Piezo under saddle signal too strong

[julesb]

Hi all,

 

I've just installed/replaced an undersaddle piezo in my previously butchered (😀not by me!) Godin A5 and although it works, the signal is overloading my recording interface even with the gain set to minimal. I've had to turn down the volume on the onboard pre to stop it distorting. I'm sure I've made a schoolboy error so can someone tell me what it may be? I have vague memories of some sort of resistor somewhere from the pre-amp to the battery but I can't remember as this project has been on the shelf for a while and I didn't take any pics beforehand (another schoolboy error)

 

Many thanks,

Jules

[Frank Blank]

I have the same problem with my piezo basses so I'm following with interest.

[itu]

Piezo creates high voltages compared to a magnetic pickup. The impedance (Z) of the output is also very high, in the mega ohm range (magnetic pickup is just few kilo ohms). The preamp has to be able to tame the signal, and turn it to reasonable Z. Even if the preamp works fine, the recording interface should have a high impedance input. Usually the XLR input is for lo-Z signals like microphones. If the (jack) input has any switch for hi-Z input, use it.

[Beedster]

Some 90s MIJ Fenders had bridge piezo and split coil Precision PUPs and required a modification to make them playable, at least if you wanted to use both, there’s a thread on here somewhere 👍