Tell me about Piezo transducer rods

[Helmholtz]

In order to achieve full mechanical contact saddle with the transducer, may be solution to place a sponge between the transducer and the wood bridge that would press the transducer to the saddle.

Anything soft like a sponge or piece of rubber between the transducer and the bridge base will spoil the guitar's acoustic sound and sustain.
The "secret" is precision (bridge filing, full surface contact) and a good press fit.
I have some experience with installing/fitting piezo transducers.

[vintagekiki]

https://www.youtube.com/watch?v=BL3alVUCmgo
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