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
Ralph, I just might do that. It's a smallish room - I don't imagine that you have a quietized water cooling system perfected yet?
Acrossley; Just to chime in, power is power period. and power is defined as IxIxR or VxV/R or VxI. In any case, power is related to resistance only. But speaker loads are not only made up by resistance only but what is called impedance that includes resistive loads and inductive loads and capacitive loads. So, when you see an amp spec'd at 50 wpc into 8 ohms, the manufacturer is stating clearly that this amp will produce 50 wpc from a particular input voltage (input sensitivity) into an 8 ohm resistive load. If they wanted to be clearer they would tell you what the power output is into an impedance (R+L+C) load at particular frequencies. but they will not do that. So, basically, what is on the amp specs is not what is really happening because your speakers are not resistive loads. So you are comparing apples to oranges. another example would be to take two 50 wpc into 8 ohm amps. One tubed and one ss. They both have a particular input sensitivity which will drive an 8 ohm resistive load at 50 wpc and typically that is measured with an input signal of 1khz. But, make that load a reactive (resistive, inductive and capacitive) load at 1khz at the same input signal level and you have an entirely different story. Or lower or increase the frequency with the same input signal level and no way will you see 50 wpc, unless you have a very well designed and built amp and let me tell you, you will pay a lot for that amp. Because it was designed and built correctly. I hope I didn't glaze your eyes. but every 50 wpc rated amp cannot drive the same loads the same because they were not designed to. The specs presented do not tell you everything. But, my point (long as it is) is that 50 wpc into 8 ohms resistive is the same, no matter what amp we are talking about. But the real loads your amps see are definitely not resistive and therefore the 50 wpc into 8 ohm spec goes out the window.

enjoy
Br3098, I appreciate the humor but seriously, the heat of our amps is quite manageable. Up here in Minnesota we see the highest dewpoints recorded anywhere worldwide and our amps are easy to live with even in the summer. However the heat comes from being class A, not the number of tubes. You can run the amp in Standby all day and at the end of the day, put your hand on the tubes without fear of burns. But from stone cold, within a minute the tubes are way too hot to touch because they are conducting.

IOW a solid state amp of the same power that is also class A will heat up your room in much the same way- it will make about 85% of the same heat. The real issue is, what do you want the system to sound like? Real music? If so, you are going to have to go class A- all other classes of operation are performance compromises.

Now it may be that you can find nice-sounding amps that are not class A, in fact they abound. But the very best, the ones that stand apart- they will be class A.
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.
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.