TaelonOrigin wrote:

Hi! I just started my first foray into decent sound setups. I got a pair of Polk LSim 703s when they were on sale for 50% off (yay!) and picked up a cheap Sony DH550 receiver and an Aune T1 amp.

Here's my concern, I've been reading about all the dangers of underpowering speakers (apparently the DH550 only puts out 90 watts RMS), and I really couldn't afford to replace these, so i've kept the volume less than 50% on the reciever at all times (maxes out at 73, i've kept it 35 or less, is it even linear?).

Recently I was playing sound through my laptop/Aune t1 (connected to the sony throught the RCA line out), and I had the computer at max volume (which i've read you shouldn't do), this lead to some distortion from the source, even though the amp was only at 40-50%. Is this kind of "source clipping" capable of damaging speakers, even though the amp itself was kept at a moderate volume level?

TL;DR: Low volume amp + maxed out volume DAC input = damage?

Thanks!

You may have had the input voltage to the amplifier too high and overloaded the input circuit of the amplifier, which caused distortion. This is very unlikely to cause any damage to anything, but of course it will sound godawful. The computer may put out enough voltage to overload the amp input circuits if its volume is set too high.

With the amplifier at low to moderate volume, it is very unlikely that the amplifier was clipping, and in any case the speakers can probably handle anything the amp will put out when the volume control is set at 50%.

But the rule, always, is that when it sounds distorted, get the amplifier turned way down IMMEDIATELY!!! Be safe.

Volume controls are not linear, because to get significant volume increase you need very large power increase. Volume control potentiometers are logarithmic, not linear.

If your receiver has a numerical readout for "volume"(gain,really), rather than a manual knob, the numerical values may or not be linear, but probably not. The chances are that an amplifier gain of 35 represents less than one-fourth of the power you would get at an amplifier gain of 73 (for the same input voltage).

The actual output power does not depend only on that numerical value, however. That numerical value, the so-called "volume" setting, is actually only an indication of the amplifier GAIN; NOT power or volume.

The output POWER is a function of the amplifier gain times the input voltage to the amplifier. That is why you can set the gain to a certain value, 40 for example, and different sources will give different volume levels, because those sources often do not put out the same voltage.

When Stereophile tested your speakers, they found their sensitivity to be 88 db/watt/meter.

That means that 10 watts will drive them to put out 98 db, which is very loud.

Your receiver should have plenty of power to drive those speakers; there is certainly no problem there.

Your receiver's sound quality is probably not as good as a Marantz or NAD receiver, but that is another story entirely. It has very little to do with the rated power of the unit.