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I’m thinking about installing a piezo pickup in the archtop bridge I’m working on. How is this usually done? Is the saddle pressed onto the pickup and then glued in place or is it just held in with the weight of the strings?

It's no different than any other UST (under saddle transducer) with the following some of the considerations to address.

1). On an archie it's intonated by moving the saddle forward or aft in the absence of any adjustable saddles that some arch tops have with g*bson being one example at times. So if you run the wire through the foot are you still going to be able to move the entire bridge forward or aft to compensate for they client's strings? If not this should be addressed with my point being a UST may not be a good choice for this arch top.

By the way the F holes are not just another pretty face in arch top tradition. The points on the F holes have been used by countless makers for many years as a starting point for saddle location for proper intonation. If when restringing we locate the bridge in alignment with the F hole points on older arch tops built with the F holes in sync with the scale length the intonation will be in the starting ball park. A lot of people have never heard this and tell me they learned something.

2). Yes the tension of the strings holds the saddle in contact with the UST element. Be sure the saddle is not loose fitting but still can move up and down freely or it will stifle and strangle the UST's ability to sense the vibration of the saddle, strings, etc. A very well fitted saddle is prudent here and it should not be snug or loose.

3). The saddle bottom must be perfectly flat or EQ issues may result with a lack of treble or bass. Likewise the saddle slot must also be perfectly flat for the same reasons.

Typically an aftermarket or different kind of pup is used to amplify these for some of the reasons that I've mentioned. I've never installed a UST in a arch top and I am not sure if my business partner ever has either. Instead we have installed dozens and dozens of aftermarket pups engineered for arch tops but not USTs.

If you are already vested in what you are doing and can find a work around so that the entire bridge can be moved forward or aft I understand. If not this is not the kind of pup I wold install in an arch top.

Also, very nice looking bridge, nice lines, well done.

Epiphone is installing under saddle transducers in their reissue Masterbilt archtops and I have seen them on a few other acoustic archtops. You are right, the floating bridge does need a little room to move back and forward, but not a lot. Currently, I have carved out the feet which reduces the weight and gives it some room to move. Perhaps I should carve out a little more.
The saddle is snug but I can pull it out of the slot with my fingers. Without gluing it, do these types of transducers absorb some of the string vibrations? It seems like they might. Is this a problem?

I’m not a fan of USTs ... on anything! They have a characteristic sound that grates my nerves. A soundboard or bridge mounted piezo eliminates the annoying “quack”.
If I was in your position, I’d have a look at the Bouzouki PUPs at https://www.schattendesign.com/new-website.html. They are a 2-1/4” x 1/4” piezo that sticks to the back of the bridge. They also have “patch” piezos that could stick to the underside of the soundboard. You could contact Les Schatten through the tech support web form — he’s extremely helpful, especially for odd applications. He is a guru for piezo pickups on just about anything and he certainly has everything on his shelf to prepare a unit for your guitar.


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Hey thanks. That’s something I’ll look into.

I built a semi archtop that the owner said he would never plug in but just to hedge my bets I installed a K&K piezo inside while the back was off (no way to install thru the f-holes)



I tucked the jack inside the guitar with a piece of string thru a cork in the hole so I could pull it into position after the guitar was finished. Turns out he has plugged it in

I've done three like that minus the bridge plate and am very pleased with the plugged in sound. I do have a K & K external pre-amp for when I play large venues but haven't had to use that yet!