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I am having trouble with a piezo pickup on a U-bass. I would like to replace the existing under-saddle piezo but finding four-string pickup is difficult. Can I cut the excess length from a guitar pickup to fit and will it still work?

Bob

Try a Mi-Si pickup.

_________________
Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Back in the day as I mentioned before when you guys brought up the U-bass offerings the store that we did ghost repairs for (we were contracted to do their repair work, no we didn't do fret dresses for ghosts... ) they sold the U-bass line.

Seemingly every one that they sold came back with bad pup balance issues. It wasn't something that developed over time, these things sucked right off the shelf.

Anyway what's wrong with the things is the engineering and in my opinion a different piezo won't help. The issues are the combination of scale length, string material (plastic) and the lack of downward pressure or break angle on some of the strings (design of the bridge as well) prevents any piezo from stimulating the crystals evenly.

Don't know if you can cut a guitar UST and still have it work but I do know that if it breaks you will have a hard time sourcing replacements at a reasonable price. USTs are super fragile and wrapped in very thin foil and very much subject to damage if handled roughly.

Although cool the U-Bass implementations that we saw some years back were never ready for prime time because of the pup issues.

Have you tried all the typical fixes for the original UST?
I recently got one to work much better just buy fixing up the saddle/bridge/ust contact problems that came from the craptory.

You could get a Fishman "Sonicore" they can be bent any where along the length, the excess just hangs inside the body.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Just asked LRBaggs a question regarding UBass. Long story short, I have an Element Nylon that is set aside for this potential project.

Guess all the Five.O's stay in Ukulele.

The element is a great pup. If you can augment the bridge design to increase break angle, string ramps or some trick that increases break angle your pup balance will have more to work with. Also be sure that the bottom of the saddle slot is true. Lots of pup balance issues result from un even pressure on the UST caused by an uneven bottom in the saddle slot.

Bob
You can cut the transducer shorter. The pickup is merely a ceramic or crystal that generates a voltage. The voltage generated it conducted through two wires.
There are different formats, one has a round cross section, the transducer is coaxial, meaning there is a conductor down the inner centre, the other is a layer on the outside. You can just cut them like a cable with cutters or use a dremel cutting disc, but check the cut end to ensure the conductors are not shorted.
The other is flat with a top and bottom conductor. I have seen broken ones working (up to the break) so cutting would be ok.
There will probably be some changes to the response due to the impedance change when being shortened. I worked out a way of testing the pickup impedance at different frequencies, thus frequency response.

I have a few, because I sometimes change them for people who break them. I will try to measure the change on one by cutting it, but can only find time on weekends.

Thanks Guys !

The design is my own and uses the Hana Lima style tie-through bridge. I would have pictures if I knew how.
I can see the six piezos in the pickup and my question is ,I think, are they wired in series or in parallel? If they are in parallel, removing two will leave four operating but if they are in series, the connection will be broken.
The acoustic sound is pretty good but not enough to be heard with three or four guitars.
I have a couple of cheapies on order from ebay so I can test it for real.

Thanks for the help.

Bob

LRBaggs Element is not string number dependent, and you can't cut it. This goes for the MiSi as well, since they use Baggs' UST wire. Basically, a drop in installation for you.


I angle my saddle slot 7 degrees. The angled slot is one of those things that solves problems you didn't know you had, even without a pickup. I would imagine it's even more important for a UBass.
Just made a new jig for it using a plunge router instead of router table.