Ralph- I've been using a MacIntosh MC275 with a set of custom Quad 2805's- the chinese panels are not well made and I had Kent McCollum rebuild using UK-produced 63 panels, then add all his upgrades. Measurements on the Quad 63 & 2805 show 4 ohm as the low impedance. Measurements on the MC275 show good linearity and very low distortion (for a tube amp) when using a tap where the load equals or is higher than the tap utilized. While I originally ran the Quads at 8 ohms, I switched to the 4 ohm tap and it is very nice. I crossover at the appropriate point for the Quads and supplement the bottom with a Velodyne SW. The PA is a one-off SS design which is very clean and has almost nothing in the signal path- made by Ron Sutherland for me. Does the 4 ohm tap in this case make sense to you?
BTW, I have an unusual collection of ELS's including the original ML CLS pair. I don't mean one of the production models, I mean the original prototypes. Gayle Sanders voiced these to match a set of contemporary STAX ELS headphones as closely as possible. They really are spectacular but a difficult load to say the least. The production models were tamed down and never sounded as good at the original prototypes. Back in the day, I drove them with a Yamaha B-1, a rare beast that could handle very difficult loads and was quite an amp in the late 70's- all vertical Static Induction Transistors in the output stages. Speaking of Stax's, I also have a pair of 8x's- another superb and very rare electrostatic.
Gary Osoba
BTW, I have an unusual collection of ELS's including the original ML CLS pair. I don't mean one of the production models, I mean the original prototypes. Gayle Sanders voiced these to match a set of contemporary STAX ELS headphones as closely as possible. They really are spectacular but a difficult load to say the least. The production models were tamed down and never sounded as good at the original prototypes. Back in the day, I drove them with a Yamaha B-1, a rare beast that could handle very difficult loads and was quite an amp in the late 70's- all vertical Static Induction Transistors in the output stages. Speaking of Stax's, I also have a pair of 8x's- another superb and very rare electrostatic.
Gary Osoba