Michael, of course you aleady have amps in your 3805, and it's highly likely that they can provide more power than you need. Keep in mind that your M60s use about 1 watt for a comfortably loud average listening level at your listening position. Even momentary peaks aren't likely to require more than about 100 watts, which your 3805 handles with ease. Relax.

-----------------------------------

Enjoy the music, not the equipment.