Atma-sphere S-30 with Reference 3A?

If Sean wanted to stick with Atma-sphere would a Speltz transformer to raise the impedance be adviseable, or the S-30 just less than ideal for the DeCapo?

I've never used the Speltz autoformers and can't speak to their effect on output power with impedance changes.

However the previous statement "Raising the impedance will also reduce the amplifier's power output" is incorrect with Atma-Sphere amps.

In fact just the opposite is true. The S-30 outputs 45WPC into a 16 ohm load and 60WPC into a 30 ohm load.

I think an amp that might work well if there is a lot of impedance swings in the speaker would be the Pass XA30.5, which also happens to be one of the best amps I've ever heard with my Merlins, although If you believe Ralph Karsten (why woulnd't you?)all amps will work better into flat impedances, the higher the better. I don't if it is always true, but my impression is that speakers with impedance swings are best handled by SS amps.