Sunday, 9 March 2014

Bouzouki/Gouzouki – an unusual modification

It was a lovely summers day when Jon Sanders brought this interesting job to me.
It’s an Irish Bouzouki with a guitar body – he calls it a Gouzouki.
It’s a great instrument made by fantastic luthier Davy Stuart in Christchurch, now located near Nelson
The instrument has an undersaddle pickup  so it can be amplified. Jon wanted me to make another pickup for just the bass strings so the signal could be completely separate from the existing one. The plan was to run this through an octave pedal to lower it an octave (or two). I’ve done a very similar job for a friend of Jon’s a few years back – Mark Mazengarb.
That job was for a guitar and Mark wanted both E and A strings amplified seperately.
For that one I took a Strat pickup, cut it down to a third of the size and re-wound it.
You can see (and hear) that pickup on the promo clip on Mark’s site:
So, the two problems I need to solve with Jon’s Gouzouki are how to pick up the sound of just one pair of strings and how to attach that pickup to the instrument.
I decide to go for a magnetic pickup. This can be kept completely separate from the existing piezo undersaddle system and it directional enough to only “hear” what I want it to.
I have a pickup winding machine (I repair a lot of vintage Fender and Gibson electric guitar pickups) so I’m happy I can make one that will sound how I want it to.
Just to spice things up there’s a time limit on this one. Jon doesn’t live in Auckland and I only have a few days to do the job. This means I need to find an old pickup former from my box of bits rather than order a new one.
The most suitable candidate is a Fender noiseless Jazz Bass pickup. I know this will have good quality magnets with the added bonus of being able to make it a hum cancelling stacked humbucker.
You can see in this picture I’ve stripped off the original wire (this was a dud pickup) and cut the fibreboard former down to the size I wanted. I’ve wound the bottom coil and am about to do the other.
I’ve decided to wind 1500 turns of 42AWG wire for each coil. The 1500 turns was a bit of a guess – I’ve wound a lot of pickups and you do get a “feel” for it. If I made it too powerful there’s a danger of it overdriving the amp and distorting, too weak and it would simply be too quiet. On reflection, I’d try 1700 next time but there just wasn’t time to experiment.
An action shot of winding in progress – exciting stuff!
Here’s the second coil half wound.
They’ll be wired together in series, the outer winding of one coil attached to the outer of the other. So the continuation of wire will be from the start of one coil to its end, the end of the other coil to its start. This puts them out of phase with eachother (180degrees) and so cancelling the hum. They are also magnetically out of phase (180degrees) which brings them back to being in phase. It’s not easy to explain.
Once wound I dip the pickup in melted wax to hold the windings together and prevent microphonic feedback.
I need to find a way of mounting the pickup so it “hears” the strings, is height adjustable, not in the player’s way, looks elegant and easily removed if necessary.
I decide to make a bracket that can be screwed to the cross brace under the end of the fretboard. The main purpose of this brace is structural strength (resisting the compression force of the strings) so it will be quite happy holding the pickup on.
I make a hardwood bracket. The 3 holes are for mounting the pickup to the bracket. I can put different thicknessed shims under the pickup to adjust the height.
I mounted the second jack socket just below the existing one. We measured up first to make sure his strap would still fit, an important consideration – he’s very attached to his strap.
After the job was completed Jon came in to test it out with his octave pedal. I had to replace the height adjusting shim – but that’s what it was there for.
Overall. I was very pleased with the result.
The following day he was testing it out at The Oratia Jungle Festival
Have a good gig mate.
Feel free to contact me about repair work (if you are in NZ). I only check emails weekly so the workshop phone is always the best 09 307 6501.

Workshop Hours

Mon……. 8-6
Tues……. 8-6
Wed…….. Closed
Thurs …..8-6
Fri ……….8-6
Sat/Sun ..Closed

Mr Glyn’s Guitars

21a Khyber Pass Road
New Zealand
09 307 6501, 021 912678

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