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How many watts??

If I have a 80 watt stereo amp and I normally listen at quarter volume and never play at levels higher than this. Do I really need 80 watts could I use a 15 watt amp at half volume?

My next question if I have speakers that my mfg states needs min 50 watts to really make them sound good with my current amp rated at 80 watts but played at qtr volume does that mean I am not really getting the best from these speakers. If I play at half volume this is too loud, do I need a bigger room. Sorry if I did not explain clearly enough.


ecpninja
jasonbourne52's avatar
jasonbourne52
2,863 posts
 
The rule of thumb is: 10 times the average power in watts to avoid clipping. So with 80 watts you can use 8 watts average. That 8 watts into a 90 db sensitivity speaker will produce about 99 db continuously - if you can stand to listen that loud!
jasonbourne52's avatar
jasonbourne52
2,863 posts
 
Matching the wattage to the speaker sensitivity is important! You wouldn't want to drive Magneplanars with a 3.5 watt SET tube amp!
jasonbourne52's avatar
jasonbourne52
2,863 posts
 
Nor a Klipschorn with a 200 wpc amp!
holmz's avatar
holmz
2,328 posts
 
If I have a 80 watt stereo amp and I normally listen at quarter volume and never play at levels higher than this. Do I really need 80 watts could I use a 15 watt amp at half volume?

My next question if I have speakers that my mfg states needs min 50 watts to really make them sound good with my current amp rated at 80 watts but played at qtr volume does that mean I am not really getting the best from these speakers. If I play at half volume this is too loud, do I need a bigger room. Sorry if I did not explain clearly enough.
An oscilloscope might tell you what the maximum voltage is you are presenting to the speakers. Once you know that, then you could make an objective decision.

Or just hook up your amp and subjectively determine if it sound good to you.
ghdprentice
6,969 posts
 
In general more power is better. Watts are relatively meaningless if you desire good quality sound. Lots of current is a better indicator. If an amp, say, doubles the wattage with decreasing impedance it is a high current amplifier. But basically the higher quality the amplifier the better they sound. There are different designs that sound somewhat different. 
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