Let me tell you that that sounds like a simplification, I was born with tubes, then the transistor arose and the whole technological world of audio said that "a dead king, put king", and it turns out that it was not so, I regretted having believed that .
So I went back to my "first love", not for a nostalgic question, but for an empirical certainty.
One thing is the solid state for computers and smartphones, an impressive and indisputable technological advance because it allows miniaturization, and another thing is the "old" tubes, unparalleled to enjoy music in its closest to the original state, in other words, a feeling of realism.
Try the following, attach an SS amp to a great pair of acoustic cabinets and then do it the other way around, a tube amp with a pair of mid-range cabinets. The second option wins by a large difference.
I've done it, I had a pair of Karlsons with 12 "RE speakers coupled to a DIY PP amp with 6BQ5 and was very happy.
Then I traded everything in for a pair of 14 "coaxial JBLs and a Japanese solid state amp ....
And there I was totally disappointed. What happened to the feeling of realism, to the dynamics? If I turned up the volume, the distortion was increased so much !! (call it harmonic distortion, or intermodulation distortion, it does not matter) Currently I went back to a tube amp, PP with KT88, and DIY cabinets and I am happy again.
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Let me tell you that you totally misunderstood my comment which was meant to counter the earlier argument that "you can't have harmonic distortion without intermodulation distortion, which isn't pleasing". Since there are many who like both NOS-DACs and tube amps it should be evident that moderate levels of IMD are not that unpleasent. And I have built several tube amps and even NOS-DACs to appreciate their sound. What I find a rather silly is to simplify "tube sound" to be only about high levels of HD (or IMD).
Tubes are inherently more linear than transistors
(yes there are exceptions)
So tubes need less correction by negative feedback
Negative feedback is disliked for it robs the sound of its musicality
Feedback on steady signal works great
But music is complex very dynamic signal full of impulses
Feedback takes some time to correct the input
This creates temporary large intermodulation distortion on those spiky attacks
And fatigue settles
You can create good and bad sounding circuits with both, tubes or transistors
But most of the solid state line stages I compared to tube line stages were clean, low distortion, but cold and heartless, while tube line stages were musical, yet both camps were low distortion
(yes there are exceptions)
So tubes need less correction by negative feedback
Negative feedback is disliked for it robs the sound of its musicality
Feedback on steady signal works great
But music is complex very dynamic signal full of impulses
Feedback takes some time to correct the input
This creates temporary large intermodulation distortion on those spiky attacks
And fatigue settles
You can create good and bad sounding circuits with both, tubes or transistors
But most of the solid state line stages I compared to tube line stages were clean, low distortion, but cold and heartless, while tube line stages were musical, yet both camps were low distortion
Great story 🙂 Reminds me of my dad who stored a Sony tube tape deck for years as it had a problem in the left channel. Every now and then he took it out of storage and tried to repair it but he did not succeed. Tubes, resistors, caps all parts had been replaced a few times already....
Then, after many years, it turned out to be that he had been repairing the right channel quite consequently for a quite long time 😀
Good to have clarified the point, thank you. I was already beginning to believe that "I have a Tuscan in my ear", as we say here. 😀
Hi Flaxxer and friends here, I suggest reading two simple articles, written by the notable John Lenard Burnet, on the links below. The world is driven by interests and the best ideas are not always adopted.
Amplifiers: Solid State amps verses Valve amps
Valve Amps: Valve verses Solid-state amps
Amplifiers: Solid State amps verses Valve amps
Valve Amps: Valve verses Solid-state amps
I have to admit that it always gives me a weird feeling - a mixture of wonder and uncertainty - when talking about "current amplification" vs. "voltage amplification"? I have read (very quickly) this article,
Amplifiers: Solid State amps verses Valve amps
and I wonder if we can make a TR work with + B 300 Volts on the manifold or a valve with + B 35 Volts on the plate ...
It is basic, in any circuit, for a current to flow there must be a voltage X and a conductive element between the (+) and the (-) that unites that difference in potentials.
It is the same as when lightning strikes, the potential of the earth is joined with that of the clouds by a conductor which in this case is the atmosphere loaded with moisture - water - which, as we know, is conductive.
So, be it a resistor, a TR or a valve, each of these different devices behaves according to its physical structure and a behavior that has been well studied and then put into practice to amplify small signals.
In TR we need little voltage and due to the phenomenon of doping, gaps, etc., etc.
(It is not the case here to detail this) will create currents that will circulate between the (E) emitter and the collector (C), controlled by the base (B). Which then will be voltages in the speaker and will circulate currents through it!
And in the valve to make current circulate, we must polarize the plate (A) with high voltages so that they can attract the electrons of the cathode (C), also creating a current, controlled by the grid (G) that will then be a voltage in the speaker through the output transformer, which will also then circulate a current when coupled to the speaker! ....
So all devices work with voltage and with currents, and the often used phrase "is a current amplifier" or "is a voltage amplifier" doesn't make much sense to me. Many people repeat this with the air of know-it-all, and lack the basic fundamentals of electronics to understand what they are saying. They should study and do some basic exercises on Ohm's Law.
So, for me, they will still be a tube amp or a transistor amp. The rest I leave to the developers....
Amplifiers: Solid State amps verses Valve amps
and I wonder if we can make a TR work with + B 300 Volts on the manifold or a valve with + B 35 Volts on the plate ...
It is basic, in any circuit, for a current to flow there must be a voltage X and a conductive element between the (+) and the (-) that unites that difference in potentials.
It is the same as when lightning strikes, the potential of the earth is joined with that of the clouds by a conductor which in this case is the atmosphere loaded with moisture - water - which, as we know, is conductive.
So, be it a resistor, a TR or a valve, each of these different devices behaves according to its physical structure and a behavior that has been well studied and then put into practice to amplify small signals.
In TR we need little voltage and due to the phenomenon of doping, gaps, etc., etc.
(It is not the case here to detail this) will create currents that will circulate between the (E) emitter and the collector (C), controlled by the base (B). Which then will be voltages in the speaker and will circulate currents through it!
And in the valve to make current circulate, we must polarize the plate (A) with high voltages so that they can attract the electrons of the cathode (C), also creating a current, controlled by the grid (G) that will then be a voltage in the speaker through the output transformer, which will also then circulate a current when coupled to the speaker! ....
So all devices work with voltage and with currents, and the often used phrase "is a current amplifier" or "is a voltage amplifier" doesn't make much sense to me. Many people repeat this with the air of know-it-all, and lack the basic fundamentals of electronics to understand what they are saying. They should study and do some basic exercises on Ohm's Law.
So, for me, they will still be a tube amp or a transistor amp. The rest I leave to the developers....
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I have no way to measure TIM (transient intermodulation distortion). There are far better experts for that.
yes of course
Transient Intermodulation Distortion
Modern amplifier distortion is controlled by negative feedback, which reduces the distortion in proportion to the feedback. Amplification is cheaply available so the apparent non-linearity can be reduced to arbitrarily low levels by sufficient feedback.
But the feedback signal takes time to get through the amplifier and back to the input negatively to quash the distortion. So when sudden changes (transients) occur there is a period during which the naked amplifier is exposed to the world, and the non-linearity adds intermodulation rogue signals to the original, which are not entirely canceled by the feedback. This is transient intermodulation distortion. What you need is an amplifier sensibly without distortion before applying feedback.
Transient Intermodulation Distortion
Modern amplifier distortion is controlled by negative feedback, which reduces the distortion in proportion to the feedback. Amplification is cheaply available so the apparent non-linearity can be reduced to arbitrarily low levels by sufficient feedback.
But the feedback signal takes time to get through the amplifier and back to the input negatively to quash the distortion. So when sudden changes (transients) occur there is a period during which the naked amplifier is exposed to the world, and the non-linearity adds intermodulation rogue signals to the original, which are not entirely canceled by the feedback. This is transient intermodulation distortion. What you need is an amplifier sensibly without distortion before applying feedback.
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"What you need is an amplifier sensibly without distortion before applying feedback."
I think this is a great idea 🙂
I think this is a great idea 🙂
The Pass Aleph-J is the closest I have heard a SS MosFet amplifier come to valve sounding. It's easy to build with PCBs available from the DIY-Audio store.
It's still not as pleasant as my EL34 PP amp.
It's still not as pleasant as my EL34 PP amp.
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As I understand it, intermodulation distortion is proportional to total harmonic distortion.
Negative feedback generally reduces THD.
Therefore, NFB generally also reduces IM.
However, if a lot of NFB is applied and it makes the output signal ring or otherwise be distorted because of instability (transient oscillations) then the circuit has not been compensated to work well with that high a level of NFB, which can introduce a different kind of distortion.
But that is not the same as saying TIM is caused by insufficient NFB.
Yup, that's the right idea.
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Negative feedback generally reduces THD.
Therefore, NFB generally also reduces IM.
However, if a lot of NFB is applied and it makes the output signal ring or otherwise be distorted because of instability (transient oscillations) then the circuit has not been compensated to work well with that high a level of NFB, which can introduce a different kind of distortion.
But that is not the same as saying TIM is caused by insufficient NFB.
Yup, that's the right idea.
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