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Power output of tube amps compared to solid states

I'm having a hard time trying to figure out how tube amp power output relates to solid state power output. I've been looking at the classifieds for tube amps and I see lots of tube amps with 50w or 60w output, but nothing close to the 250w output typical of solid state amps.

So I have no idea what type of tube amp is required for my set up, right now I'm using totem forests with a required power rating of 150w-200w at 8ohms. The bass is so powerful on these that I have the sub crossover set to 40hz.

My question is, are tube amps so efficient that 50w from a tube sounds like 150w from a solid state? Or will 50w output from a tube severely limit how loud I can play my speakers? If so, are tubes usually meant to be driving super-high efficiency speakers?

I had previously tried a tube pre-amp with a solid state power amp (both musical fidelity) and didn't like the results because the imaging suffered greatly, even though the music sounded nicer from a distance. Now I want to try a solid state pre-amp (bryston) with a tube power amp (no idea which brand to look at), but I don't know how much power output I need or if it will even be possible with my speakers. Does anyone know what I would require?
acrossley

Showing 5 responses by marakanetz

marakanetz's avatar
marakanetz
5,473 posts
 
tubes have high output impedance so they need transformer to convert its output voltage into current to drive nowdays speakers. hence the power of tube amps become less 'visible' to the lower frequencies due to the transformer limitation. this yields that they sound louder per given power because they do not spend their power onto the subwoofer frequencies as solid states do.
other than that power can't be solid state or tube it's just a product of voltage and current.
marakanetz's avatar
marakanetz
5,473 posts
 
Atmasphere,
my due respect to your OTLs, they are money-no-object electronics for whoever can afford to spend extra $$$ for nearly twice larger amount of tubes per channel for the same desired output power vs. an amp with output transformer.

speaking of power compare in plain English, 100Wpc amp wouldn't 'reach' to 12" woofer... you wouldn't even see it's moving unless you crank the volume levels high; while 250Wpc amp would move the 12" woofer at the same sound pressure levels... so 4db also has diversified meaning towards full range.
marakanetz's avatar
marakanetz
5,473 posts
 
sorry for confusing, but i'm not speaking in terms of chaotic woofer movement. i'm speaking in terms of amount of pushed air from the woofer which is nothing else but sound.
marakanetz's avatar
marakanetz
5,473 posts
 
I also absolutely agree and even sure that larger drivers are easier to control since they don't need to be moved excessively by the voice coil to have the same SPL, but would they 'dive down' to its designed lowest frequency with 30W is a pure question of speaker design and type of driver.
My friend received Wyred4Sound ST1000 instead of traded-in Quicksilver M60 and the lower end difference, overall control and sound delivery is 100% towards Wyred4Sound driving Aerial 10T. This 'gentle giant' really pushes the air from Aerials!
If anybody wants to challenge S30 next to Wyred4Sound on the true full range speaker such as Aerial 10t drop me a note. I'll be more than happy to A/B it with anybody local or currently local to NYC.
marakanetz's avatar
marakanetz
5,473 posts
 
Arthur are you trying to say that at certain moment of time tube can throw let's say 1kw of transient power into the load??
Do you have any source that would graphically show measurements of the tube output transient response?
I have an access to the oscilloscope equipment and would be glad to be directed to test family of a transient responses of let's say popular EL34 tube.
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