How much power needed to drive 91db speakers?


Sonus Farber lists the sensitivity of my speakers at 91 db SPL@ 1 meter @4 ohms.  They also say I should use  50-450 watts of power. My PS Audio amps pump out 500 watts @4ohms, so the max isn’t a problem, but if I switched to something 15-50 class A watts, would that be more than enough power?  
 

Thanks in advance.

curiousjim

Showing 6 responses by curiousjim

@kofibaffour 

I said class A watts.  I never mentioned Tubes.  But now that you mention it,  there’s an ARC 80S amplifier listed elsewhere that peaked my curiosity.😁 It uses 4KT 150’s and can put out 70 watts. 

@ghdprentice 

George,  I knew when I mentioned the Ref 80s that you’d chime in.😁

Do you have an older Amati model?  The G5 ( which I have) is 91 db, so that makes me agree with you even more about 70 watts being more than enough.  
Now to start working on the wife.

 Wish me luck.🤞🏻🤞🏻

@freediver 

Thank you!

That is incredible generous of you and I will definitely keep it in mind.

curiousjim ,I have a small Chinese made Pure Class A integrated amplifier that is based on the original Sugden A21..Puts out 15wpc.@8 ohms & can drive a 4 ohm speaker...
 I would be willing to let you borrow it any time as it’s just sitting in it’s box..You pay round trip shipping...Cheaper than buying & trying

I would like to thank everyone except @billstevenson for giving me intelligent and helpful answers.  I’m going to borrow a friend’s DVR that even though it class D, it’s rated at @75 watts per channel, so I should be able to get an idea.

@quincy 

Sorry.  Somehow I missed your post. Before the Sonus Farbers, I had a pair of KEF Reference 5’s and they were very dynamic.  Normally I don’t play loud, but the other day I played Tricycle by Flim & The BB’s for my wife.  Don’t know if you’re familiar with the tune, but it starts off with a piano playing and then it gets LOUD for a second and then goes back to the piano.  My amps are class A/B. The first 10 are A and Class B up to supposedly 600 at 4ohms. Other than having to scrape my wife off the ceiling everything sounded great.

Do you think your amps could handle the dynamic range when played loud?

Thanks.

@niodari 

See the post above I sent to @quincy . My amps are Class A for the first 10 watts and I rarely use all 10, but I’m sure I went wayyy above the 10 when I was playing tunes for my wife.😁 I might have hit 50 watts or I may have hit 300.  I didn’t check the dbs. Maybe I should have.

Out of curiosity, have you ever played Tricycle on your system?  If you do, keep the volume way down the first go round.