The Amplifier failing is the lest of your problems, since the speakers are
being grossly underpowered it will cause the amp to clip, especially when
producing loud (dynamic) bursts.

You will eventually damage the speakers!

NOT leaving the amp running for long durations and cooling it is a waste of
time. The amp will not be damaged but again, your speakers will.



"Leadfoot" wrote in message
news:TyCSa.13944$u51.11838@fed1read05...

The receiver is a Sony STR-DE685, the manual doesn't says anything
about
speaker impedance except in the rear view of the receiver where is a
label
below the speaker connectors that says to use 8-16 Ohms speakers.



I ran a Sony @100WPC STR-DE575 running 4 ohm Cerwin-Vega RE-30's for at
least 6 months. Mostly I used them for Home theather and some music and
rarely cranked them I recently upgraded to a Yamaha RX-V630 that while
rated @80WPC is much louder than the Sony. Part of the reason for the
upgrade to the Yamaha was the 4 ohm/8 ohm switch.

I don't think the 6 ohm speaker will pose a problem so long as you don't
crank up the volume for LONG periods of time and you make sure the Sony's
air vents are kept open. If you have a situation where you do want to
crank
the volume for long periods of time you could place a fan near the air
vents
to keep the air in the receiver circulating.