Sound Advice: Matching new receiver to vintage speakers

January 5, 2015

Q: I have some 1970s-vintage small Advent speakers. They are in great shape and rated at 15 watts RMS power handling. Iím in need of a new receiver to go with them as the old one died. How do the "old" power ratings compare to the "new," inflated, power ratings? I look and I see ratings of 100 watts per channel. I donít want to blow out the speakers.

óJ., address not given.

A: It is hard to compare "old" vs. "new" power ratings across the board because different brands rate different components in different ways. Separate power amplifiers tend to be rated accurately, even today, so you can compare power ratings and it is apples to apples. When you compare a 5.1-channel surround sound receiver to a seven channel amplifier you will see the receiver might say, "50 watts per channel with two channels driven," which means that when you drive all five channels simultaneously, the power output is significantly less. The separate amplifier will say, "75 watts per channel with all channels driven" which makes it a true 75 watts, all the time under all conditions.

You can use almost any amplifier or receiver with your speakers. The 15 watt rating does not have much real-world significance because there are very few amplifiers rated at 15 watts or less, and more importantly, you are more likely to destroy speakers with an amplifier with too little power, not too much.

For example, say you are playing music with your speakers and the average power needs is 4 watts. Suddenly, a crescendo kicks in and 40 watts are required. If you have a 15 watt amplifier, it will run out of power at 15 watts and start creating distortion, which will burn out speakers very quickly. If you had a 50 watt amplifier, the amplifier can reproduce the 40 watts cleanly and you will be fine 99.99999999999 percent of the time.

There are limits to this. You could not hook up a 1000 watt amplifier and use your tiny speakers to fill a concert hall with sound. Even with clean power, you would blow them out. But for most listeners and speakers in home situations, there is a saying in the audio world that "you canít have too much power."

The Onkyo TX-8020 I have recommended in the past is rated at 50 watts per channel and sells for $179. It is rated at 20 Hz-20 kHz with .08 percent THD with both channels driven, which is a conservative, real-world, "old" kind of a power rating, not an inflated rating. It would be a good match for your speakers, which are quite good despite their age.



Associated Press