Being horrified at the cost of commercial manufacturers piezo violin pickup systems, I decided to design my own..


Rough drawing of the pickup:


The most difficult part of this project was sourcing the components: Ceramic PZT material, small diameter low capacitance braided cable, copper foil tape with conductive adhesive and conductive epoxy. I managed to order the conductive adhesive and foil tape from Ebay UK. For the piezo ceramic element I decided to go with a cheap Artec undersaddle guitar pickup bought from Axes R Us in the UK for a very reasonable 8. I will strip-down the the pickup to remove the six piezo elements (Being careful to note the correct polarisation).
I can also make use of the screened cable. Whilst waiting for the parts to arrive I worked out my design for the pickup. I decided on an embedded design although more versatile, under-the-wing and clamp-on designs seem a bit hit and miss regarding a consistent sound. Personally I believe that most piezo pickups sound very similar to each other and ironically, I don't much like the sound of any of them!  I quickly realised that the most difficult stage would be making the electrical connections to the PZT ceramic. Having contemplated this over several days I came up with the idea of using copper clad board for the positive electrode. This would need to be very thin 1 mm or so. As fibreglass copper clad board is fabricated in layers, I decided to split the board in half. Then I carefully sanded the board to the correct thickness and shape to accommodate the piezo ceramic remembering to leave a little copper exposed to make a soldered connection. I then used conductive adhesive to fix the tinned side of the piezo ceramic to the copper side of the board. Next I soldered the hot inner wire to the board. I masked off the silvered top of the ceramic and then sprayed on several coats of clear Acrylic lacquer to insulate the hot connections. Following 20 minutes of low baking in the oven I removed the masking tape, then I covered the whole pickup in copper foil, then soldered the screen connection to the foil.

Artec PG-607 Undersaddle Pickup.



Finished pickup ready for embedding:



The bridge marked out ready for routing.

Positioned to pick up mostly in the mode 1 plane.



Next on to the fitting. I decided to use one of the Aubert VB3 bridges I purchased from the very helpful 'Violin Man' Up in Dundee. I marked out the routing pattern then carefully routed out the chanel using a mini drill. Then I mixed up some epoxy and applied some to the channel and inserted the pickup until the epoxy oozed out ensuring a good fit. I then applied a bit more to seal the pickup in. I gave it 24 hours to cure then fitted the bridge.


Routed ready for the pickup. (Rough edges will actually help adhesion)

I made a Carpenter style jack mount from some part seasoned macassar ebony I had left over from a tail piece I made for a Yamaha SB 200 electric upright bass. As the one fitted is made of plastic! The jack socket I used was a barrel type used on electric guitars ETC. The adjustable fittings were from a standard chin rest.


My carpenter style jack mount hand made from macassar ebony





The completed pickup. Good string balance, good output and great sound

(If you like the sound of piezo's!)


Making these pickups is quite time consuming however, If anyone would like one, I am prepared to make them without a Carpenter Jack. I will try to source some of these or maybe come up with a simple design.

As should always be the case with Piezo pickups you really do require a high impedance preamp to get optimal sound. The Behringer DI boxes work quite well though they still only have a 1 meg input impedance. Resulting in some low frequency roll off. The L R Baggs Para DI looks good, but my concern is that although it has a 10 meg ohm input impedance, it's too far away from the pickup. In my opinion running such a high impedance through standard instrument cable is asking for trouble. This was an important consideration when I designed my jack plug shell mounted preamp / MicroDI combination. It also has a high input impedance of approximately 10 meg ohms, but it's very close to the pickup. The signal is then converted to a medium impedance inside the jack plug, before it is sent down the instrument cable..


After the developer process, I etch the copper clad board in feric chloride:


MicroDI populated PCB

All of my audio electronics prototypes are designed and hand built by me.
Including the circuit boards which I etch myself.
If I receive enough requests, I will gladly make more..

In my humble opinion, this pickup sounds as good as my Baracus Berry, Baggs and Shadow.
I made a demo of the pickup in my Post Production Studio. The violin is an Amati copy fitted with Thomastik Dominants.
The pickup was recorded via one of my Fet Preamp Leads and MicroDI straight into an RME Fireface: Available soon..

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