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Power amplifier tests with respect to FTC: 16 CFR Part 432 (July 5, 2024) requirements on output power claims

The main market for Chinese companies is China.
Polling on this forum suggests that there are, would be, more "foreign" users than Americans… :)
First, let’s not deceive ourselves into believing that the users here are representative of most consumers. :)

Second, given the numerous U.S.-based YouTubers who endorse products like Chinese amplifiers, I would bet that the U.S. is, if not the largest, then at least the second-largest market for many of these manufacturers. An import ban would undoubtedly have a significant effect on their finances.
Furthermore, the fines should not be underestimated either.
 
I think (hope) we can all agree, amplifiers have improved in many areas and regressed in many others.

I am the first to admit the leaps and bounds with Class D performance are incredible. Two to three orders of magnitude better than the breakthrough Sony Class D (TAN-88B) from 1977. But that is 47 years on... And, those Sonys were not ultimately reliable. Most are in landfill (sadly).

But they happily delivered their rated power (and considerably more on the ones I tested) according to the 1974 amplifier rule FTC standards at the time. (160wpc, 20-20k, <0.05%- IMD <0.01%) No help needed. No excuses.

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Why do you think that was the case (pun intended)? You are looking at a die-cast, machined solid block of aluminium as a chassis. You are looking at a pile of VFETs and a purpose built SMPS to run the whole show. The failure mode (after >20 years) was SBG (Sony bond glue) and HV capacitors, not heat. They lasted for at least 2 decades.

I have Hypex NC-252MPs sent to me that failed in a few short years. Look at my posts here on ASR and details. They are garbage products and not fit for purpose.
 
First, let’s not deceive ourselves into believing that the users here are representative of most consumers. :)

Second, given the numerous U.S.-based YouTubers who endorse products like Chinese amplifiers, I would bet that the U.S. is, if not the largest, then at least the second-largest market for many of these manufacturers. An import ban would undoubtedly have a significant effect on their finances.
Furthermore, the fines should not be underestimated either.
What US and EU is for the Chinese companies is mostly about fame and marketing.
Hard-core audiophiles there are even worst than the West,have a look at their gear.

If a product is well regarded here is good for there as well.
It's not the numbers.it's the potential.
 
It's important to understand how trade operates. They cannot simply drag anyone to court, if that's your assumption. Instead, they can encourage compliance with regulations through warnings and fines, and if a company still does not comply, they can enforce an import ban
That's pretty much the only alternative is a ban on non compliant amplifiers to
Title 16 - Chapter 1- Subchapter-D Part 432 if they don't have a United States distributor or sales network. I'm sure this will be high on the FTC list of priorities, enforcement of a regulation that was to be sunset then brought back to life. IMO the real world scenario the FTC is glad the rigamore is over and doesn't look over their shoulder barring a class action lawsuit.
 
Many companies produce and sell, only for the Chinese market. :)
 
Many companies produce and sell, only for the Chinese market. :)
The most outrageous room/system in Munich this year was Chinese,an ESD Dragon something,with a cost of couple of million euro (without taxes,etc)
Don't think it's made for western market .
 
They absolutely help the consumer. Tell those consumers who are using 40-50 year old amplifiers still operating perfectly because they were built properly in the first place.

Contrast that with the few year old disposable amplifiers people make reliability threads about...

This is anecdotal evidence and might get traction elsewhere but not here. If you search more broadly, you would find plenty of complaints about Class AB failures too. Amir and others have posted bad experiences with Class AB products as well. Not too surprising that each individual values their own experience though…

We challenge others that post on ASR with anecdotal evidence. If we accept anecdotal evidence of one person over another, we are no better than a more subjectivist forum. When we have more than just anecdotes as evidence, we get back to science.
 
They absolutely help the consumer. Tell those consumers who are using 40-50 year old amplifiers still operating perfectly because they were built properly in the first place.
How much electricity do they consume?
 
But they happily delivered their rated power (and considerably more on the ones I tested) according to the 1974 amplifier rule FTC standards at the time. (160wpc, 20-20k, <0.05%- IMD <0.01%) No help needed. No excuses.
Hmh. These were 2700 DM in Germany then, four of these would buy you a Volkswagen (Golf/Rabbit). And despite the cost and the material battle these were not "ultimately reliable". And how do you know there were no broken units already in 1980? Maybe it was just because not so many were sold at all?
So what is this specification of "continuous power" in the end good for?
Obviously not for reliability and certainly not for music, as this is a totally different kind of signal. I do see the vendors and sellers of heat sinks who will enjoy the regulation though.
 
How much electricity do they consume?
Idle power consumption of the Hypex NC252MP module (amp + SMPS) is 17W, measured. This may be more or less than in case of class AB amplifier, depending on its designed idle current. The advantage of class D lower power consumption occurs only at higher power. In case of middle volume listening room conditions, there is no advantage of class D power consumption.
 
Hmh. These were 2700 DM in Germany then, four of these would buy you a Volkswagen (Golf/Rabbit). And despite the cost and the material battle these were not "ultimately reliable". And how do you know there were no broken units already in 1980? Maybe it was just because not so many were sold at all?
So what is this specification of "continuous power" in the end good for?
Obviously not for reliability and certainly not for music, as this is a totally different kind of signal. I do see the vendors and sellers of heat sinks who will enjoy the regulation though.
You made me enter ali but it's ok :p

If this 14Kg knock-off AR case is sold for 90 euro or something to consumers I expect it to be around 40-50 euro for companies.


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add some for postage,etc,subtract the cost of the previous smaller one and is still not THAT much.
 
Who the f... soldered this???

View attachment 413338

Almost definitely (originally) a machine but is likely a human rework. I worked for an electronics manufacturer and despite high standards, stuff happens. It may have been bad flux, a machine malfunctioning, poor cleaning or something else, but we still had recalls for excess flux, solder fingers or the occasional bad tester. We are accustomed to high quality electronics but is not perfection. Sometimes we would catch a quality issue before they shipped but not always (despite a cultural of high quality).

As for internet reviewers posting bad experiences, combine the above and add my early post on anecdotes. If Fosi has a major quality problem and shipped them to customers, then need more than 1 reviewer's amp failure in an informal "test" to indicate.
 
Almost definitely (originally) a machine but is likely a human rework. I worked for an electronics manufacturer and despite high standards, stuff happens. It may have been bad flux, a machine malfunctioning, poor cleaning or something else, but we still had recalls for excess flux, solder fingers or the occasional bad tester. We are accustomed to high quality electronics but is not perfection. Sometimes we would catch a quality issue before they shipped but not always (despite a cultural of high quality).

As for internet reviewers posting bad experiences, combine the above and add my early post on anecdotes. If Fosi has a major quality problem and shipped them to customers, then need more than 1 reviewer's amp failure in an informal "test" to indicate.
I get all that and I agree.
But that's not a rework.Anyone who has soldered something more than twice in it's life would do it better.I give another point for it being SMD but that's it.
That's a horror pic,amp or otherwise.

Edit:for those who didn't pay attention to the pic,it's not only the bad soldering,it's that the caps who supposed to be in parallel now they are at series too (all combined :facepalm: )
No wonder it failed even been at idle.
 
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As for internet reviewers posting bad experiences

For the most it's actually a reviewer who's very happy with these amps. But he gives the advice to use these amps with forced cooling. Thermal managament is an important part of this discussion.
 
For the most it's actually a reviewer who's very happy with these amps. But he gives the advice to use these amps with forced cooling. Thermal management is an important part of this discussion.

Fair enough, but the post here was about 1 of 6 failing...

Despite suggested thermal management, if the product has a design or manufacturing defect, then its thermal management may be compromised regardless. If it is well designed and built, it should only need added cooling under limited conditions.
 
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