Piezo splitting buffer board desing

Started by cags12, January 02, 2024, 04:29:45 AM

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Hi folks,

I have a Music Man Majesty guitar that comes with piezo saddles that connect to a summing board attached to the bridge block and then to a Music Man designed preamp.

I want to design and produce a replacement for the summing board that can take 6 piezo inputs, buffer them, and split the signals so the summed signal is still sent to the Music Man preamp board but I also have secondary 6 outputs of the independent piezos.

I know this is theoretically possible since this is the way the Graphtech hexpander works with the acoustiphonic.

I plan then to either incorporate an Autotune for guitar or the Hexpander system with the 6x string outputs.

I tried reversed engineering the Graphtech hexpander but it is a bit difficult to make sense of it.
Does any of you savvy's know of a basic circuit that can accomplish this?


I tried to do something like this when building my Hexstainocaster. Wanted to split and buffer the piezo outs to run both the Variax modeling and a hex to midi converter. RMC has a small board called the VAR001 that purports to do that. It didn't work for me. The hex to midi worked fine, but the sonics of the Variax side was suboptimal. But it might work for you and you could probably buy one and use it to reverse engineer something.
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I am familiar with your blog. Great reading.

Yeah I think the VAR001 is purely passive and possibly not able to fully isolate and buffer the signals properly. I am wanting to do it with proper opamps.

So far this is what I got from reverse engineering the GT Hexpander and reading over the internet