2-9-16 Back in 2014, when I first hooked up my newly re-foamed AR-9s, I had plenty (6) PL400s to try the ‘bi-amp’ configuration. Having never heard AR-9s in my home before, I was very excited that I could actually ‘bi-amp’, something I  had read about often but never tried before.  I didn’t get the pleasure I was seeking because one of the aging amps failed in a few days, then another failed, then another. Consequently, I have given up until I get those old amps rebuilt, whic