I'm looking at it from the viewpoint of someone with a driver in hand, wants to build a sealed box for a backchamber. The smaller the box, the higher the system Q for any particular amplifier output R.
Since lower driver Q comes with bigger motor, low Q drivers are more expensive. It would be rare to have too low a system Q, because it would mean the driver has too big a motor or the box is too big. In the early days, folks built big boxes and Small hadn't given us a filter based framework yet. Today, we plug a few numbers in and presto.
Since the Advent speaker, commercial stuff is often close to Q = 1.0 . Fortunately the Linkwitz transform gives us DIYers complete freedom now.
Much thanks, as always,
Chris
Since lower driver Q comes with bigger motor, low Q drivers are more expensive. It would be rare to have too low a system Q, because it would mean the driver has too big a motor or the box is too big. In the early days, folks built big boxes and Small hadn't given us a filter based framework yet. Today, we plug a few numbers in and presto.
Since the Advent speaker, commercial stuff is often close to Q = 1.0 . Fortunately the Linkwitz transform gives us DIYers complete freedom now.
Much thanks, as always,
Chris
I lived the transition from the tube to the transistor, and I regretted having got rid of my PP 6BQ5 by an Akai AA5810 (it was much nicer, that's true)
The solid state is unsurpassed in everything that means miniaturization needs.
Can you imagine a smartphone with tubes?
But in "true" high fidelity, forget it.
Still recognizing the great sound quality of Nad 3020.
The solid state is unsurpassed in everything that means miniaturization needs.
Can you imagine a smartphone with tubes?
But in "true" high fidelity, forget it.
Still recognizing the great sound quality of Nad 3020.
do not give up just yet....
was looking at your circuit and you want a 50 watt output? on a bridge tied load? did i read that right?
maybe we can ask a moderator to lock this thread and then you can open up a brand new thread with your schematics on post number 1, further is suggest that lay down parameters, like your desired gain, input impedance, etc..
4P1L is a very fine tube, two those in parallel is like a 2A3...
4P1L is a very fine tube, two those in parallel is like a 2A3...
It is not so simple.
Physical laws are immutable.
Large cabinets with large speakers equals less distortion because you move as much air as possible into the space without distortion, the differences with a small speaker are too large to try to compensate for with EQ, DSP, etc.
It's Hoffman's Iron Law
Why?
This has become one of the most interesting discussions I have followed in many years, and is "right on the money" relative to the subject in hand.
I had a highly muscular debate on exactly this area only a week ago with a constructor who bases his entire strategy on this very topic, inc forcing the ss PSU into a quite ridiculous 150 000 FARAD (you read right!) super condensor pile to supply it with "stable power".
We get to such a point of no return it appears! 🙄
I did suggest he could use it better for welding rails together for the national railway system!
Ah ah distortion, distortion, what is this distortion?
( and the molecules of "air" don't move but pass the motion from one to the others )
What is the damage that a large membrane do ? Is the magnitude of bass in the room the only measure for high fidelity? I see most of the people spend much part of speaker design in big bass design and are carried in the sector of resonance, Q, group delay and angle of radiation but the final goal which is -what arrives at your ears, can you identify which instrument plays correctly in space ( time is assumed to be right...you know...you press Play and...) and does it sound clear, live ?
Does a tube amplifier do that more correctly than a transistor/mosfet amplifier?
Why? Is it a merit of the OT or is the whole? And why tubes are not good in the line stage?
( and the molecules of "air" don't move but pass the motion from one to the others )
What is the damage that a large membrane do ? Is the magnitude of bass in the room the only measure for high fidelity? I see most of the people spend much part of speaker design in big bass design and are carried in the sector of resonance, Q, group delay and angle of radiation but the final goal which is -what arrives at your ears, can you identify which instrument plays correctly in space ( time is assumed to be right...you know...you press Play and...) and does it sound clear, live ?
Does a tube amplifier do that more correctly than a transistor/mosfet amplifier?
Why? Is it a merit of the OT or is the whole? And why tubes are not good in the line stage?
Totally agree with that, hence why I designed and built my own,- 235L no less.
That's 8.3cuft.
I have never heard anything else like it.
Absolute clarity esp for organ music or reggae, or even Rammstein!
We can even use it to test studio mics, -and were astonished to find they distort.
Hoffman was right, and I have one of his speakers to prove it.
Answer to those, YES & YES, but the vast majority of commercial tube amps can't, so back to good old - generalisations not possible.
Not to forget Schroeder again, bass frequencies are not directional but have localisation problems (nodes).
Above Schroeder freq, it's another whole story, tremendously relevant to this topic, because the HD800 CAN'T tackle the area which is the most critical.
Swop words "DO" for "CAN", and it's closer to the truth.
I'll be brave and offer an intuitive guess as to why 'kitty doesnt hear any "euphoria" from the tube at the center of those schematics; in being surrounded by op-amps, ideal current and voltages sources, anything the tube "has to say" has been linearized away by all the ideal-alities of the supporting circuitry.
It's similar to putting a tube in the feedback path of an op-amp. Op amp says "I'm going to keep the difference between my +/- inputs zero - no matter what. As long as it's within reach of my output's capability, stick anything in there you want and I'll overcome the obstacle. So put a tube there and the op-amp will make it - and it's sound - disappear. I'd venture to say it'll sound more like the straight up op-amp - morso than the tube.
I'll stick my neck even further. I'd say the euphoria (for lack of better term) from tubes comes from their being used in the classic manner, surrounded only by cleverly arranged passive components. The more we idealize the circuit (as in let's see...OK, replace this high value resistor with an ideal current source...) the more you strip out the tubes original voice, replacing that with something else. When every terminal of the tube is now being fed by some idealized technologically modern wonder-circuit, just get rid of the tube all together and make the whole amp without it.
I'll stick it out even further. The smart designers know when to stop with the ideal padding, knows how to artfully balance SS integration with tubes and particularly, knows when the addition of such is going to kill the [subjective term] or at least drive the design's sound into that other best we can come up with word, clinical. Which I take as the opposite of euphoria. I believe there's folks here (who've been suspiciously quiet) who can do this successfully and, it aint me babe. I'd have to start from the beginning and devote a whole lifetime to seeing, listening and coming to know just what does what in the context of tube amplifier circuit design.
So tubes do have a sound, but you can linearize that right out of existence via the supporting circuitry. I'm sure with today's SS tech, someone could take the plate current of an SE output tube and just multiply it (with a clever arrangement of modern, active components) to sufficient level to drive a speaker. OPT - and whatever it has to say in, on, through the music - eliminated.
It's similar to putting a tube in the feedback path of an op-amp. Op amp says "I'm going to keep the difference between my +/- inputs zero - no matter what. As long as it's within reach of my output's capability, stick anything in there you want and I'll overcome the obstacle. So put a tube there and the op-amp will make it - and it's sound - disappear. I'd venture to say it'll sound more like the straight up op-amp - morso than the tube.
I'll stick my neck even further. I'd say the euphoria (for lack of better term) from tubes comes from their being used in the classic manner, surrounded only by cleverly arranged passive components. The more we idealize the circuit (as in let's see...OK, replace this high value resistor with an ideal current source...) the more you strip out the tubes original voice, replacing that with something else. When every terminal of the tube is now being fed by some idealized technologically modern wonder-circuit, just get rid of the tube all together and make the whole amp without it.
I'll stick it out even further. The smart designers know when to stop with the ideal padding, knows how to artfully balance SS integration with tubes and particularly, knows when the addition of such is going to kill the [subjective term] or at least drive the design's sound into that other best we can come up with word, clinical. Which I take as the opposite of euphoria. I believe there's folks here (who've been suspiciously quiet) who can do this successfully and, it aint me babe. I'd have to start from the beginning and devote a whole lifetime to seeing, listening and coming to know just what does what in the context of tube amplifier circuit design.
So tubes do have a sound, but you can linearize that right out of existence via the supporting circuitry. I'm sure with today's SS tech, someone could take the plate current of an SE output tube and just multiply it (with a clever arrangement of modern, active components) to sufficient level to drive a speaker. OPT - and whatever it has to say in, on, through the music - eliminated.
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There are no opamps in the effective signal path of those schematics. Certainly not in the way you describe. Well, except for the sandman circuit of course.
Also I said I tried to make the tubes distort using passive components as you say to get the euphony but they just sounded worse. At least in the circuits I used.
Also I said I tried to make the tubes distort using passive components as you say to get the euphony but they just sounded worse. At least in the circuits I used.
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This appears to be a much more fascinating topic than examining the two mysteriously phase shifted sinewaves at the output of an amplifier. The technical challenges behind such a PS seem enormous. Can your friend be persuaded to start a thread on this? Or perhaps you can post a link?
Classic misdirection, giving us two choices as if only one can possibly be correct. I don't think you really believe this, it is just your debating technique and so far I see it going nowhere, why else do you just keep repeating it, don't you think it's time to move on and provide more relevant evidence for meaningful discussion?
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Hey, I did design my speakers and eventually managed to have a tube amp in my system! The speakers have a tiny 4 " ( and a half 😎 ) woofer, a 2" midrange and a tiny tweeter. Never experienced something like that. With a properly cut & geometrically valid cover of numerous pieces of felt, they virtually disappear.
Who is closer to the truth?!
🙄
( of course the setup is all analogue, because.....)
Why?
This has become one of the most interesting discussions I have followed in many years, and is "right on the money" relative to the subject in hand.
I had a highly muscular debate on exactly this area only a week ago with a constructor who bases his entire strategy on this very topic, inc forcing the ss PSU into a quite ridiculous 150 000 FARAD (you read right!) super condensor pile to supply it with "stable power".
We get to such a point of no return it appears! 🙄
I did suggest he could use it better for welding rails together for the national railway system!
interesting alright, but frustrating too..i thought a fresh start with the set of schematics would be a way forward...it will be more focused that way...
hey this is DIY and we are allowed by limitations of skill and money to get as crazy as we can as long as we do not harm ourselves...
and i agree 150 000 FARAD is way too much, he must own the factory making those caps and i envy him....😀
as there are no forum rules against stupid, we can only do so much...
like we can bring the horse to the water, but if the horse did not want to drink, what more can we do?
people with economic agenda do this...
that is why i suggest that Diyaudio come up with a rule that everything that is voluntarily contributed here should be a copyright property of this board..
no problem if you want to call a tube, "super triode:, but to claim copyright is another matter...
you can fool some people some of the time, but fool all the people all the time is something else...
what is beyond triode? another triode maybe, or transformer even.....
you can fool some people some of the time, but fool all the people all the time is something else...
what is beyond triode? another triode maybe, or transformer even.....
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note some thread number references may now be wrong as some rule breaking posts and collateral have been deleted. - Status
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