To the OP. Are you hearing problems or issues with your system ? These transformers are made as band aids to help with the amplifier / speaker interface, when impedance issues are present. McIntosh is the only ss amp company making autoformers as part of their design.+1 on this.
Thanks mrdecibel! No, not hearing any problems/issues. Always looking for the best possible soundYour PSA amps are perfectly capable of driving the ML’s without breaking a sweat, especially because the ML’s have their own bass amp, you will only go backwards putting an Autoforformer between them and your PSA amps, I have tried them on my ML based system and the Autoformer’s sounded limp and soft compared to without.
As Mr D said, the Autoformers can provide a "band-aid" solution for amps that can’t or have trouble with a speakers impedance load, but your better off saving the money as Autoformers aren’t cheap, sell the amp, and get an amp that will be happy driving the speaker.
Cheers George