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Help me spec n class A AMP, power calculation 85dB @ 1W @ 1metre

I was playing few pieces and recoding dB levels on my phone. After playing few tracks I see some parts of music sustains at 88db and peaks at 96db. I do like to hear music at this level for short periods of time. 

I am using the following calculator: https://geoffthegreygeek.com/calculator-amp-speaker-spl/

Sitting at 10 feet away from speakers I see the following numbers:

Assumption amplifier headroom of 1.5 dB, 10 feet distance

For 88db 1 Watt + 14.2 dB requires an amplifier power of 26 Watts
For 96db 1 Watt + 22.2 dB requires an amplifier power of 165 Watts

For 102db (room SPL losses) 1 Watt + 28.2 dB requires an amplifier power of 658 Watts (Ridiculous?)

It would be great if I can go get a class A mono blocks that can do sustained 200 Watts for each speaker @ 8ohm/6ohm and call it day but I got no dough for that.

How do I spec for a good amp(and may be integrated). I would like something that can sustain 35-50 Watts for class A and have reserves for peak of 200 Watts.

geek101
luxmancl38
580 posts
 
I would look for a Threshold T-200. 100 wpc Class A. A great space heater. I have a pair of T-50's that I purchased of a former Threshold employee. They were modified at Threshold to run as 100 wpc mono blocks. Michael Bladalius did the modification. These amps run hot and look at your electric bill.
d2girls's avatar
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d2girls
1,029 posts
 
Pass Labs XA30.8, or (budget willing) XA60.8 monoblocks are just what the doctor ordered. 
geek101 OP
284 posts
 
XA60.8 seems to be capped at 60 Watts. Am I missing something?.
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d2girls's avatar
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d2girls
1,029 posts
 
@geek101 yes you are missing something. you talk about "200w reserves" like you meant the amp is able to pull out an extra 200w if needed. I honestly assumed you were referring to amps that run class a for the first 10/20/30/50w or whatever, and transition to AB above that. If that is what you are speaking of (the way you formatted your post would lead one to believe this) then yes, the 60.8 can handle the peaks you're asking of.

if, however you were meaning you want all 200w of that power of class a and "in reserve" well sorry but no class a amp is going to be in a "reserve" state, its going to run hot, it's going to be heavy and it's going to be outputting a lot of power at all times. 

The only amps off the top of my head that offer up 200w in class a are Pass Labs, and Krell. There's plenty of others but most of them are in the 5 figure range. 
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