Electric Cello Pickup Solutions.

[Gilbert Fredrickson]

I am fascinated with the positively brilliant NS Polar pickup system. How may I find such a bold and effective solution to my electric cello needs? I would like to use the same low profile bridge set up as Ned's herrlich wunder cellos. I have thought of a simple flat guitar piezo set into an arched cavity under a solid bridge, but this seems far too simple.

[Hans Bezemer]

That sounds like a good option.

Also you can use your strings as a coil: http://www.youtube.com/watch?v=Lj5knLzVSns
Or see for a similar approach: http://music-electronics-forum.com/t14952/
and http://www.fiddleforum.com/fiddleforum/ ... ic=19768.0
This is the commercial version of the same concept: http://www.stringamp.com/

An other option is to make a low z single loop pick up:
http://www.mimf.com/phpbb/viewtopic.php ... 118#p23047
for technical info: http://music-electronics-forum.com/t5447/

[G.S. Monroe]

This is brilliant... I just set up a test platform on my bench and tried it.
I built a primitive diddly bo, and used a bolt for nut & bridge. I soldered a positive lead (red wire) to the bridge & a negative lead (black wire) to the nut.
I gator clipped both wires to a EQ-7545R preamp and jacked that to my "First Act" test amp. I started placing bar magnets end to end under the string course ( #12 solid piano wire ) until I got a strong enough magnetic field to get a signal. It took 3 x 2 inch rare earth bar magnets ( 6 inches ) to get a response via overdrive mode on the amp, confirming that it can work in principle. Now, short of running the system through a bulky microphone amp, is there any viable ways to increase the active coil outputs that can be incorporated into the body of an instrument?
I'm going to try something like this to possibly boost the signal, but as for knowledge of electronics, I'm at best a "plug & play" type.
I'm thinking that something as simple as this passive preamp setup could be wired in before the Equalizer Preamp and the combo might give enough "juice" to produce a descent output. Am I crazy?

http://beavishifi.com/projects/Passive_ ... amplifier/

[Hans Bezemer]

Greg,

I'm also experimentating with this concept and I find it promising. If you use the truss rod as a ground return you can make a polyphonic pickup.
One of the downsides is the very weak signal you get (that you allready noticed). The most common solution is to use a transformer to get the signal up to fit a microphone preamp (as descriped in the post on the passive preamp).
I've used a 1:500 current transformer (the same I used for my low z pick up) and the signal was weak but better. Right now I waiting for some 1000:1, 2000:1 and 2500:1 transformers to continue the experiment.
If you want to do some more experiments, I would suggest you (re)read the thread from the music electronics forum, it will give you a good startingpoint.