After a somewhat casual search, I cant find any mention anywhere of how this pickup technology actually works. Only someone wanting to sell me something.
Background is I purchased a "parts / repair" instance off ebay. A little saddle mounted affair with a coin cell battery. I figured I could always make use of the pre-amp part, if I was not able to repair it. I could not, it was mechanically damaged.
On inspection of the battery powered circuit, it's entirely passive. No op-amp, no transistor - nothing except a few two "pin" SMD components, the jack, the battery holder and a miniature volume potentiometer.
This got me curious, so I started to strip away the heat shrink cover over the pickup rod. There's a couple more SMD parts there at the preamp end, apparently a resistor and capacitor in parallel. The element itself looks like a "Flex-Print" type of Kapton based material. I could not scrape away any coverage to get probe contact to see if the element - what's left of it - is resistive.
Whatever it is, it must be one tough little strip of material. The instructions came in the box and the pickup routing is insane. The majority of the strip goes underneath the bridge in the saddle slot as usual. Then it takes a hard right angle turn, up the side of the bridge, which you're supposed to shave the end slightly to accommodate the element thickness. Then a second, nearly right angle turn to the battery / circuitry enclosure, which is stuck onto the saddle with double sided sticky mat.
No piezo pickup, constructed of six individual bars of piezo material held in conductive channel, could mechanically take such an arrangement. So what is it?
FWIW Shadow is still in business and will sell just a "NFX" bridge pickup element for about $45, shipped. That's entirely reasonable, but like many engineer / musicians (I'd bet), I want the "lecture on Heaven" before walking through that door. Like a clear description of the operating principle, i.e. how it's able to work with just a voltage and passive support circuitry. How it can withstand right angle bends without breaking immediately?
Additionally, I have a Kala guitar with a Shadow pickup system. I bought it at a yard sale with the saddle ripped off the top. I've reglued the saddle twice and had it explosively come off, for a total of 3 times its pickup element has got the tar beaten out of it. It still works, which is the only clue I have suggesting that it too is of the unknown "NFX" technology.
Background is I purchased a "parts / repair" instance off ebay. A little saddle mounted affair with a coin cell battery. I figured I could always make use of the pre-amp part, if I was not able to repair it. I could not, it was mechanically damaged.
On inspection of the battery powered circuit, it's entirely passive. No op-amp, no transistor - nothing except a few two "pin" SMD components, the jack, the battery holder and a miniature volume potentiometer.
This got me curious, so I started to strip away the heat shrink cover over the pickup rod. There's a couple more SMD parts there at the preamp end, apparently a resistor and capacitor in parallel. The element itself looks like a "Flex-Print" type of Kapton based material. I could not scrape away any coverage to get probe contact to see if the element - what's left of it - is resistive.
Whatever it is, it must be one tough little strip of material. The instructions came in the box and the pickup routing is insane. The majority of the strip goes underneath the bridge in the saddle slot as usual. Then it takes a hard right angle turn, up the side of the bridge, which you're supposed to shave the end slightly to accommodate the element thickness. Then a second, nearly right angle turn to the battery / circuitry enclosure, which is stuck onto the saddle with double sided sticky mat.
No piezo pickup, constructed of six individual bars of piezo material held in conductive channel, could mechanically take such an arrangement. So what is it?
FWIW Shadow is still in business and will sell just a "NFX" bridge pickup element for about $45, shipped. That's entirely reasonable, but like many engineer / musicians (I'd bet), I want the "lecture on Heaven" before walking through that door. Like a clear description of the operating principle, i.e. how it's able to work with just a voltage and passive support circuitry. How it can withstand right angle bends without breaking immediately?
Additionally, I have a Kala guitar with a Shadow pickup system. I bought it at a yard sale with the saddle ripped off the top. I've reglued the saddle twice and had it explosively come off, for a total of 3 times its pickup element has got the tar beaten out of it. It still works, which is the only clue I have suggesting that it too is of the unknown "NFX" technology.
I found a patent from the same company about something else that has one interesting sentence in its description:
https://patents.google.com/patent/DE10309838A1/en
In the (translated) text, it says: "Use of piezo-ceramic sensors, piezo film sensors, Piezo polymer sensors or Back electret sensors for the piezo sensor according to one of claims 1 to 16."
Apparently piezoelectric film sensors and piezo polymer sensors exist. Could either of these be the flexible sensor type you are interested in?
https://patents.google.com/patent/DE10309838A1/en
In the (translated) text, it says: "Use of piezo-ceramic sensors, piezo film sensors, Piezo polymer sensors or Back electret sensors for the piezo sensor according to one of claims 1 to 16."
Apparently piezoelectric film sensors and piezo polymer sensors exist. Could either of these be the flexible sensor type you are interested in?