Valves versus solid state

[Grey Owl]

Hi y'all,

Would someone please be able to explain to me, technically or in layman's language or both, why a 50 watt RMS valve amp sounds louder than a 50 watt RMS solid state amp?

Also, why does the valve amp sound more "authoritative"; that's not a technical term I know but it's the best way I can explain the feel and sound!

I've wondered this for years but never had somewhere to ask the question.

All views eagerly anticipated.

Cheers

[sine143]

I always *thought* that it was because Valve amps distort more organically (yeah, hows that for a sound term), so you can push them harder until you end up with square waves. prolly wrong though.

[Tom Smit]

Sorry, no square waves. However, I read somewhere that the reason valve amps sound louder is because of the distortion when pushed. A valve amp when pushed will have some distortion that is a pleasing sound whereas SS amps will sound nasty when pushed too far.

[sine143]

Sorry, no square waves. However, I read somewhere that the reason valve amps sound louder is because of the distortion when pushed. A valve amp when pushed will have some distortion that is a pleasing sound whereas SS amps will sound nasty when pushed too far.

when you push an amp to its limit its completely clipping. thus the result is a square wave.

[gilscales]

Are Tube Amps louder than solid state amps of the same power?
Yes and no. If you put a power meter on the output of a tube amplifier and a solid state amplifier that have been matched for total output power, then the meter will read almost exactly the same power for equivalent drive conditions - so in this sense, the answer is no, they are not louder.

However, if you LISTEN to the two amps, you'll find that the tube amp does indeed sound louder to your ears, in opposition to what the meter is telling you. Why?
It's tied up in the sensing instrument - that is, your ear. The way the human ear works is that it is very sensitive to the harmonic content of a sound. A tube amp is less linear (that is, has more distortion) at signal levels below clipping than a solid state amplifier.

The distortion will increase slowly, and then more rapidly as the amp starts to clip. In fact, the distortion increases so gradually and is of such a benign nature that the onset of audible distortion has no easily defined threshold. The solid state amplifier on the other hand has no such gradualism. It is almost perfectly non-distorting right up to the point that it clips, and then it clips HARD.  It's easy to hear the threshold.


This sudden onset of distortion is also composed of relatively harsh sounding distortion, not like the subtle second and third harmonics of the tube amp. The human ear hears the sudden harsh distortion as clipping and harshness. It interprets the low order distortion of the tube amp as a louder sound, not as distortion. In effect, the tube amp fools the ear into thinking that its early distortion is more loudness. They therefore sound louder or more powerful than the actual measurements show are really there.

[Bill Fitzmaurice]

Hi y'all,

Would someone please be able to explain to me, technically or in layman's language or both, why a 50 watt RMS valve amp sounds louder than a 50 watt RMS solid state amp?

Also, why does the valve amp sound more "authoritative"; that's not a technical term I know but it's the best way I can explain the feel and sound!

I've wondered this for years but never had somewhere to ask the question.

All views eagerly anticipated.

Cheers

When pushed hard tubes naturally compress the signal. You can achieve very much the same effect with SS and a high quality compressor, with tubes the compression is already there.

[Sydney]

Technically speaking tube and SS amplification is very different.
As stated: a lot of the sonic difference and preference between the 2 approaches are based upon how the designs perform when driven hard.
The variables often overlooked is that there are a huge number of ways of designing and implementing amplifiers: both tube and SS.
AudioXpress ( several years ago ) had a tube amp design specifically for guitar players that offered great flexibility in implementation for sonic "tailoring".
Like other aspects of audio: there are advocates for tube and often ( I believe ) summit articles that are intended to be objective; biased toward their personal preferences ( sometimes unintentionally ).
The 5/10 audioXpress issue has a very brief article:
About testing the differences between tube and solid state amps, in which the author uses oscilloscope plots. The article ONLY compares a modified Dynaco ST-35 against a LM3886 - Hardly a comprehensive analysis ( IMVHO, and I'm guessing written by a tube fan )

Syd

[Drey Chennells]

Are Tube Amps louder than solid state amps of the same power?
Yes and no. If you put a power meter on the output of a tube amplifier and a solid state amplifier that have been matched for total output power, then the meter will read almost exactly the same power for equivalent drive conditions - so in this sense, the answer is no, they are not louder.

However, if you LISTEN to the two amps, you'll find that the tube amp does indeed sound louder to your ears, in opposition to what the meter is telling you. Why?
It's tied up in the sensing instrument - that is, your ear. The way the human ear works is that it is very sensitive to the harmonic content of a sound. A tube amp is less linear (that is, has more distortion) at signal levels below clipping than a solid state amplifier.

The distortion will increase slowly, and then more rapidly as the amp starts to clip. In fact, the distortion increases so gradually and is of such a benign nature that the onset of audible distortion has no easily defined threshold. The solid state amplifier on the other hand has no such gradualism. It is almost perfectly non-distorting right up to the point that it clips, and then it clips HARD.  It's easy to hear the threshold.


This sudden onset of distortion is also composed of relatively harsh sounding distortion, not like the subtle second and third harmonics of the tube amp. The human ear hears the sudden harsh distortion as clipping and harshness. It interprets the low order distortion of the tube amp as a louder sound, not as distortion. In effect, the tube amp fools the ear into thinking that its early distortion is more loudness. They therefore sound louder or more powerful than the actual measurements show are really there.

Great explanation from the guy with what looks like a KT88? in his avatar..thanks gilscales.

I'd also say that tubes emphasize even order harmonics while transistors emphasize odd order
harmonics. The result is a smoother, more hi-fidelity sound. The ear
is much more sensitive to odd order harmonic distortion than even.
Also, tube amps way back would drive lower impedance loads than ss
as they had autoformers at the output.
I think it's safe to say that they also normally had much larger capacitors.. If the amp was driven to close to full power, while the power supply was trying to catch up on
those low notes, the caps can help supply the necessary power for transients.

I'm fortunate to have some great tube amps, Antique Sound Labs Monsoon 100watt monoblocks, driven by a Cary Audio slp98 f1 http://www.upscaleaudio.com/updates/slp98.htm. They push A. Gallo Ref 3.1 in my office system ( I spend a bit of time in there..; ).

[coolhandjjl]

I'd also say that tubes emphasize even order harmonics while transistors emphasize odd order
harmonics. The result is a smoother, more hi-fidelity sound. The ear
is much more sensitive to odd order harmonic distortion than even.

I'm into HiFi as well (but tube amps are out of my price range). In all the discussions threads I have read on the AudioKarma site, and the associated linked articles, the above seems to pretty much sum it up with one caveat. Some folks can't tell the difference. They become accounts. People with great hearing ability go into some sort of sound related field, people with great visual ability go into graphic arts, etc, etc.

[Sydney]

Uh-oh...
This smells like one of those "tube amps rule" discussions

Syd

[Bruce Weldy]

Uh-oh...
This smells like one of those "tube amps rule" discussions

Syd

When it concerns geetars.....they do!

[Grey Owl]

An excellent start to the day thankyou.

I feel the discussion is "warming up" towards tubes but there is a politeness in the air however, on the horizon, can anticipate a certain "edginess" approaching!

Nice to see that the gloves are still on gentlemen so am waiting for additional input (pun?) and maybe the definitive response.

Cheers

[LelandCrooks]

I have a early 60's Bogen 50w stereo tube amp for my home stereo. And a pair of pilot mono amps to be retubed one of these days to replace it. What I've found is anything recorded analog sounds better through it. Especially the old recordings made in the day, when tube amps were the shiznit. The ambiance and quality are fabulous.

New (late 80's and up), digital, sounds better through my solid state.

For my guitar, tubes, period. Ain't no substitute. Although I did like my peavey transtube quite a bit.

[Sydney]

I know guitarists/bassists that use(d) SS as far back as the 60's - though they are in a very small minority. Those that did/do use a much higher powered SS amp to prevent IM distortion.
Often they will use a tube pre-amp to get a "tube sound".
Since there are so many different ways to implement tubes and transistors, any declaration of superiority of one over the others is a proverbial apples to oranges comparison.
Lots of good and bad designs have been created in both tube and SS.
A class A amp sounds better than a class B or Class AB regardless of tube or SS implementation. There is a difference from a SS chip amp, a silicon power transistor, and a MOSFET device.
I have learned not to get between a guitarist and his sound.
The paradox of guys being willing to put up the downside of tubes ( inefficiency/weight/heat/tube replacement/ etc ) and yet fussing over the weight of the other elements of the sound systems is interesting. Not many willing to use an all tube PA ( at least not since the 60's )

Syd

[gilscales]

In my personal experience from back in my Oddiophile days as Bill would say (see before children!) I had personally owned several of the quality SS and tube amps over the years.

In the SS camp Bryston, Classe', Cello, Mark Levinson and in the Tube varieties Balanced Audio Technology, Manley, Audio Research, Cary, Golden Tube Audio.

Each had their specific strengths and weeknesses, overall my ears preferred the sound of tubes over SS as my last stereo set up consisted of the BAT electronics, the VK-5se, VK-D5se, 2 VK60's strapped to mono, Goldmund Studio Turntable and a pair of Ariel Acoustic 10T's

This system was MY holy grail and reference standard that I judged all other systems by for a few years and it was sad to part it out when the time came to give up the dedicated listening room but family is priority #1, we needed the room and the stereo was just a toy that was taking up space so... moved it into the living room where the MAGIC of the system was lost, that's when I decided to sell.