Recomended setups incompatibility

[admin_exported]

Reference nov 09 issue

Hi

At the start, page 6 to be exact, you tested Q Accoustics 2000 series speakers and paired them with a Sony STR DH800 AV receiver.

The output of the AV amp is 8 ohms and the speakers are 6 ohms.

Is this ok as I am lead to belive that if you use a speaker of lower impedance than the amp, the amp will be overworked and possibly damaged?

I have a STR DN1000 av amp, which is similar to the Sony STR DH800, and the impedance is 8 to 16 ohms, so I would like to know the answer as I want to get the Q Accoustics speakers.

 

[matthewpiano]

This will not cause you any problems at all.

 

[davejberry]

I agree. The Sony amps (as most other av amps i know) will work quite happily with 4 ohm speakers. You just can't use two sets of fronts, for this they must all be over 8 ohms. It explains this in the manual.

 

[Anonymous]

Thanks very much, both of you, for your replies.

I have read the manual from front to back but no mention of 2 sets of fronts, I suspect I can't do this anyway.

Rick

 

[Andrew Everard]

No, you can't. But this is a case of a manufacturer playing it safe, given that speaker impedance isn't fixed, but varies with frequency. A speaker with a nominal impedance of, say, 8 ohms, may have savage dips in impedance at certain frequencies, and lower impedance sucks power out of an amplifier so fast that the power supplies can't top them up again fast enough (that's the very rough version!).

That causes distortion, which can damage speakers: most amps have cut-outs which shut down output to prevent this damage happening.

The variation in impedance differs from speaker design to speaker design, but trust us - you can use the speakers we suggest with that amp.