Originally Posted By: eddie1261
[quote=RJ 1911]




What you are describing works with an additional passive pickup because all the pickups and controls are of similar impedance.

The piezo element itself cannot be mixed in with the humbuckes due the relatively low impedance of the humbucker circuitry (compared to the piezo element). As I mentioned, the humbucker circuit will load down the piezo element.

So a preamp or buffer is necessary. But if you try to mix the preamp output into the output jack through a volume control, you will now have the opposite problem. The preamp output is a very low impedance, and will load down the humbucker circuitry. In fact, it would practically kill the humbucker signal completely with the piezo volume at 10.

The Graph Tech preamp includes a two channel mixer, with the piezo signal on one channel, and the humbuckers on the other. Just like any mixer, each channel operates independantly of the others with no interaction.

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