Watts for speakers [Archive] - Audio & Video Forums


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10-18-2007, 07:14 AM
Is there some sort of formula to decide what speaker goes well with an amp? I have a 60 watt amp so I've been looking for front speakers. I keep hearing certain speakers are power hungry which is a term I don't even understand. So, I'm hesitant to purchase now because I really want to match my system well.

10-18-2007, 09:40 AM
With most modern speakers, you really don't need to worry about watts unless you play your music at +100dB's or are filling a gym. Consider that your average speaker has an efficiency rating of ~89dB/1w/1m. This means it is producing 89dB's of sound pressure (volume) when fed 1 watt measured 1 meter from the speaker. 89dB's is pretty freakin' loud...and that's with 1 watt!

What will trip up most amplifiers is a speaker's impedence which, loosely translated, is the resistance it presents to the amplifier. What gets most amps into trouble is a speaker that has either a very low impedence (measured in ohms) or presents wild swings in impedence throughout the spectrum. For example, the legendary Quad ESL was known for two things: 1) Incredible transparency throughout the midband, 2) Incredibly tough load characteristics with impedence that dropped below 1 ohm. You needed the current of an arc welder to properly drive the ESL (an exaggeration...kinda) That speaker was an amp killer of the highest order because unless your amp produced the current to keep up, it would either clip or melt it's rails.

For speakers that aren't panels or saddled with very low efficiency, 60 watts should be more than enough to reach sane levels of volume. Bottom line, I wouldn't worry about it.

What speakers are you considering and what do you use for an amp?

10-18-2007, 10:04 AM
I bought my Pioneer 5.1 reciever planning to use the speakers from my previous system. I hooked them up and it sounded great!!! Then I started to notice that my system was over heating. So I started doing some homework. My previous system used 4 ohm speakers while the Pioneer recommends 8 ohm ."with that said". I found some Sony 8 ohm speakers on sale at Bestbuy model# SS-B1000 125 watts for $40 a pair so I bought two pairs and made 1 pair my center speaker and the other my surround speakers. I had two 8ohm floor standing speakers from a couple of years back that I used for the two fronts. Now the over heating problem is gone completly and this system rocks. I would be more worried about the ohms than I would the watts so you don't blow your system up.

10-18-2007, 10:10 AM
it's a combination of alot of factors. And watts are merely a guidance. Modern speakers which are rated for 200 watts RMS will not actually take these all the time.