[andycsb]

Hi Guys,

Been hearing that tube watts are more "powerful" than solid state watts. In fact...it happened last week...oh these speakers are fine with 25 watts tubed. However with solid state...double that. I should know this after so many years in the hobby...but I really still do not. 

Is this true? How does it translate sonically and on clipping issues?

Thanks for your help.

[Wind Chaser]

No, tube watts are not more powerful than SS watts. A watt is watt. Tube amps have a tendency to clip more gracefully than SS, but clipping is still clipping and a watt is a watt no matter how you slice it.

[opnly bafld]

Frank Van Alstine commenting on his 35w/ch tube amp:

"..........interesting observation that the Ultravalve seems to play as cleanly and loudly as a typical 100W/Ch solid state amp,............"

http://www.audiocircle.com/index.php?topic=102226.20

[mresseguie]

You may get a hundred different answers to your question. I'll add my 2 bits:

I'd say that tube watts equal SS Class A watts. However, if you're comparing tube watts to Class A/B or Class D, I'd venture to say they're different.

Next!

[FullRangeMan]

No, tube watts are not more powerful than SS watts. A watt is watt. Tube amps have a tendency to clip more gracefully than SS, but clipping is still clipping and a watt is a watt no matter how you slice it.

With all due respect I will disagree.
W is just a mathematical calculation, its the result of Tension x Currrent.
So different proportions of Voltage X Current can result in an Watt final.

Example of different structures of a 30W figure:
Amp X 10V x 3Amp=30W
Amp Y 15V x 2Amp=30W
Amp Z 7.5V x 4Amp=30W

So W is an imaginary power figure that does not exist in the electrical reality, what exists circulating in the amps circuits and loudspeakers are different amounts of voltage and current.
Hope this help.

[fredgarvin]

With all due respect I will disagree.
W is just a mathematical calculation, its the result of Tension x Currrent.
So different proportions of Voltage X Current can result in an Watt final.

Example of different structures of a 30W figure:
Amp X 10V x 3Amp=30W
Amp Y 15V x 2Amp=30W
Amp Z 7.5V x 4Amp=30W

So W is an imaginary power figure that does not exist in the electrical reality, what exists circulating in the amps circuits and loudspeakers are different amounts of voltage and current.
Hope this help.

Good post, and at least with my guitar amps and others', a tube amp branded with identical wattage definitely sounds louder in a room than a SS amp, no doubt with exceptions. As for hifi I'm not sure.

[JohnR]

A tube watt is the same power as a sollid state watt. However tubes run hotter than solid state so their watts have a lot more warmth to them. This is why people sometimes get confused.

[Tyson]

A tube watt is the same power as a sollid state watt. However tubes run hotter than solid state so their watts have a lot more warmth to them. This is why people sometimes get confused.

[dB Cooper]

I'm sure this thread will settle the question much better than the 300 previous ones on this same topic.... 

[Elizabeth]

My problem with tube amps is the TUBES. They go bad, they explode and set your home on fire....
Then you gotta replace the tubes... and your home needs a refurb....

[Tyson]

My problem with tube amps is the TUBES. They go bad, they explode and set your home on fire....
Then you gotta replace the tubes... and your home needs a refurb....

True, tubes are more fussy than SS amps.  I find that they sound better, though.  Especially for Classical and acoustic based Jazz.  For electronic based Jazz and almost all Rock/Pop, SS amps draw even (and even sound better for many people). 

I listen to almost 100% classical, so tubes are my preference....

[Wind Chaser]

A tube watt is the same power as a sollid state watt. However tubes run hotter than solid state so their watts have a lot more warmth to them.

And that is why some people put a heating pad under their amp.

[Blu99Zoomer]

 

[bladesmith]

   hmmmmmm.....


 

[BobRex]

My problem with tube amps is the TUBES. They go bad, they explode and set your home on fire....
Then you gotta replace the tubes... and your home needs a refurb....

A tad hyperbolic, dontcha think?

[JLM]

To address the OP (in generalizations of course):

- Tube distort into even ordered harmonics which are more 'ear and speaker friendly' than solid state which distort in odd ordered harmonics, so users can tend to push them into distortion.

- Tube amps have poor damping compared to solid state amps, which bloats bass and give the impression of sounding louder.

- A given tube amp can synergize better with a given speaker and of course the opposite can be true too.

- Tube (and class A solid state) amps tend to have bigger power supplies per watt than other solid state amps, which helps them sound more powerful.

- In the discussion of watts are watts, it takes twice the power (watts) to sound half again as loud and ten times the power (watts) to sound twice as loud, so dB of gain is the pertinent criteria not watts.  So for instance, the difference between 35 and 40 watts cannot be heard (less than 1 dB difference).

[JohnR]

Tubes don't distort - amplifiers do.

[jsm71]

I'm no engineer and even when things are explained by those who are, I am lost.  I have enough education though to know a watt is a watt, period.

I have learned through experience that wattage and speaker efficiency are to be used for general guidance when making decisions about potential fit.  The way any speaker reacts to any amp needs to be tried.  If they are great dance partners, the music flows.  If not, all the watts in the world won't improve the sound.  More wattage does help drive through complex crossover designs or energize large panel speakers.

Experience has formed these beliefs for me (YMMV): 
   I've had more SS amps than tube, but I prefer tubes.  I've heard SS amps that sound exquisite, but I can't afford them.
   Tubes are indeed the most linear form of amplification and have the potential for the best sound.  Design can support or stunt that potential. 
   The higher output wattage tubes sound less musical to me - my opinion entirely.
   Iron core output transformers in most tube amps negatively impact a lot of the above potential.  Again, extreme money can overcome this.
   Power supply quality is a major contributor to dynamics and transparency - all types of amps. 
   Tube amps don't have to run super hot or suffer short tube life.  It's all about design.

[FullRangeMan]

I'm no engineer and even when things are explained by those who are, I am lost.  I have enough education though to know a watt is a watt, period.

   Tube amps don't have to run super hot or suffer short tube life.  It's all about design.

Please Note that W is a thing that only exists on paper, it is a virtual figure since it is the result of the multiplication of V x A as I said earlier, it dont exist circulating in the circuits, what circulates in the circuits are different proportions of Voltage or Current.

So Watts is like Gravity it is famous but it dont exists in the nature both are a consequence of something greater.
Tubes are indeed the most linear form of amplification and have the potential for the best sound.
Some tubes are linear other no, KT66 is suited to audio by its linearity for this guitarist dont use this tube, it cant be overdrived, already the original 300B nor bass had, it just has the mid range freq, but what a midrange!
   The higher output wattage tubes sound less musical to me - my opinion entirely.
   Iron core output transformers in most tube amps negatively impact a lot of the above potential.  Again, extreme money can overcome this.
   Power supply quality is a major contributor to dynamics and transparency - all types of amps.
Very correct, some transformers lamination are expensive as they are intended to use in fancy tube amp ((

[Docere]

Interesting discussion.

While a Watt is indeed a Watt, most solid state amplifiers are voltage sources (voltage stays essentially constant, current changes in response to speaker impedance variance with frequency) and valve amplifiers, especially those without global negative feedback, are power sources (voltage will vary in response to speaker impedance variance...). Voltage is (largely) responsible for acoustic output.

Most speakers will increase impedance at bass tuning frequency, driver resonant frequencies, and upper frequencies - power sources will increase the acoustic output (maybe noticeably) at these frequencies.

Valve amplifiers without global negative feedback have lower damping than amplifiers utilising feedback (solid state and class AB valve); unless a speaker is designed to specifically work with the lower damping factor, bass can be a little soft and elevated in acoustic output through the bass frequencies.

I agree with many of JLM assertions below. I would like to clarify the "poor" damping comment: output impedance is higher and needs to be taken into consideration, but it is not a case of good or poor - solid state amplifiers into some speakers can sound unnaturally "tight", constipated, and lean and tube amplifiers into some (many) speakers can sound soft and boomy. It is a case of matching, whether solid state or tube... but most speakers are designed for voltage sources not power sources, hence tube amps can be tougher to match.

Class A amplifiers - especially valve amplifiers - clip gracefully and may generate more acoustic output (for rated output) than expected before noticeable distortion.

IMO amplifiers comprise a modulated power supply and current loops. Many tube amp power supplies and current loops are poorly implemented... A good power supply goes a long way towards making an effortlessly powerful-sounding amp (within reason). Rare. I've calculated and modelled several popular designs - generally awful.

Finally, nice inexpensive valve amps exist, but powerful, dynamic valve amps cost; great valve amplifiers cost more. Solid state is more economical and can sound very nice indeed - I love(d) my Metaxas amps (when they worked)... but I prefer valves into suitable speakers: music is more humanly expressive.

Cheers!