Attenuation for piezo

[Tarzan]

Hi, Searched the web but couldn't find a simple document describing the how and why of an attenuator for piezo horns.
Schematic, formula and the like are welcome.
Use is for guitar and bas guitar cabinets up to 400 Watts.
Cheers,
Tarzan

 

[AndrewT]

Hi,
since the piezo is a very effective capacitor, you can use a series capacitor as an attenuating element. I don't know how well this works or how easy/difficult it is to get sounding right.
I have seen quite a few references to using a cap in lieu of a resistive L-pad.

 

[Tarzan]

Hi Andrew,
Yep that's what I've seen too.
But nobody seems to proof their findings with formula's and a reliable way to produce predictable results with different parameters.
Trial and error is a way, but I passed that stage.
Time is not on my side...
(Rolling Stones: http://www.youtube.com/watch?v=Ui1te79iEEw&feature=related)