NFV1 Piezo is cutting out when I play kinda hard

[Androo]

Hello everyone,
I'm thrilled to find this forum but bummed to need it. I have an NFV1 I bought new in '96 and am still in love with. I hardly used the piezos though over the years. I just got a Fractal FM9 that gives me two inputs (and godlike sound) and started working on getting a clean tone but I find that the piezos are cutting in and out if I play kinda hard, especially palming the low E. I've checked the wiring as much as I can without taking the bridge apart and it's all good. I recently changed the volume pot but can't say whether this problem pre- or post-dates that operation as I fixed my volume knob while waiting for the FM9. Anyway, I'm confident the wiring is good.

This model has the passive piezos and I couldn't find anything specific to this early model in the manuals in this site. Any advice on how to troubleshoot? I looked in the back under the bridge and those wires all look right, too. I have not dared to monkey with the saddle pieces apart from intoning the strings.The intermittent connection worries me...these things tend to go one way. It did occur to me that there could be dust built up under there and I considered blowing it out with compressed air but since I don't know exactly where the piezo elements are I didn't want to roll those dice.

Any thoughts would be most appreciated.
Cheers,
Andrew

[vjmanzo]

Hi @Androo! Glad you’re here—welcome!

So, there’s no preamp in the chain between your NiteFly piezo output and the input of the Fractal?

Something like this might be the solution if the issue is related to an impedance mismatch—as you may know, the first two versions of the NiteFly had the passive piezo and were designed to make use of the NiteMix external piezo preamp. If the issue you’re having is not related to something like I’m suggesting, the issue may be mechanical; are you using good quality strings with a tuning that produces enough tension (standard tuning with 9s or 10s for example)?

[Patzag]

My first question would be to find out if all the output cuts out or only the E string piezo?

If it’s an impedance matter, then this might be useful:
https://www.radialeng.com/product/pz-di

[Androo]

Hi everyone,
thanks for the welcome and the replies. It's direct into the FM9, no preamp. When thing are behaving well, it's clear there is no need for a pre- and it sounds great. I am confident it's not impedance. There is a distinct "break-up" to the sound as the piezo pickups are cutting in and out.

When it degrades or cut-out, it's all strings. The culprit appears to be at the Low E. It sure seems like an intermittent electrical connection. The only place I can tell where the all come together is underneath the bridge but that all looks right. I think the root problem is under the intonation adjuster for the Low E. I just don't want to take it apart because I don't know what is under there or how it's connected. The only thing the manual says is: be careful adjusting these because the piezos are fragile... but there is no mechanical/electrical illustration I can find to show me what I might be in for if I tried to remove that part. Intermittent is better than dead.

Best,
Andrew

[Androo]

piezo wires contacting bridge

It happens sometimes that by seeking help one can help themselves. I took some close-ups of the bridge where the piezo wires come through in order to illustrate that the factory wiring looked right and was intact. I zoomed in and then I saw it. The slots in the bridge do not allow for the sliding saddles (for intonation adjustment) to go all the way back without the bridge housing interfering with the wires. Or...the piezos were soldered too far to one side.

I slid them forward a bit and now it seems that the electrical problem is gone (so far... for now...) and the output from them is noticeably louder. Crazy. My intonation is unfortunately slightly off now.

Now...back to the fun stuff I hope

NFV1

[Patzag]

Congratulations on fixing the problem.
Sorry to hear about the intonation issues.
How bad is it?
If you’re adventurous, you could try to expand the slot a bit with a deemed tool. (With the saddle removed of course).
But I’m surprised that the issue exists at all.
What kind of strings do you use?

[Androo]

Thanks Patzag,
You're reading my mind with regards to the strings. I'm using D'Addario 10's but the guitar was set-up for 9's. I think I'm going to switch back down and see where that take me. I think my next most brave move would be to re-touch the solder at those Piezo wires if it persists. It's clearly the wiring. When I tapped the one on the low E, I could hear it. Also, there was noise when moving the whammy-bar from the wires rubbing on the bridge metal. I too am surprised that this is even a thing.
Cheers,
A

[Patzag]

Thanks Patzag,
You're reading my mind with regards to the strings. I'm using D'Addario 10's but the guitar was set-up for 9's. I think I'm going to switch back down and see where that take me. I think my next most brave move would be to re-touch the solder at those Piezo wires if it persists. It's clearly the wiring. When I tapped the one on the low E, I could hear it. Also, there was noise when moving the whammy-bar from the wires rubbing on the bridge metal. I too am surprised that this is even a thing.
Cheers,
A

You're welcome.
Careful with the wire coming out of the saddle. It's quite fragile and there have been instances of the wire breaking at that point. That's fairly unrepairable.
Good luck!

[Patzag]

Oh! And by the way, congratulations on your FM9. It's a beast and sounds fantastic!

[Androo]

...Careful with the wire coming out of the saddle. It's quite fragile and there have been instances of the wire breaking at that point. That's fairly unrepairable.
Good luck!

Ah! That's what I'm trying to understand! Why is that unrepairable? I hope going back to 9's and moving the saddle is the only thing I need to do but can't the wires be re-soldered to the piezo pickups? I really, really don't want to go there but...

As for the FM9, that was my mid-life crisis buy. I told my wife: I can get a sports car, a mistress, or an FM9.

[Patzag]

To be honest, I based the unrepairability on what others have said. I have not experienced that myself, because I’ve never had the issue. @mmmguitar might have more information on the subject.

You definitely chose the cheapest of the three. But probably the one that will last the longest! Have fun!

[vjmanzo]

Why is that unrepairable?

Removing and the reapplying the epoxy to the piezo disc while bonding it to the saddle can be difficult if it’s necessary, and, depending on how it’s broken, reattaching those tiny leads to that piezo element may require you to deal with the epoxy in some capacity. Doesn’t make it impossible to repair, but it can be really annoying when you think the piezo is reseated close enough to the saddle only to realize that it’s not and, as a result, one string is a little quieter than the others. Hopefully it doesn’t come to that!

[mmmguitar]

@mmmguitar might have more information on the subject.

Here's a video from member @Paul Marossy detailing an unfortunate truth concerning piezo element saddles for electric guitar: They're engineered to be replaced; rather than serviced.

Based on the symptoms and mitigations already posted in this thread, I get the impression that at least one piezo lead has become brittle over the decades. You probably straightened out a kink by sliding the saddle forward. If you dare, you can remove the intonation screws for each saddle and lift them up to check how brittle the wires have become over time. Carefully reseating them with any kinks in the wire eased may alleviate the issues until the connections further degrade, or cause an internal connection to break completely.

Parker piezo saddles are still being produced by Graphtech in sets of 6; and they're all we currently have to work with. I'm afraid anyone wishing to keep their hardware "vintage-correct" is in the position of soliciting for era-specific saddles here in the Classifieds or in the FB groups.

That all being said, heavier strings will supposedly induce more voltage and generate a stronger signal in piezo saddles than lighter ones. The guitar "originally being set up for 9s" should only affect tuning stability at the nut slots cut for a 9-42 set; and not piezo performance.

[Androo]

Thanks very much for all that information, that's exactly what I needed to learn.
I think and hope that it's just the wire and not the pickup itself. One thought is to try to reinforce the dodgy one with conductive epoxy instead of trying to re-solder, because I could probably do it without taking the saddle off. I'm a bit worried about that now that I see what is what. It's also such a pain with the hardware design in that you have to remove everything and then put it all back before you can tell if you've succeeded or failed.
I'll have to give this some careful thought before I take any major step.
I really appreciate the input and will post back as progress is made (or lost...)
Best,
Andrew

Edit to add: my thought with the string gauge was that the 9's might alter favorably the saddle position I need to be well-intoned, which seems like where I got into trouble to begin with.

[mmmguitar]

Edit to add: my thought with the string gauge was that the 9's might alter favorably the saddle position I need to be well-intoned, which seems like where I got into trouble to begin with.

I see your reasoning, now. Please let us know if there are any changes.

[Androo]

Hello,
I wanted thank the forum again for the important feedback, and to post a brief follow-up.

The intermittent cut-outs are, presently and hopefully forever, a thing of the past after nudging the saddles slightly forward. Fortunately the piezos aren't broken. Putting 9's back on made little to no difference but the tuning stability is probably better. The intonation is still off a touch on two strings but I'm paranoid about moving the saddles again. Maybe some day I'll take them off and re-solder the contacts so they don't interfere with the bridge but at least it's nothing urgent now.

Kind regards,
A