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Watts are watts?

So it's been said that tube watts aren't the same as SS watts. This always struck me as nonsense, but I'm open to hearing what others think. In particular, I've been wanting to delve into tubes...whether in the form of a tube preamp or a tube or hybrid integrated. So....I'm sure that 90 watts would easily drive my Goldenear Tritons 1s. But how about if I decided to return to Maggies? I would normally never even consider that little power for Maggies...hence the question. Are tube watts really "stronger" than SS watts?
secretguy
celander's avatar
celander
1,503 posts
 
@roberjerman yes, they were set up in a big room. How are your woofer surrounds? I got another set of DQ-10’s off eBay a few years back. The woofers were the first things to go. The legacy company was (is?) still in business, so I was able to get new woofers. 
erik_squires
16,138 posts
 
What’s missing in watts is the output impedance of the amplifiers. This can behave in positive or negative ways depending on the speaker and it’s design.

Also, its important to understand how little watts have to do with loudness. Relatively. Doubling the power increases loudness only by 3 db. To get double the loudness, you need 10x the power. So the difference between 90 watts and 150 watts is less than 3 dB.

If you want to do the math yourself: 

change in dB = 10 x log ( powerA / powerB )


Best,

E
geoffkait's avatar
geoffkait
23,365 posts
 
Good point! It’s the efficiency of the speakers. That’s why you only need 3 watts or whatever to drive horn speakers. Hopefully tube watts.
don_c55
1,025 posts
 
I powered my magnepan IIIa speakers with an Audio Research D125 (115 w/ch) tube amp for years with great results!

They played clear and very loud.
handymann
383 posts
 
IMO, there’s no substitute for class A bias output, whether it be tubes or SS.  Think of a class b amp as a dragster idling at the start line and a class a biased amp reved up to 8K rpm. The flag drops. The idling car driver, then puts the throttle to the floor and can go quite fast, however, the car that was reved up to 8K rpm simply drops the clutch and is gone in a flash.  May be a weird comparison, but the class a amp is always wide open sitting there just waiting for a signal.  It’s very quick.  No pause or sluggishness to reproduce that cymbal, snare crack or bass drum.  You can heat your room with them in the winter, but oh what sound.
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