Official Luthiers Forum!

Need help:
Where the best place to put this Piezo under sadle pickup (coax) for Acoustic guitar (Grelier OOO)...
thank's herry....

May be best to put it under the saddle?

Seriously, what is the make? I take it you have no instructions.
Here's a crib from the net I found some years ago for fitting replacments, which I hope may help (sorry for my laziness) -

some (such as the L.R. Baggs LB6, EMG AT, and Fishman Acoustic Matrix) are angled 90 degrees to the top, while others (such as the L.R. Baggs Element and Ribbon Transducer, B-Band, D-Tar, and Highlander) need a hole drilled at about a 45-degree angle. The main concern is to avoid drilling though a top brace, which could structurally compromise your guitar. Most flattop guitars have top braces under the saddle-slot area, so it’s very important to make sure you don’t hit one with the drill bit. Since the saddle slot is usually tilted for compensation, you should try both ends of the slot because one may work better than the other. For example the bass side of the saddle slot may be closer to an X brace than the treble side, so drilling a hole through the treble side would be the best choice. In extreme cases, brace location may dictate whether or not a 90-degree pickup lead can be used at all. With transducers that need an angled hole through the top, the angle can usually be adjusted so the hole comes out on one side of the top brace.
Pickups that have coaxial cables, such as the D-Tar Timberline, Fishman Sonicore (used in several OEM Fishman systems), and Highlander, also require extra attention. These pickups are often installed in a semicircular groove in the saddle slot, and if you wish to replace one with a flat transducer, the saddle slot will have to be rerouted and possibly plugged and recut to provide a proper fit for the new pickup.

So if the undersaddle pickup piece (transducer) is round (which it looks to be from your small picture), you will probably have to use a ball ended mill to cut the the saddle slot, and it looks as if the hole through the soundboard may have to be drilled at 45 degrees - it looks like it is not designed to bend sharply at right angles.

Good luck, and I am sure others will chip in.
By the way, I like the look of the Grellier plans - please give us your thoughts on the plans and post picture/soundclips.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

yep .. under the saddle - it wont work anywhere else - it derives its output voltage at any given frequency from the fluctuations in string pressure when the strings vibrate.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

thank's Colin,
I've just the information installation for EUB (Electric Upright Bass), that piezo buried under the sadle,
but there enough place to burie the piezo.
But for flat top acoustic guitar, whether these guidelines may apply....???

Is this pick up designed for a guitar, or for a double bass?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

For EUB Electronic Upright Bass from Liutaio Motolla, they have free plans not for commercial use and may not be redistributed.
http://liutaiomottola.com/instruments/libellula.htm
http://www.liutaiomottola.com/PrevPubs/Piezo/CoaxTransducer.htm
And all about that instrument from Motolla you can search:
liutaiomotolla.com
and this pickup for all string instrument... you can buy here apart:
Experimental Musical Instruments
and the pre amps you can buy here:
http://www.cafewalter.com/cafewalter/fetpre/index.htm

This upright bass use the Piezo (coax) under sadle pickup (buried under sadle), when I bought that piezo (with pre amp from Cafe Walter), I found the info if this Piezo can be use for almost all acoustic instrument, so I try it to my acoustic (Grelier OOO) but I don't know the best place...

Libellula Electric Upright Bass

The Libellula is a wearable electric upright bass (EUB). It hangs from a strap (two, actually) like a guitar and weighs just 5 ½ pounds. It features a solid mahogany body/neck, a traditional pegbox and scroll, and a high mass high compliance bridge with piezo transducer. The Libellula is a pizzicato-only instrument with a 35” scale, so it is an ideal instrument for the bass guitarist. Full-size plans are available for this instrument as are some pictorial assembly details. (January 2005)

Hi Harry,

If you have to install that piezo with the illustrated "angled access hole", then you might be in for trouble. You quite probably will be drilling that angled hole through the X brace. You don't want to do that! You may be able to avoid the brace, but make sure before you drill.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)