Changing Piezo Coax Cable for Ceramic Piezo Element

[astaf]

Hello guys,

I'm new to this forum. I found it by chance on google while i was trying to find a solution to my problem, which is a piezo problem that i couldn't find an answer on this site too. So i decided to post a new thread.

Well, i have an alhambra 1p classical guitar. 2 years earlier i decided to amplify it and gave it to a so called "luthier" who actually didn't do it as he was supposed to do. And since he is far to where i live i decided to repair it on my own.

The problem is a balance problem i guess. The best sounding string is the b string.
So, if;
B string sounds 100%,
High E string sounds 90%,
G string sounds 10%,
D string sounds 30%,
A String sounds 40%,
Low E string sounds 35%.

By the way, the saddle is straight. I checked it. There is no curving. So i am sure it fully presses on the piezo cable.

So what i suspect is the piezo. I thought if i could change it, everything would work fine. But i am no luthier. So, i need some advices.

Here is the preamp that i have


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Back of the preamp


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The circuit board on the back, the little green thing with the two screws contains the wires that comes out of the piezo coax cable.


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I took a close look to the piezo and found out that it's been torn apart here and there. Here is the photo of it.


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And the photo of inside of the guitar through the hole of preamp


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And a closer one where you can see the piezo's starting point where it cuts through the top of the guitar and lays down the saddle.


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Do you know what might be the problem, any ideas? I suspect the piezo cable due to its condition, it shows some wear here and there.

I also have another idea of changing the piezo with Artec's ceramic piezo element. Here you can see it


So the problem about this is it has a different end than my cable. One has a jack end, the other has two cable ends soldered on the circuit board.

So can i just buy the ceramic piezo, cut the jack end, split the wires and solder them on the circuit board? Would it work? Any ideas?

Thanks for everyone who participates.

[Sock Puppet]

Hi,

Yes, that Artec element would work well with your preamp providing it fits the slot in the bridge well enough.

There're a few of stewmac "trade secrets" that are worth readling:

Trade Secrets! Newsletter at Stewart-MacDonald

Trade Secrets! Newsletter at Stewart-MacDonald

Trade Secrets! Newsletter at Stewart-MacDonald

Hope these are of some use.

[astaf]

Thanks a lot, mate. Sure it will help.

I think i have to take some time and experiment a little.

[Gtr_tech]

Those saddle pickups are not all the same. You need to measure the string spacing from low e to high e in MM and get a pickup that matches that spacing. There's 6 seperate piezo chips in that strip and each one needs to be directly under a string for it to do its job properly. And....you have to make sure you don't crush the piezo strip or flex it too much. The chips will crack/break and not work then. Seating for both the p-up and saddle is critical as well. The slot in the bridge must be totally flat as well as the bottom side of the saddle or else there will be dead/weak strings. I think yer repair guy didn't know about the string spacing needing to match the p-up. Take it back to him and have him get the correct p-up.

[astaf]

Those saddle pickups are not all the same. You need to measure the string spacing from low e to high e in MM and get a pickup that matches that spacing. There's 6 seperate piezo chips in that strip and each one needs to be directly under a string for it to do its job properly. And....you have to make sure you don't crush the piezo strip or flex it too much. The chips will crack/break and not work then. Seating for both the p-up and saddle is critical as well. The slot in the bridge must be totally flat as well as the bottom side of the saddle or else there will be dead/weak strings. I think yer repair guy didn't know about the string spacing needing to match the p-up. Take it back to him and have him get the correct p-up.

Thanks a lot for the advices but i am first going to adjust my saddle according to the links that Sock Puppet posted. If they work then i don't have to change my piezo. Unless it works, i'll continue with your advices.

[astaf]

-----------PROBLEM %90 SOLVED------------

Hello guys,

I did 3 things:

1. I made sure that the bottom of the saddle is even. (which didn't work)
2. I took the Sock Puppet's advice and filletted the bottom two edges of the saddle where it contacts the piezo. (which didn't work)
3. And finally, rotated the saddle so that in the place where the low e string lies, now lies the high e string. And this rotation solved my problem. My guitar sounds 90% better.

Actually i really can't say which of the steps above or maybe all of them together solved my problem or not. But now it sounds better, that's for sure. And why i say 90% is because there are still some balance differences between the strings but it is very very good comparing before.

So thanks again to everybody for the advices.

[Gtr_tech]

Does your saddle look like this?
http://www.sheehans.com/images/help/...ted-saddle.jpg

If so, you can't switch that around or the intonation will be screwed in a big way. If its just a plain one thats even all the way across then you can swap it around, but when you do that you end up with higher action on the high e and lower action on the low e....the opposite of how it should be. Proceed at your own risk....

[astaf]

Does your saddle look like this?
http://www.sheehans.com/images/help/...ted-saddle.jpg

If so, you can't switch that around or the intonation will be screwed in a big way. If its just a plain one thats even all the way across then you can swap it around, but when you do that you end up with higher action on the high e and lower action on the low e....the opposite of how it should be. Proceed at your own risk....

Hello, thanks for the heads-up. My saddle has a really little difference of height between the high e and low e strings. So it didn't cause me any problems about the action. It is a classical guitar, just to remind you. I mean a nylon string guitar which may be different in some ways than a steel string acoustic guitar.