nylon electro - impedence issue?

[BEBF#BEb-man]

I've had this nylon string electro-acoustic for about eighteen months. The original preamp started to become intermittent, making a rushing sound. In the last few days I've sourced the same model preamp, an LR Baggs LR-F Timber Plus (not listed on their website, for whatever reason). Seems to be an inexpensive one used on many electros at least by Crafter.

The new one isn't working right. The LEDs light up and I've tested both the new one and my old one by plugging a mobile phone into the piezo socket and listening to that back through the guitar plugged into an amp. (Don't try to get your head round that if it hurts, but it works as a test.) Both work this way. Then I plugged a spare piezo into both preamps, just held in my hand, and with the new preamp the piezo when tapped is considerably quieter. I'm wondering if the preamp as manufactured has a slight variation with one component if it's being fitted to a nylon string guitar rather than steel. When ordering I had stated the guitar model which has an N in it to differentiate it from the steel equivalent.

Does my guess sound right? If so, as my electronics knowledge is not great, does this mean my piezo as fitted is too low in output or impedence or whatever the term is or too high? It is just a strip of kind of mesh stuff, which can bend and has no covering. I'm wondering if it'll be easier to source another piezo or whether the piezos that work with nylon string guitars are necessarily different and that I'd need to stick with this one and try another preamp, whether the same model or from elsewhere.

Thanks. Sorry it's not simple but I've worded this as plainly as I can.

[Garthman]

Hmmmm. The piezo transducer will work on nylon or steel - the piezo crystal just responds to vibration. BTW - the flexible co-axial type of UST is usually better than the rigid bar type.

Try plugging the UST into the preamp, connect to an amplifier, turn up the volume and tap the UST gently along its length with screwdriver blade or similar - you should get a sharp sound each time. If you don't either the UST or the preamp is faulty.

I wouldn't expect both preamp units to be faulty so I expect it's the UST - new ones are readily available on Ebay.

[BEBF#BEb-man]

Thanks. The UST still works with the old preamp I'm replacing. The old preamp is not entirely dead and is currently in a good mood with me it seems. I'm sure it will be dead sooner or later going by the noise it sometimes produces, the rushing sound, so I need to resolve this.

What you said about how the piezo works equally with steel or nylon though is good to know, that closes down one avenue of my wondering. If you or anyone else has any ideas what's up that'd be good. I'm guessing there is one component different in the preamp so that impedence or something jargon-y like that is mismatched, if you see what I mean. Maybe you can express this better.

What would that bendy mesh-type of pickup be called if I were to look on eBay? To suit the new preamp should I be looking for high impedence or low or do they use the word 'output'. I don't have electronics knowledge so I'm just spouting what I remember form reviews and such. I saw a bar-type piezo by Artec that is intended for classical guitar and I briefly had one with a preamp I tried and I know it fits, but if the bar-type is not as good then I'd rather avoid it. Do you mean it's not as good in that the bendy mesh-type has better contact?

Unfortunately I managed to ask the supplier of the replacement late on Friday and they don't seem to understand the issue or are understandably tired and keen to get home. The same person, by coincidence almost, being employed at the distributor of two brands of guitar I own, botched a guitar repair a couple of months ago for me so I'm not feeling hopeful of further sense form them.

Thanks for any further input.

[BEBF#BEb-man]

I have a bit more information now. LR Baggs tell me that the guitar does use their element UST but that they do not make the preamp, only that the preamp is based on LR Baggs spec details. Cheekily it still has LR Baggs printed on it! I looked up the Element and it says in some ads that it won't work with other preamps. It does seem I was sold the wrong preamp. So now I'm thinking do I get another UST. I see the Elements are not cheap so it's unlikely I'll match the sound quality with something costing a fifth of its price. I'll see what luck I have getting the guitar's distributor to acknowledge their mistake. It does seem foolish having a preamp with the same name and casing etc but which has a different spec even if it's down to a mere couple of capacitors or whatever.