The A275 is designed to drive multiple pairs of indoor or outdoor speakers from virtually any audio source. A typical installation consists of a home theater receiver zone 2 or zone 3 line level output feeding the A275. The A275 amplified outputs can drive speakers, volume controls, or ATON DLA speaker selectors depending upon the application. The advantage of using a DLA along with the A275 is the ability to drive multiple pairs of speakers while enjoying the benefits of the DLA selector; automatic impedance protection, dynamic volume level adjustment, discrete IR remote control, and RF remote control. The backbone of any distributed audio system is the amplification. The true test of any amplifier is the ability to drive multiple speakers at low impedance for hours on end. In this arena, the A275 excels! Heat is the number one cause for amplifier failure, or temporary audio loss from thermal shutdown protection circuitry, a.k.a. overheating. Of course that typically happens when you are entertaining a house full of guests. ATON designed the A275 with two long rows of external cooling fins to increase the heat dissipation. Higher cooling capacity equals longer product life and cleaner audio signal.