Originally Posted by n3rdling
I'm confused; how come sometimes I'll read about amps that are 100wpc that "can't drive x speakers", but then there will be some tiny 10 or 12wpc amp like this one that's driving inefficient speakers? Is that the advantage of T-amps? Would this amp be able to run a 4Ohm, 86dB loudspeaker?
A lot depends on the listener, speakers, average listening levels, source material, amplifier to speaker impedance compatibility, distance from speaker, etc. As long as the speakers' impedance are compatible with the amplifier though, any amp will be able to run them, the only question is how loud and if you like the sound. As for sound signature preference, can't help you there, but may be able to shed some light on loudness.
A general rule of thumb I use is to keep 18 dB of headroom over my average listening level. Why 18 dB? The vast majority of material keeps spikes below 12 dB, but an extra bit of headroom just in case something does and to giving the amp a little buffer isn't a bad idea. This can be adjusted as you see fit, though if you're want a system capable of reproducing to certain 1812 Overture recordings correctly, 40 dB or so of headroom is needed.
In a nearfield situation (~1 m from the speaker), maximum average listening volume is 82 dB. IMHO, this is enough for the usually less rigorous applications that call for nearfield speaker usage. (Computer, desktop, etc. usage)
In a listening room situation (~2-4 m from the speaker), maximum average listening volume is 76-79 dB. IMHO, this is questionable. I like to listen around the 85 dB range when listening for enjoyment. This setup wouldn't work for me as at 85 dB as I'd be chopping my headroom in half and risk amplifier clipping. But if you like listening at low levels, this may work.Assumptions and math for calculations above: Speaker sensitivity is 86 dB/Wm per speaker. Double that for pair, so assume 89 dB/Wm. Amplifier power is 12 WPC. Converted into dBW, is ~ 11 dBW. From that, full scale output is is ~ 100 dB at 1 meter. Also assuming that we want to keep 18 dB of headroom and assuming SPL drop of 3dB for every doubling of distance, referenced to 1 m.