Can you expand on your theory that a single '150A' transistor would be enough to create a low distortion amp.
What design do you have in mind.
You seem to know a LOT about circuit design.
It makes me wonder why such an amp does not exist yet. Perhaps you could design such an amp and simulate it in Spice showing great performance.
Afterall ... in spice you could just 'design' devices that have those properties.
Let me know when you have come up with the revolutionary design that will increase performance of AB amps.
I made this thread asking if the reason distortion (THD+n) increases at 12 watts with 15A transistors (at the 8-10% max spec'd current) on amplifiers that have effectively unlimited power supplies is that the transistors start operating in their nonlinear range at that point (12w)
Nobody answered me - my original postulation remains the only theory. As far as I can tell there is no other plausible reason.
I made this thread asking if the reason distortion (THD+n) increases at 12 watts with 15A transistors (at the 8-10% max spec'd current on amplifiers that have effectively unlimited power supplies) is that the transistors start operating in their nonlinear range at that point (12w)
It is not the current rating or amount of OP devices but the design around those components.
The component choice, overall circuit, gain, PCB layout, (overall and/or local) feedback and the load determines this point.
Part of it is the OP devices (be them FET, MOSFET, or transistors.
When you have spice or Multisim you can tinker with component properties and circuits and see how that works out.
To include PCB layout issues is another thing entirely and can also be simulated.
It simply is reaching its maximum S/THD-N ratio at those levels. It is determined by the design.
There is no 'tuning' of an amp to 12W. No conspiracy, no deliberate 'holding back' of performance, no deliberate choice of 'inferior' OP devices, just sufficient engineering for the intended purpose which is not SOTA but good enough for the money.
I already answered all of this in post #2 but you did not seem to get the gist of what I wrote.
But they're all 12 watts. And the only commonality is the 15A rating of the transistor.
And the group who tuned each circuit.
But the thing is... why would they tune the 105W amp to 12W and the 150W amp to 12W
Like the Denon rate about 100watt for 9 Channel. That 900watt combine power max. But your Denon will just consume 600-700 watt from power supply. How can you output be higher than input. And I have not talking about power doubling at lower ohm speaker.
So much nonsense packed into a single post. I do congratulate you for the efficiency.So harmonic distortion is rising above the noise floor and continuing to gain ground until clipping.
It always seems to rise... what's the cause?
Why isn't it controlled for?
It's terrible! If you can see it, you can hear it. How does it sound? Like a lack of detail and listening fatigue. How does a lack of detail sound? Like rolled off highs
"But frequency response is flat"
Maybe it is, but that's not how hearing works.
So we know why it should be gone
So why aren't designers fixing their faulty designs?
I can't help but think that a transistor with a more linear output would at least reduce second harmonic distortion (asymmetical)
Edit: and third harmonic distortion from rounded peaks "higher supply voltage, higher current transistor"
-more heat, lower performance
balancing act.
But so many of these designs are so bad they're unlistenable. Turn them to move a 6 inch woofer 1/16th inch and you can't hear the person beside you.
6 inch woofer playing same song moving 1/4 inch? Easy to hear them
The reason someone who says they can hear the difference between amplifiers can't A/B them on the spot double blind is they don't get time to get familiar and with their own music. The distortion profile of one can be so different from another that you can tell which amp is playing just by how one synth sounds. Double blind that person after practice with that song they know, and they'll pick right 100% of the time.
Harmonic distortion is why this hobby isn't 10x bigger.
There are people with $10K amps and speakers who still haven't heard high fidelity music
So harmonic distortion is rising above the noise floor and continuing to gain ground until clipping.
It always seems to rise... what's the cause?
Why isn't it controlled for?
It's terrible! If you can see it, you can hear it.
How distortion sounds depends on the level of distortion, harmonic spread, the recording (masking).How does it sound? Like a lack of detail and listening fatigue.
Maybe it is, but that's not how hearing works.
We know when it isn't relevant. It does not have to be gone or below measurable levels.So we know why it should be gone
Because they don't need to above a certain point when the design goals are met.So why aren't designers fixing their faulty designs?
That is correct.I can't help but think that a transistor with a more linear output would at least reduce second harmonic distortion (asymmetical)
That's not my opinion. Unlistenable speakers and headphones.... sure. Problematic rooms... sure. Electronics... never unless they are broken or really poor in design.But so many of these designs are so bad they're unlistenable.
Depends on your definition of high-fidelity.There are people with $10K amps and speakers who still haven't heard high fidelity music