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The World's First Power Amplifier with SINAD over 120!!!

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The amp hasn't even been released yet and there is already argument brewing... I'll wait for test results and a teardown.

I do find the power vs THD+N with both channels driven using a 45kHz bandwidth and 6 different frequencies plotted (not just 1kHz) shown in testing here useful.

L7 must have recently altered this comment at the end of the AHB2 measurements;

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JSmith
 
You have answered your own question. JA works for Stereophile and his reviews are based on the magazine's editorial values. However, his measurements are there for all to see. It is for the reader to understand them. JA's measurements are objective, his comments are subjective.
What values? The only value is to make money
Look at the crap they recommend

And obviously if he is the golden standard to go guy the readers will also read what he writes and trust him to give them the right opinion. Most people are after all not very scientifically literate (heck, about 1/4 in USA do not even know where the sun goes at night).

(but, this is all off topic. Let's wait for the reveal instead)
 
and that is not a value? :D
The price of everything and the value of nothing... so to speak
A publication that recommends the above stuff in the link I posted can't really be written by people who like people.
It's frankly quite immoral.
 
Sorry, that's just rubbish. That harks back to the 1970s when THD numbers were the only number people bought their amplifiers based on. How did that work out? Hint: A whole lot of crap sounding amplifiers were bought by ignorant customers.

THD can go sky high at either end of the spectrum. You need to understand, 1kHz is the best case number, not the worst case. 20Hz-20kHz is the minimum bandwidth to specify THD. Nothing else has meaning. 1kHz numbers are for cheaters.

ASR doesn't test for single channel vs both channels. You have no idea how well regulated the supply is and how it affects the numbers.

You also have no idea what the actual, full power continuous ability of the amplifiers tested are, because that isn't tested. ASR's numbers are a non-specific, unspecified period of time, whereas the actual requirements are specific, advertised and required. The FTC requirements are clear and yet ASR does not test in accordance with those requirements.

250mW to rated power for THD over the 20Hz-20kHz bandwidth.
Full rated power for 5 minutes minimum.

Stereophile test accordingly, and that is why @John Atkinson (JA's) amplifier tests are the gold standard.

The duration comments are interesting.

I previously had two Behringer A800 amplifier, when I bench tested them I found I could achieve the same power that Amir did but only for about 10 seconds at which time a limiter kicked in and power output dropped. Maybe it was a design change from the amplifier that Amir reviewed but it has certainly made me a bit wary of ASR power sweeps.

Michael
 
It's a metric borne out of some research, paid for, sponsored and driven by a conglomerate only interested ultimately in profit. That a supposedly 'independent' website takes it on as utter "gospel" (in the absence of anything else they can hang their hat on) is unfortunate. Publicising smiley EQ curve 'preferred' responses as accurate is even worse. But it is, what it is. I shake my head.

Like all corporate research, you have to weigh up the science, the facts and the BS.

Harman Kardon once was an excellent company, especially when they outsourced their design, manufacture and production to a particular Japanese company that shall remain anonymous. Their gear was insanely good, but expensive. But that was the early 1980s.

Harman as a group, prior to the Samsung buyout, just sucked up everything they could, ruined it, and then rinsed and repeated.

JBL was wrecked by Harman in the 1980s. By 1990, they were a shell of speaker company. Now all they can do is release L100 'tributes' and attempts to regain some credibilty by painting a few cabinet baffles 'JBL pro blue' and sticking some horn loaded compression drivers in 2-way boxes, pretending they are SOTA. Yawn.
People here don’t worship the score. That’s total straw man. The highest answer was that it has some value but not definitive. Which is a perfectly reasonable answer, and a summary of your own position.
 
It's JA commenting on his measurements, certainly he should understand them very, very well?
Yes he does. He knows very well what he is doing, which cannot be said about many posters here.
 
However, his measurements are there for all to see. It is for the reader to understand them.
But apparently mine aren't? I post a ton of measurements but you and john focus on one number and complain that you did that?
 
Many here of course do, repeatedly asking question what is the 5W 1kHz SINAD.
It is a litmus test that is heck of a lot more valid than 1 watt numbers the rest of the world is using.
 
Yes he does. He knows very well what he is doing, which cannot be said about many posters here.
Some posters here seem to have a mission to just complain. Is it your position that consumers would be better served with no measurements as opposed to having mine?
 
I previously had two Behringer A800 amplifier, when I bench tested them I found I could achieve the same power that Amir did but only for about 10 seconds at which time a limiter kicked in and power output dropped. Maybe it was a design change from the amplifier that Amir reviewed but it has certainly made me a bit wary of ASR power sweeps
I did one continuous test and blew up an amplifier. Such a test doesn't represent music listening so I can't defend it either.
 
Yes but a continuos test tells something about the design competence and reliability. It separates toys from real amplifiers. JA is always doing a 30 min preconditioning at about half maximum power, now maybe at 1/8 power.
 
Understood. For my own curiosity, how long does that power sweep test take?
I am just estimating but I think it is one minute from start to finish. About 5 to 10 seconds are under heavy load. Timing is variable and depends on how stable thd+n readings are.
 
I am just estimating but I think it is one minute from start to finish. About 5 to 10 seconds are under heavy load. Timing is variable and depends on how stable thd+n readings are.
amirm, What amp did you use to test the speakers? AHB2?
 
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