Can someone explain general sonic differences between the EL34, KT88, 300B, 2A3, 805, 845 in SET and PP configurations in terms of bass, midrange, highs, tonality, sound stage, dynamics, resolution, imaging, harmonics, etc. I'd be curious if there are references for the various output tube types?
Perhaps, the perfect amp would be a cross between a PP KT88 and a 300B SET based on observations. It seems difficult to strike a balance between lush, detailed, silky smooth mids, and airy highs, with a solid bass punch. I've often wondered if I should build a 6SN7 based preamp mated with a 300B SET amp crossed over for the mid/highs, and use a solid state amp crossed over for the bass...
Thanks
Perhaps, the perfect amp would be a cross between a PP KT88 and a 300B SET based on observations. It seems difficult to strike a balance between lush, detailed, silky smooth mids, and airy highs, with a solid bass punch. I've often wondered if I should build a 6SN7 based preamp mated with a 300B SET amp crossed over for the mid/highs, and use a solid state amp crossed over for the bass...
Thanks
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Yes, I'm, interested too. Please include the 45 and the 2A3 type tubes as well. Considerations for fixed bias vs. auto or cathode bias strategies would be appreciated. In the interest of fairness, please only compare designs with similar front end topolgies. Oh, and try to keep the responses to 200 words or less - I'm only interested in the facts.
Tubes themselves have no sound quality. Unfortunately the sentiment-driven audiofiles find this FACT difficult to grasp and hence continue to spread their ignorance-based nonsense.
Tubes actually have electrical characteristics, not sound quality. The characteristics must be manipulated by the designer to assemble an appropriate circuit. That circuit, when used in an appropriate system (including media, source, power supply, cables, amplification, transducers and listening environment), may be able to reproduce an encoded music signal such that the reproduction (by the SYSTEM) can be interpreted emotionally and hence (finally) subjectively labelled with a specific sound-quality.
So an inanimate tube (of whatever type) has no specific sound. Never has, and never will.
I doubt you'll find anyone who has all 14 of the amplifiers you cite, yet alone exemplary examples of each. And then to develop a subjective assessment of each amp based on 9 or more parameters becomes more than a lifes work.
But to think that there would be any consensus on the results......
I understand the desire to know and heck, if the book existed I'd pay $150+ for it!! You've obviously read a lot of threads on the different amps and so probably have the basis of an opinion yourself. Can you be a bit more focused in your question?
But to think that there would be any consensus on the results......
I understand the desire to know and heck, if the book existed I'd pay $150+ for it!! You've obviously read a lot of threads on the different amps and so probably have the basis of an opinion yourself. Can you be a bit more focused in your question?
ffs, with what transformers, if any? Resistive, inductive or CCS loaded? Driven by what tube, or indeed by a tube at all? At what voltage/current? Into what speakers, if any? From what source, ideal or otherwise?
They are tubes. They are made of glass and wire and have no majical properties. They regulate the flow of electrons more or less precisely to allow more or less current to flow in some hopefully proportional relationship to a signal. The only sonic difference with any relationship to just the tube is the sound they make when dropped to a concrete floor from a height of, say, 1.5 metres. The bigger ones go "Boom", the midsize ones "pop" and the very little ones "tinck". Sonically, the bigger ones are more satisfying, but you get more for your dollar from a smaller one.
I'm with Gordon - the question is so steeped in mysticism, preposterously unfocused, ambiguous and loaded, it faces a noisey and short death or eternal bickering.
Is there a new issue of audiophool magazine out perchance?
They are tubes. They are made of glass and wire and have no majical properties. They regulate the flow of electrons more or less precisely to allow more or less current to flow in some hopefully proportional relationship to a signal. The only sonic difference with any relationship to just the tube is the sound they make when dropped to a concrete floor from a height of, say, 1.5 metres. The bigger ones go "Boom", the midsize ones "pop" and the very little ones "tinck". Sonically, the bigger ones are more satisfying, but you get more for your dollar from a smaller one.
I'm with Gordon - the question is so steeped in mysticism, preposterously unfocused, ambiguous and loaded, it faces a noisey and short death or eternal bickering.
Is there a new issue of audiophool magazine out perchance?
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Actually while "tubes have no sound of their own," they do have transfer functions, which differ substantially from one type to another, and therefore in any given topology can be expected to sound different. (Neglecting GFB which would tend to minimize these differences, however I don't use feedback in any of my current designs. My older designs used it including in some cases nested feedback.)
To be valid an experiment would have to be performed such that all the tubes to be compared would be tested under similar conditions and with the same driver circuitry and OPT. Obviously given the differing electrical parameters of power tubes like rp, transconductance, plate and screen dissipation making a fair comparison could be difficult.
The question itself is far too broad to be reasonably answered, and a meaningful comparison would be difficult to impossible to make.. (Being cognizant of the differing parametric limitations of each type and the impact they would normally have on the design. )
My experience is that it is possible to build excellent amplifiers with any of the types listed. The output tubes are not the only determinant of the end result, and it is not easy to separate them from the balance of the design.
I like GM70, 300B, 45 and the 6550/KT88. I have no idea what they sound like individually as I compare amplifiers I have designed to each other. Probably my best overall so far are all based on the 300B.. (SE and PP)
To be valid an experiment would have to be performed such that all the tubes to be compared would be tested under similar conditions and with the same driver circuitry and OPT. Obviously given the differing electrical parameters of power tubes like rp, transconductance, plate and screen dissipation making a fair comparison could be difficult.
The question itself is far too broad to be reasonably answered, and a meaningful comparison would be difficult to impossible to make.. (Being cognizant of the differing parametric limitations of each type and the impact they would normally have on the design. )
My experience is that it is possible to build excellent amplifiers with any of the types listed. The output tubes are not the only determinant of the end result, and it is not easy to separate them from the balance of the design.
I like GM70, 300B, 45 and the 6550/KT88. I have no idea what they sound like individually as I compare amplifiers I have designed to each other. Probably my best overall so far are all based on the 300B.. (SE and PP)
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The sound of tubes
Picture tubes sound pretty cool. Sort of a "Whump" with a tinkly tail. The way I used to hear them was: place picture tube at rear of a refrigerator shipping box on it's side, screen facing the opening. Hurl burnt-up power transformer into center of screen. Whump! Well, I was 9 or 10 years old at the time
Also, Eimac tubes make a sort of hollow clanky ringing sound due to the bell-like suspension of the anode.
Picture tubes sound pretty cool. Sort of a "Whump" with a tinkly tail. The way I used to hear them was: place picture tube at rear of a refrigerator shipping box on it's side, screen facing the opening. Hurl burnt-up power transformer into center of screen. Whump! Well, I was 9 or 10 years old at the time
Also, Eimac tubes make a sort of hollow clanky ringing sound due to the bell-like suspension of the anode.
I did this experiment for a room full of people at the first VALVE conference, back in the 90's some time. I set up a driver stage and a SE output stage that could be configured to satisfy the needs of a variety of output tubes.
We worked up operating conditions that sounded best for each tube. I used a pair of Sowter 10K output transformers and ran them in parallel for the tubes that preferred a lower Z load. It worked out pretty well.
We compared a number to tubes from 45, 2a3, 300b, up to 211, 845 and some big Svetlanas. It was pretty easy to hear the difference. Sure, it wasn't a perfect comparison but I think a reasonable one.
We had some extra time at the end and compared different 211's and various operating points. It was fun. I let the audience make their own decisions about which tubes sounded best. In some cases the differences were fairly radical. Obviously this was with 1 driver stage, 1 output transformer and 1 speaker (Lowther). So that is both a plus and a minus. However, I think all the tubes we chose mated well to the environment.
I am not very good about verbally describing sounds (unless they are really bad!) so I will refrain from trying to differentiate your tubes. The best thing to do is try for yourself. It doesn't take much to lash up a prototyping board and some power supplies and swap the tubes around.
Excellent, this is exactly the sort of experiment I advocate! And it demonstrated clearly what we both knew to be true..
I have done some much smaller scale experiments with the same basic results. (Restricted to small 45/2A3/300B types in one test bed and EL34/6550/KT88 in another - not directly compared.) These tubes have differing transfer functions and in proper controlled experiments do sound and measure differently.
Sure they measure and sound different in any particular circuit, op point, load, etc., as they will also sound different and react differently to changes in op point, circuiit, load, etc.
But that's not to say you could ascribe the subjective impression of the sound to a set of tube parameters, for example, I believe the original question wanted an answer like this:
EL34
SET - Sweet midrange, airy highs, a little rolled off bass, slow dynamics, fair imaging but high voices blurred in soundstage
PP - Has bass punch lacking in SET but grainy midrange and dull highs, tight soundstage and good PRAT
KT88
SET - Plenty of bass punch, sweet midrange, clinical and cold highs, tight imaging, good dynamics, jumpy
PP - Loads of bass, somewhat scooped out midrange, outstanding dynamics, slightly blurry imaging, tizzy highs
300B
SET - clean and clear, outstanding resolution and imaging, excellent frequency balance, tight but unassuming bass, wide variation depending on manufacture. WE tend to be the best, new JJ are pretty good, the oversize "320XL" etc are very good also.
PP - good dynamics, powerful sounding, a little more veiled than SET 300B, produces a somewhat collapsed soundstage. clear neutral highs, unremarkable midrange
2A3
SET - clear and sweet at the same time, excellent soundstage, a little light on bass but honest at reasonable volumes, good frequency balance in mids and above, airy highs and clear mids. A little flowery in overall presentation.
PP - a lot like SE 2A3 but makes up for the lacking bass power of 2A3 SE. Soundstage a little collapsed as in 300B PP
805
SET - Painterly rendition of sound, like a Seurat or Van Gogh, very beautiful but certainly not neutral, yet authoritative at the same time, good bass punch and good balance of frequencies overall.
PP - very powerful and neutral sounding and somewhat etched, as is viewing a bas-relief. Highs are in your face but may be just the thing for vintage AR speakers
845
SET - Everest-like headroom in presentation, precise soundstage, and well-balanced frequencies. Harmonic structure similar to 300B and 2A3, but even more neutral.
PP - Effortless sounding, highly liquid and yet commanding in tone. lack of even harmonics to the point of being transistor-ey. a little over-emphasis on the mid-bass but could be great for woofer or a sub.
oddly enough, you will find that regardless of the tube, circuit or listener, none will be decribed as:
SET: mid-range honks like a canada goose in the mating season and wheezed like an emphasemic trombonist on crack from 5khz up. Bass bore a remarkable likeness to a fart from my 210lb mother in law.
PP: Similar to the SE, but twice as much of it and all in the odd-order harmonic.
They will all be, like the children of Woebegon Minnisota, "above average".
SET: mid-range honks like a canada goose in the mating season and wheezed like an emphasemic trombonist on crack from 5khz up. Bass bore a remarkable likeness to a fart from my 210lb mother in law.
PP: Similar to the SE, but twice as much of it and all in the odd-order harmonic.
They will all be, like the children of Woebegon Minnisota, "above average".
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As a recent member to the forum, my intentions for posting this question was not for the sake of sensationalism but mere curiosity, as I've only been learning about tubes for just 2 months. I have always been fascinated with vacuum tubes ever since studying radiology in medical & dental school, but never pursued it as a hobby. I am a fast learner, but there is so much more to learn I hope tubes will be around to make it a lifetime hobby.
I am sure that there are a lot of people, like myself, that don't have the expertise to control "electrical characteristics" to tailor a particular sonic signature from a given circuit topology. There in lies the art in the science. I can appreciate the fact that there are so many factors to consider as gordy, aardvarsh10, and kevinkr have pointed out, e.g., circuit implementation, PS, signal chain, cables, transducers, and even room acoustics, etc.
Perhaps, it's a philosophical question. If so, such a question will forever be shrouded in mysticism for many. However, all other things being equal in the signal chain, I was just curious if anyone has ever tried to demystify these tubes by testing the tubes I listed for their sonic character in a SET or PP design, or in any other circuit respective to a particular tube?
I am just trying to better understand the differences between one tube topology over another. I understand that a tube intrinsically does not impart a certain sonic character in itself, but why does one chose a 300B SET amp over say a PP KT88 mono block?... Or chose to substitute a KT88 over an EL34 for a particular sound?... One must have at least a generalized subjective view about a certain tube topology over another?... If "tubes have no sound of their own," why then have all kinds of different tubes with different circuit topologies?...
I hope, we are all human, and it's the music we're after, and not just manipulating electrical characteristics. It's impossible to not make statements or to not have feelings of the sound of one unit vs another. So then, let's listen and share what you hear... Who cares if there are 14 amps, with 14 different opinions, this is a forum after all, right?...
Thanks!
I am sure that there are a lot of people, like myself, that don't have the expertise to control "electrical characteristics" to tailor a particular sonic signature from a given circuit topology. There in lies the art in the science. I can appreciate the fact that there are so many factors to consider as gordy, aardvarsh10, and kevinkr have pointed out, e.g., circuit implementation, PS, signal chain, cables, transducers, and even room acoustics, etc.
Perhaps, it's a philosophical question. If so, such a question will forever be shrouded in mysticism for many. However, all other things being equal in the signal chain, I was just curious if anyone has ever tried to demystify these tubes by testing the tubes I listed for their sonic character in a SET or PP design, or in any other circuit respective to a particular tube?
I am just trying to better understand the differences between one tube topology over another. I understand that a tube intrinsically does not impart a certain sonic character in itself, but why does one chose a 300B SET amp over say a PP KT88 mono block?... Or chose to substitute a KT88 over an EL34 for a particular sound?... One must have at least a generalized subjective view about a certain tube topology over another?... If "tubes have no sound of their own," why then have all kinds of different tubes with different circuit topologies?...
I hope, we are all human, and it's the music we're after, and not just manipulating electrical characteristics. It's impossible to not make statements or to not have feelings of the sound of one unit vs another. So then, let's listen and share what you hear... Who cares if there are 14 amps, with 14 different opinions, this is a forum after all, right?...
Thanks!
Hmm, that sounds vaguely familiar.. I think I have heard an amplifier or two using that particular output tube at some point or other..
An interesting thread and some interesting responses.
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88man:
You are on the right track and yes, tubes will be around to keep you more than busy for an entire lifetime. I think that maybe you are underestimating the time and effort it takes to get a single amplifier design tweaked and tuned to the point where it is giving it's best.
From my experience the journey from concept to fit-for-consumption design release is over a year, possibly more if work, family & life get in the way. I don't think it's possible for a single person to fully explore all these variables in one lifetime. Anyone who says they have didn't fully optimize each design.
For a comparison to be be valid, all other variables must be held constant. I don't believe this can be done by one person. You need a team and then rigorous requirements to make sure you really are comparing apples to apples.
I think a better way is to read. then read some more. And then do some reading and perhaps build a few things. Then you will develop experience that will allow you to gauge the opinions you see on the different amps, built by different people, with different speakers and different rooms and different.....
At the end of the day, you never really know what warts are on a particular design, what compromises were made and where the skeletons lie so it's impossible to compare different peoples opinions of different amps. On the other hand, if you read 1500 threads and 500 of them say an EL34 in PP is the sweetest then that carries some statistical weight.
A noble, but I fear impossible, goal.
You are on the right track and yes, tubes will be around to keep you more than busy for an entire lifetime. I think that maybe you are underestimating the time and effort it takes to get a single amplifier design tweaked and tuned to the point where it is giving it's best.
From my experience the journey from concept to fit-for-consumption design release is over a year, possibly more if work, family & life get in the way. I don't think it's possible for a single person to fully explore all these variables in one lifetime. Anyone who says they have didn't fully optimize each design.
For a comparison to be be valid, all other variables must be held constant. I don't believe this can be done by one person. You need a team and then rigorous requirements to make sure you really are comparing apples to apples.
I think a better way is to read. then read some more. And then do some reading and perhaps build a few things. Then you will develop experience that will allow you to gauge the opinions you see on the different amps, built by different people, with different speakers and different rooms and different.....
At the end of the day, you never really know what warts are on a particular design, what compromises were made and where the skeletons lie so it's impossible to compare different peoples opinions of different amps. On the other hand, if you read 1500 threads and 500 of them say an EL34 in PP is the sweetest then that carries some statistical weight.
A noble, but I fear impossible, goal.
It can be useful to turn the question into "what do you want to hear". You. like all listeners, have your own "sonic signature". At it's most extreme, you may even have hearing deficiencies that make you prefer certain sounds to others. But within the normal range of hearing, listeners have their own priorities. Some are nuts on soundstage (or what they perceive as that), some want bass slam, some want detail (I can hear his watch tick with my new system...), some want transpararency, some want treble airiness, some want timbre.
A colleague of mine does recordings, and he wants soundstage - location of instruments in a mix. He has a whole vocabulary to describe soundstage, like the Inuit have 25 words for snow. I'm an ex pro musician who listens to a lot of classical music and my priority is timbre - pianos like a true Steinway, woody clarinets, shimmering cymbals etc. We disagree totally on what sounds good - we aren't even hearing the same things!
A purist might say "but a reproduction system must be accurate in all respects" - if we had such a system we wouldn't be writing on this forum. All hi-fi is compromise, so what can you live with and what can't you live without? I can't live without timbre and transparency so I just use DHTs right through - last used a 6SN7 years ago and wouldn't touch a KT88. But that's just me!! I don't bother at all with soundstage, and I'm indifferent to bass (I'm a bass player - the cobbler's children have no shoes.....).
To know what you want in a system, start by knowing yourself!
andy
A colleague of mine does recordings, and he wants soundstage - location of instruments in a mix. He has a whole vocabulary to describe soundstage, like the Inuit have 25 words for snow. I'm an ex pro musician who listens to a lot of classical music and my priority is timbre - pianos like a true Steinway, woody clarinets, shimmering cymbals etc. We disagree totally on what sounds good - we aren't even hearing the same things!
A purist might say "but a reproduction system must be accurate in all respects" - if we had such a system we wouldn't be writing on this forum. All hi-fi is compromise, so what can you live with and what can't you live without? I can't live without timbre and transparency so I just use DHTs right through - last used a 6SN7 years ago and wouldn't touch a KT88. But that's just me!! I don't bother at all with soundstage, and I'm indifferent to bass (I'm a bass player - the cobbler's children have no shoes.....).
To know what you want in a system, start by knowing yourself!
andy
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