going to go on the bridge...there's no beautifully vibrating top to stick them to.

I've thought about four small elements placed between each string and the bridge, or two elements on the back of the bridge and another one under each foot, or just one or two on the back of the bridge.

Thoughts? Recommendations on a supplier of small piezos?

Oh, yeah, I want to get something that is equally sensitive to bowing and pizacatto--so both horizontal and vertical movements. That's why I like the first two options the best...

*Edit* and unless it's cheap and sounds good, I'm not going to by any pre-made pickup. The Barbara would be nice, I know, but $450 is waaaaay outta budget for me.

[Dave Kerr]

You might start with this thread. There's been a few discussions here over the years related to piezos and preamps.

[David King]

Well, either you are going to pay for a system that sounds 1/2 way decent or you're going to reinvent the wheel and figure it out for yourself. The dots are cheap, get a couple of them and move them around until you get a sound you can live with for pizz and arco and then tell us where you put them. I'm willing to bet the location with vary for every instrument.

[salvarsan]

For my taste, the piezos don't have enough bass without excessive equalization,
and add their own tapping-on-credit-card flavor to any percussive attack, rather,
they suck and I hate them.

You might try building an ultra-low impedance pickup such as those discussed
and pioneered by bbsailor in other threads here.

This was a single-loop of 1/8" copper tubing run through a toroidal current
sense transformer whose output was sent to a low-Z impedence-matching
transformer usually used for microphones. Output from the prototype was high-
fidelity, somewhat low amplitude but noise-free.

Where guitar pickups are 5-10k ohms, this one was ~300 micro-ohms,
hence the two stages of transformers.

The copper tubing was bent to conform to the cello fingerboard. For proof of
concept, the magnets were cheap ceramic from Home Depot.
bbsailor was more exacting and got good results with Neodymium mags
on a U-shaped steel tray to focus the magnetic field.

A cheaper one using two EI current sense transformers had more output
but was more difficult to mount.

-drh

[jonson]

transducer placement.

there has been hundreds of patents on violin/viola pickups over the years including Leo and Harry Dearmond , Fishman. Barbera etc so you could get placement ideas from some of these.
Pats. 2486264
3291887
3539700
3003382
3600496
6018120
6515214
4860625
4785704
4867027
7319188
and lots more listed.

[jameskpolk]

Ho ho ho thanks!
Looking in to all of these...

[Spence]

So...electric viola (4-string)...pickups.

I'm pretty set on piezos rather than magnetics, now I'm just thinking about where to put 'em. Since I'm building this thing from stratch and making it crazy-skinny and whatnot, they're going to go on the bridge...there's no beautifully vibrating top to stick them to.

I've thought about four small elements placed between each string and the bridge, or two elements on the back of the bridge and another one under each foot, or just one or two on the back of the bridge.

Thoughts? Recommendations on a supplier of small piezos?

Oh, yeah, I want to get something that is equally sensitive to bowing and pizacatto--so both horizontal and vertical movements. That's why I like the first two options the best...

*Edit* and unless it's cheap and sounds good, I'm not going to by any pre-made pickup. The Barbara would be nice, I know, but $450 is waaaaay outta budget for me.

You want the earth for nothing eh? I would suggest you link some old record player cartriges together with the 'needles' just touching the underside of the finger board.

[jameskpolk]

You want the earth for nothing eh? I would suggest you link some old record player cartriges together with the 'needles' just touching the underside of the finger board.

Well, yeah...don't we all? That's an neat idea, but being connected to the fingerboard, I fear picking up my fingers hitting the board? Fears unwarranted? I'll see if I have any lying around (cartriges, not fears) to experiment.

[jameskpolk]

For my taste, the piezos don't have enough bass without excessive equalization,
and add their own tapping-on-credit-card flavor to any percussive attack, rather,
they suck and I hate them.

You might try building an ultra-low impedance pickup such as those discussed
and pioneered by bbsailor in other threads here.

This was a single-loop of 1/8" copper tubing run through a toroidal current
sense transformer whose output was sent to a low-Z impedence-matching
transformer usually used for microphones. Output from the prototype was high-
fidelity, somewhat low amplitude but noise-free.

Where guitar pickups are 5-10k ohms, this one was ~300 micro-ohms,
hence the two stages of transformers.

The copper tubing was bent to conform to the cello fingerboard. For proof of
concept, the magnets were cheap ceramic from Home Depot.
bbsailor was more exacting and got good results with Neodymium mags
on a U-shaped steel tray to focus the magnetic field.

A cheaper one using two EI current sense transformers had more output
but was more difficult to mount.

-drh

A little bit of reading-up later...when you did this on cello, how'd you rig up the ground return from the strings (up by the stroll)? Looks to me like the most (only?) aesthetically pleasing way to do this is to pop the fingerboard off and run a wire in a tiny, tiny groove down the length of the neck, and connect the strings to said wire with some sort of metal clamp, or a brass nut as suggested for guitar.

Interesting...you may not have converted me, but I'm curious enough to try building one of these kids...

Oh, and piezos: do you find them sucky even when run through a buffer? That should take care of the bass issue, in my understanding. Anyways, I'm liking the idea of a low-impedance pickup mixed with a buffered piezo for a little more percusive flavoring. We'll see how it all turns out.

[jonson]

cheap

morn Spence.
To me cheap is one of those round piezo buzzer elements from Maplin at 90p and cut it up to make a lot of small ones. Iv'e done that so can't be too difficult.

[Spence]

What a shame Sam Lee Guy's not here anymore. He once told me about a Chinese violin pickup that was made by winding a coil around a toilet roll inner and put inside the violin.

I do know that there is a website somewhere where a guy made a violin pickup using a sewing machine bobbin. Apparently it was very good.

[salvarsan]

when you did this on cello, how'd you rig up the ground return from the strings (up by the stroll)?

The pickup was a two-wire device with a floating shield. The cello was little more than a fingerboard on a skeletal body, i.e., it was designed for use with a transducer.

Oh, and piezos: do you find them sucky even when run through a buffer? That should take care of the bass issue, in my understanding.

The piezos amplify EVERYTHING -- your fingers sliding on the strings, the scroll brushing against your shoulder, the unipod's rubber squeek against the floor, anybody walking nearby...

When you equalize for more (rather, _enough_) bass, you also bring up the low frequency noise.

If you handled singer amplification similarly, you'd hear every heartbeat, gastric gurgle, tendon stretch, and joint creak.

The 'cello' was minimal, should be attached here:

[jonson]

slightly different

Came across this guy a little while ago and thought it was fairly neat. Not come across piezo washers before.

http://www.endolith.com/wordpress/20...ectric-violin/

[jameskpolk]

Came across this guy a little while ago and thought it was fairly neat. Not come across piezo washers before.

http://www.endolith.com/wordpress/20...ectric-violin/

Yeah, seems like it might be a little more durable for an under-bridge pickup. Violin and viola bridges have a tendancy to lean forward after a while due to tuning--I don't know for sure if that shift in pressure could screw up a bit of piezo film, but I am wary of it.

A quick search reveals no suppliers of piezo washers, but I'll keep at it. Also asked "the guy" for sound samples.

[jonson]

supply

something for you to look at on page 12 of this brochure and the site is worth a look round. . http://www.murata-northamerica.com/