I am looking into building a Tubelab spp power amp. It delivers about 20 watts. I think the power is more than enough for my Martin Logans (I am using a 35 watt amp at the moment and never turn the volume up more than about 75 degrees), but I wonder if the varying impedance of the MLs would pose a problem.

The Martin Logan is a hybrid electrostatic speaker, mine uses a conventional woofer up to 500 hz and then the electrostatic panels for the rest. I have attached a graph of the impedance vs frequency. The yellow line is the impedance. The red line is phase.

Will the varying impedance cause any problems? If not which tap would I use on the OPT (my guess is that 4 ohm would be the closest).

Would I be better off just sticking to SS?

Thanks for any input on this.

The Martin Logan is a hybrid electrostatic speaker, mine uses a conventional woofer up to 500 hz and then the electrostatic panels for the rest. I have attached a graph of the impedance vs frequency. The yellow line is the impedance. The red line is phase.

Will the varying impedance cause any problems? If not which tap would I use on the OPT (my guess is that 4 ohm would be the closest).

Would I be better off just sticking to SS?

Thanks for any input on this.

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