Axiom Home Page Forums General Discussion Home Theater Onkyo 875

Drew, listening impressions not resulting from controlled double blind sessions with all variables held constant shouldn't be used as if they were established fact. The numbers in your post aren't realistic for listening to M80s at a typical distance in a typical listening room. For a 105dB peak level something on the order of 50-100 watts would be used. Also note than a 6dB difference per doubling of listening distance can't be accurately applied in a live room rather than an anechoic chamber. The difference would be far less, depending on room characteristics, but 3dB rather than 6dB would be closer as an estimate.

Like you said the distance are off, I am not measuring at 1M away, I am measuring at my listening position nearly 3M away, big difference as you noted.

A receiver being able to sound good upto its' limits has a lot more to do with the source than the amp itself. I find many CD's start to sound bad in that 95-100 db range in my room. I think I've been able to get Dire Straights-Brothers in Arms up to 106-107 before it starts to degrade, all this measured at my listening position ~9ft away.

I'm not sure what your results mean, but sitting 12ft from my speakers, my Denon 3300 can run in the low 100db range all day. Peaks can hit 107 or so, but it will run smooth vocals at 102 for hours. I don't know if that is 9 watts, or 99, but it is all you could need, aside from the benefits of additional headroom.

Similarly for the 1909 (90w), it should hit it's 90w at about 112 dB. From the 12' equivalence shown above, the 1909 should sound good up to maybe 102 dB? Just thought I'd chime in while dB/watt ratios were discussed (again ;o).

According to my calculations at 90w a pair of M80's would produce a maximum of about 117 db from 1 metre and a maximum of about 105 db from 12'.

I guess your calculations are wrong. I guess. Perhaps you didn't calcuate the room effect adding db to your calculation.