Series parallel wiring with stacked Quad 57.

Positive from amp to positive of top Quad speaker. Negative of top Quad Speaker to positive of bottom Quad, negative of bottom Quad to negative of Amp.You require one long positive lead ,one long negative lead of equal length and one shorter jumper.Again the jumper goes from the upper Quad negative to the lower Quad positive. This is how to wire when you stack the Quads bottom to bottom so that the upper Quad is in the standard orientation and the Quad below it is inverted, (the top of bottom Quad is now at the bottom of the stack). This will make your amp see the same load as 1 pair of Quads 57.It worked for me.

Positive from amp to positive of top Quad speaker. Negative of top Quad Speaker to positive of bottom Quad, negative of bottom Quad to negative of Amp.You require one long positive lead ,one long negative lead of equal length and one shorter jumper.Again the jumper goes from the upper Quad negative to the lower Quad positive. This is how to wire when you stack the Quads bottom to bottom so that the upper Quad is in the standard orientation and the Quad below it is inverted, (the top of bottom Quad is now at the bottom of the stack). This will make your amp see the same load as 1 pair of Quads 57.It worked for me.