erik_squires
The old McIntosh MX-100 tuner-preamp also had this function, although I don't know if it's included on more recent Mac products.
... no one has it because almost no one finds any value in it.Every Audio Research preamp I've ever seen has a phase inversion function. It can be very useful!
The old McIntosh MX-100 tuner-preamp also had this function, although I don't know if it's included on more recent Mac products.

