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WHAT'S THE DEAL WITH WATTS?

I'm considering acquiring a new (for me) integrated, under $2k, to drive my KEF full range speakers. They are very efficient (93db) , 4ohm and rated for 50 - 200 watts.  It seems that a good amp with 80 or 100 watts per channel at 8 ohms will take these speakers to any volume I'd want to experience in my medium sized living room.  So what advantage/benefit in sound am I going to get with 150 -200 watts, or more, per channel? Is it worth spending more for extra power that will never really be demanded?  
larstusor
lowrider57's avatar
lowrider57
5,417 posts
 
I should add that since your speaker's impedance goes as low as 3 to 4 ohms, an amp that doubles it's power rating would provide you with high current. For example, an amp rated at 100 wpc/8 ohms, 200 wpc/4 ohms.
The plus side of your KEF's is the high sensitivity of 93dB, so I would say you don't need to look for a high wattage SS amp.
You could also try tubes, although the reviews I've read are using SS.
mesch
3,524 posts
 
+1 Lowrider.  Look for a quality amp that doubles down in watts from 8 to 4 ohms. I run a BEL 1001 MK5. It is rated at 50 into 8ohms, 100 into 4, and 200 into 2. It will drive many speakers better than many 100 wpc amps will.  
paraneer's avatar
paraneer
818 posts
 
I’m considering acquiring a new (for me) integrated, under $2k, to drive my KEF full range speakers. They are very efficient (93db) , 4ohm and rated for 50 - 200 watts. It seems that a good amp with 80 or 100 watts per channel at 8 ohms will take these speakers to any volume I’d want...

I agree with others regarding an amp that can produce high current and preferably double down in its 4ohm power output. Or at least come close.

You know the speakers are 4ohm rated, yet you say that an amp that is rated 50-200 wpc into 8 will get the job done??? Not necessarily if the amp does not have its 4ohm specs published. It could have a compromised power supply and not be able to generate the current needed to be stable at 4ohms. Just make sure the amp has a 4ohm rating too and because the KEF’s have high sensitivity, you’ll have no problems. There are lot of good ones out there in your price range.

larstusor OP
59 posts
 
My bad; these speakers are rated for maximum 300w at 4 ohms. So an amp with 150w at 8 ohms which doubles down to 300w at 4 ohms would be most I should use. Correct?
xti16
1,525 posts
 
@larstosur In my experience you will get a little more 'control' of the music. By doubling the power does NOT equate doubling the max loudness. In general you will need 10X the power to double the loudness which is 3db. Our ears hear in a logarithmic curve not linear. But is that extra power worth it? You need to listen and make that decision yourself. From there there is many variables between different manufacturers. Most important would be 'current' reserves and how long can they be sustained especially for peaks. In most cases a few milliseconds is fine.
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