Powering Old Infinity towers with Peachtree 125 sky-- with analog EQ

Running the loudspeakers in parallel might work but I'd be concerned about the low impedance at that point. Maybe call Peachtree?

"...Any suggestions?..."
"... I’ve always been an early RS Infinity guy..."

I use to stop by a little shop, Woodland Stereo, where Arnie Nudell and Walt Lewsadder worked on the original Servo Static loudspeaker. Walt and Arnie would do their best at blowing up every amplifier on the market and often succeeded.
Anyway, Infinitys love power, I’d try a Parasound A21. It’s got some guts and can drive that load.

P.S. I still run my RS1B woofer towers and my nephew has my RS2.5s