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Bricks List: 36V & 48V Power Supplies (for Fosi, Aiyima etc.)

Also, I suspect that some posts here about the safety of these power bricks are made simply to undermine these Class D amps coming from China. Add a little fear to the conversations where possible to sow doubt about these products.
That's a very conspiratorial view of the world in a forum that dissects these devices and delves into the minutiae of the components used and their performance. A power supply is a component of the solution. Certified products are designed better and use higher quality components in order to pass certification tests. Having designed and built systems to comply with safety standards I know that they force higher quality components and manufacturing processes. An uncertified device is an unknown quantity.

Many thousands of homes in the US are old enough so that their entire electrical systems are out of date and out of code. There are plenty living in the US who still have knob and wire systems in the walls. There are millions of devices with old cords, cracked sockets, loose internal connections, etc. etc.. There are millions of internal wires running in houses that have been nicked, soaked, chewed on by squirrels, etc. Small Li-Ion units are plugged in by the literal millions. The failure rates are infinitesimally small for all of these gadgets.
These all represent risks. The overall goal of safety standards is to reduce risks, especially unnecessary risks that we know how to minimize. These standards and electrical codes are the reason why all those perils that you describe have not done more damage. The systems are designed to be resilient in the face of multiple failures. I find it odd to point to the overall robustness of a system that has been regulated for many decades and suggest that the standards have little to do with it. We would hope that these electrical systems were within code when installed. Just because we know better now, doesn't mean we knew nothing then and it doesn't mean we won't know even better in the future. We should be promoting safety regulations not undermining them.

Failure rates are small because of standards and vigilance in removing unsafe devices from the market.

By the way, according to the US Fire Administration, "The 2022 national estimates for residential building electrical malfunction fires and losses show that there were: 26,100 fires. 185 deaths. 850 injuries"
 
That's a very conspiratorial view of the world in a forum that dissects these devices and delves into the minutiae of the components used and their performance. A power supply is a component of the solution. Certified products are designed better and use higher quality components in order to pass certification tests. Having designed and built systems to comply with safety standards I know that they force higher quality components and manufacturing processes. An uncertified device is an unknown quantity.


These all represent risks. The overall goal of safety standards is to reduce risks, especially unnecessary risks that we know how to minimize. These standards and electrical codes are the reason why all those perils that you describe have not done more damage. The systems are designed to be resilient in the face of multiple failures. I find it odd to point to the overall robustness of a system that has been regulated for many decades and suggest that the standards have little to do with it. We would hope that these electrical systems were within code when installed. Just because we know better now, doesn't mean we knew nothing then and it doesn't mean we won't know even better in the future. We should be promoting safety regulations not undermining them.

Failure rates are small because of standards and vigilance in removing unsafe devices from the market.

By the way, according to the US Fire Administration, "The 2022 national estimates for residential building electrical malfunction fires and losses show that there were: 26,100 fires. 185 deaths. 850 injuries"

1) No it's not and you might know that if you had been here for more than one day.
2) Now, tell us how many of those injuries/deaths were caused by fires caused by small power bricks manufactured in the last year.
 
1) No it's not and you might know that if you had been here for more than one day.
2) Now, tell us how many of those injuries/deaths were caused by fires caused by small power bricks manufactured in the last year.

I don't think that anyone gathers stats on things like when was the power supply that caused the fire manufactured.
However, they do gather stats close to what you are asking about. This is from the National Fire Protection Association.
The report is here https://www.nfpa.org/education-and-...rch/fire-statistical-reports/electrical-fires

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That's operation in obvious bad faith on the part of that insurer. Consumers would love to know which insurer your friend works for so that they can avoid this bad faith business. Insurance is always a balancing act but insurers in the US are pushing hard on the "screw you" aspect of their business models in recent years and I predict the worst offenders will go defunct as consumers reject them and competitors provide better terms and good faith service.

Also, I suspect that some posts here about the safety of these power bricks are made simply to undermine these Class D amps coming from China. Add a little fear to the conversations where possible to sow doubt about these products.

Many thousands of homes in the US are old enough so that their entire electrical systems are out of date and out of code. There are plenty living in the US who still have knob and wire systems in the walls. There are millions of devices with old cords, cracked sockets, loose internal connections, etc. etc.. There are millions of internal wires running in houses that have been nicked, soaked, chewed on by squirrels, etc. Small Li-Ion units are plugged in by the literal millions. The failure rates are infinitesimally small for all of these gadgets.

One thing I know is that I'm much more comfortable living with Chinese power bricks than some of the old Class A and Class AB amps I've had in the house.
This is really ridiculous. Do you think that the big American and European manufacturers have brought users into the forum and this thread who are raising doubts about cheap and uncertified power supplies for Class D amplifiers? Honestly :facepalm:
Take a look at the users who are expressing doubts here and you will notice that they are users with experience and often also a professional background.

I myself work in industry and deal with switching power supplies in all performance classes. Durability, reliability and quality definitely have something to do with certifications and tests, but also with the manufacturer.
While brand manufacturers often far exceed the specifications and pass all stress tests without any problems, I have seen many cheap switching power supplies, with and without certification, literally burn up on the test bench.

Of course, the power supplies in the amplifiers are not subjected to such a high load and often only for a few hours a day or week. And yes, there can be really good power supplies and it seems that some Class D amplifier manufacturers are paying more attention to quality. But without the appropriate tests and test results, this is of no use to the end user.
You must also not forget that switching power supplies are mass-produced goods and the manufacturer makes $10,000 more profit on just one model with savings of a few cents on components. With a dollar saved, that can easily add up to $50,000 - $100,000 more profit.

Personally, I don't care; as I've already written, no power supply or device is connected to the power grid when I leave the house or go to sleep.
If I can avoid it, I don't order power supplies with the amplifiers. I usually use industrial power supplies that have been discarded after 5-7 years.
It is also interesting that high-quality switching power supplies in 24/7 operation can easily last 5-10 years, often longer, while the cheaper ones often fail much sooner. And at my last employer, I had experience with several thousand of these bricks in daily use.
 
This is really ridiculous. Do you think that the big American and European manufacturers have brought users into the forum and this thread who are raising doubts about cheap and uncertified power supplies for Class D amplifiers? Honestly :facepalm:
Take a look at the users who are expressing doubts here and you will notice that they are users with experience and often also a professional background.

I myself work in industry and deal with switching power supplies in all performance classes. Durability, reliability and quality definitely have something to do with certifications and tests, but also with the manufacturer.
While brand manufacturers often far exceed the specifications and pass all stress tests without any problems, I have seen many cheap switching power supplies, with and without certification, literally burn up on the test bench.

Of course, the power supplies in the amplifiers are not subjected to such a high load and often only for a few hours a day or week. And yes, there can be really good power supplies and it seems that some Class D amplifier manufacturers are paying more attention to quality. But without the appropriate tests and test results, this is of no use to the end user.
You must also not forget that switching power supplies are mass-produced goods and the manufacturer makes $10,000 more profit on just one model with savings of a few cents on components. With a dollar saved, that can easily add up to $50,000 - $100,000 more profit.

Personally, I don't care; as I've already written, no power supply or device is connected to the power grid when I leave the house or go to sleep.
If I can avoid it, I don't order power supplies with the amplifiers. I usually use industrial power supplies that have been discarded after 5-7 years.
It is also interesting that high-quality switching power supplies in 24/7 operation can easily last 5-10 years, often longer, while the cheaper ones often fail much sooner. And at my last employer, I had experience with several thousand of these bricks in daily use.

Does this include every appliance? Every electrical device? Your HVAC? Your dishwasher? Seems paranoid TBH. If you're that afraid, do you drive a car on the roads?

I'll say again that, like clockwork, every time a thread gets going that involves discussion of Class D amps, including in this case a discussion of power bricks for same, several posters arrive to trash them.
 
Does this include every appliance? Every electrical device? Your HVAC? Your dishwasher? Seems paranoid TBH. If you're that afraid, do you drive a car on the roads?

I'll say again that, like clockwork, every time a thread gets going that involves discussion of Class D amps, including in this case a discussion of power bricks for same, several posters arrive to trash them.
That's complete nonsense, of course. I always have 2-phase sockets and power strips and have already been checked three times by energy companies because my power consumption was far too low. In addition to electricity, it also reduces all emissions.
In this millennium alone, I have saved well over €20,000 and my devices also last longer than average. On average, a household of this size uses three times as much electricity and I don't do without anything. I really must be an idiot.

I haven't had a car for a few years now and only drive when I absolutely have to. After driving over 1,300,000 kilometers, I just didn't feel like it anymore. When I need to, I use a Cupra VZ5, it's amazing what you can get off the shelf these days.

And these posters are absolutely right when it comes to uncertified and unapproved power supplies for which no one takes responsibility in the event of damage. Even worse when ignorant consumers are deceived by fake labeling, because that's exactly what it's about: making unsuspecting users aware of the problem.
Or do you think that a few deaths a year are OK if the manufacturers save money and the power supplies are cheaper?
Because according to the report posted by @Unbalanced , at least 47 people die each year in fires caused by power supplies and transformers. And that's not the worldwide number.

Maybe a cheap capacitor bursts in one of these power supplies, then you can think about it for several weeks until your apartment no longer smells.
 
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That's complete nonsense, of course. I always have 2-phase sockets and power strips and have already been checked three times by energy companies because my power consumption was far too low. In addition to electricity, it also reduces all emissions.
In this millennium alone, I have saved well over €20,000 and my devices also last longer than average. On average, a household of this size uses three times as much electricity and I don't do without anything. I really must be an idiot.

I haven't had a car for a few years now and only drive when I absolutely have to. After driving over 1,300,000 kilometers, I just didn't feel like it anymore. When I need to, I use a Cupra VZ5, it's amazing what you can get off the shelf these days.

And these posters are absolutely right when it comes to uncertified and unapproved power supplies for which no one takes responsibility in the event of damage. Even worse when ignorant consumers are deceived by fake labeling, because that's exactly what it's about: making unsuspecting users aware of the problem.
Or do you think that a few deaths a year are OK if the manufacturers save money and the power supplies are cheaper?
Because according to the report posted by @Unbalanced , at least 47 people die each year in fires caused by power supplies and transformers. And that's not the worldwide number.

Maybe a cheap capacitor bursts in one of these power supplies, then you can think about it for several weeks until your apartment no longer smells.

Uh huh. Sorry but you sound more than a little off here. Best of luck and I'll continue to live my life without odd paranoia about the power brick supplying my Fosi amp. Hopefully it won't kill me and I'm pretty sure it won't.
 
Hello there, is there already any insight on the new AIYIMA DC48V 10A GaN supply?

Herr are 2 links to it:
Hi I'm really not liking a fan hole in that PSU the only time I've seen that are low level apple PC's where the Power supply unit needed to be flat and low, but there's no exit hole?
Is there even a small fan in there?
What happens when it's collected dust and fur?
 

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I'll say again that, like clockwork, every time a thread gets going that involves discussion of Class D amps, including in this case a discussion of power bricks for same, several posters arrive to trash them.

There are varying opinions on everything under the sun. This topic being no exception.

Now particularly on the topic of power bricks I would like to translate. When people use things that are potentially dangerous, other people show up to inform them of the risks. I am puzzled why that is viewed in some sort of negative light as an attempt to trash the units. Many people wrote about getting alternate power supplies because they like the units so much and because the units perform better with better power. I wrote about how the supply that Fosi sourced had obtained an important safety certification (a good thing as there seems to be some confusion about that).

Manufacturers make choices when they assemble components into a solution that they bring to market. I feel that the manufacturers that choose higher quality components should be recognized for that because it usually means that their products cost a little more. Conversely manufacturers that assemble lower cost solutions should be scrutinized to understand what allows them to do so. Have they developed a more efficient manufacturing process or circuit design, or have they cut corners on quality? It's truly fantastic when it's one of the former as that tends to move the industry and the state of the art forward. It's sad when the latter as it amounts to taking advantage of consumers that don't know any better as @Roland68 has also mentioned.

You can choose to take whatever risks you want. Yes, the likelihood of any individual failure is very small. Does that mean we should stop paying attention to the risks or be uninformed about them? How would this apply to the aviation industry where the consequences of these risks are more severe? Yeah, Boeing put out a defective product, but the chances of getting killed in a plane crash are infinitesimally small. Don't worry. Be Happy.
 
There are varying opinions on everything under the sun. This topic being no exception.

Now particularly on the topic of power bricks I would like to translate. When people use things that are potentially dangerous, other people show up to inform them of the risks. I am puzzled why that is viewed in some sort of negative light as an attempt to trash the units. Many people wrote about getting alternate power supplies because they like the units so much and because the units perform better with better power. I wrote about how the supply that Fosi sourced had obtained an important safety certification (a good thing as there seems to be some confusion about that).

Manufacturers make choices when they assemble components into a solution that they bring to market. I feel that the manufacturers that choose higher quality components should be recognized for that because it usually means that their products cost a little more. Conversely manufacturers that assemble lower cost solutions should be scrutinized to understand what allows them to do so. Have they developed a more efficient manufacturing process or circuit design, or have they cut corners on quality? It's truly fantastic when it's one of the former as that tends to move the industry and the state of the art forward. It's sad when the latter as it amounts to taking advantage of consumers that don't know any better as @Roland68 has also mentioned.

You can choose to take whatever risks you want. Yes, the likelihood of any individual failure is very small. Does that mean we should stop paying attention to the risks or be uninformed about them? How would this apply to the aviation industry where the consequences of these risks are more severe? Yeah, Boeing put out a defective product, but the chances of getting killed in a plane crash are infinitesimally small. Don't worry. Be Happy.
In addition, everyone should think about the following in relation to these power supplies.
The thing that bothers me most about such power supplies is that there are no technical data and data sheets available for most power supplies.
Everyone should ask themselves why a reputable manufacturer is not able to make technical data and data sheets for its power supplies available for download on its website.
The answer is simple, then it is not a reputable manufacturer.
These data sheets from reputable manufacturers say a lot about a power supply, especially about areas of application, performance under various criteria, service life, short-term additional power, efficiency, etc., the list is long.
Of course, a dubious manufacturer would not want to give out such information because the information would then be comparable and verifiable.

As an example, I will take a tried and tested Mean Well Brick power supply with 48 volts and 4.6A, the GSM220B48-R7B.
In addition to all the necessary documents and data sheets, this power supply also has approval for the medical sector, including breath machines. Anyone who knows anything about it knows how complex and expensive this approval is.
The power supply is sold to end customers in Germany and the EU for around €75 including taxes. How much does a power supply like this from one of the Class D amplifier manufacturers cost?

The GSM220B48-R7B also has a 3-year manufacturer's guarantee that you can absolutely rely on.
- Short-term increase in performance of over 30%
- Average service life of over 8 years with continuous 24/7 operation
- Efficiency 94.5%
- Ripple noise 150mVp-p
Just a few key data, you can find the complete data sheet here GSM220B48-R7B
Please note that you need an adapter or a different plug for a Class D amplifier. Information about this can be found in the data sheet, or available adapters.
 
A powersupply that alone costs more than a Fosi v3 with PSU. So what?
Can you please post a link to the V3 for a cheaper price with a power supply of this power class? Thanks in advance.

I was referring to the 48v/5A Fosi power supply for around $72 and the V3 with the 48v/5A power supply for around $126 on the Fosi Audio site.
The V3 is available on offer for around €50, so you get a similar price with the Meanwell power supply.
This is just to show interested users that there are high-quality and affordable alternatives. In practice, the Meanwell should last at least 10-20 years (over 70,000 hours).
You can get a 48v/5A power supply without real documents and without technical data for as little as €/$20-25, but you are responsible for that yourself.

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Can you please post a link to the V3 for a cheaper price with a power supply of this power class? Thanks in advance.
At release you could get a v3 with 32 V PSU for $79.99 from Fosi and there were sometimes better deals than that on Ali. It appears the price went up and that is no longer the case.
 
At release you could get a v3 with 32 V PSU for $79.99 from Fosi and there were sometimes better deals than that on Ali. It appears the price went up and that is no longer the case.
You can get these simple 32v 5A bricks for 15-21 $/€, so it wasn't even a special offer.

I bought the same 32v 5A power supply in Germany from an eBay dealer with a TPA3255 amplifier (case and BT) including shipping for €43.
This shows how cheap these power supplies really are.

Bildschirmfoto 2024-08-29 um 12.29.06.png
 
You can get these simple 32v 5A bricks for 15-21 $/€, so it wasn't even a special offer.

I bought the same 32v 5A power supply in Germany from an eBay dealer with a TPA3255 amplifier (case and BT) including shipping for €43.
This shows how cheap these power supplies really are.

View attachment 389183

I did a little searching and found the wholesale listing from the OEM for a similar power supply with less power.
Power Supply OEM
The wholesale price is USD $2.30. Even being generous I would expect a 48V supply would still be less than USD $3.00.
I thought I knew something, but I was surprised.
 
I did a little searching and found the wholesale listing from the OEM for a similar power supply with less power.
Power Supply OEM
The wholesale price is USD $2.30. Even being generous I would expect a 48V supply would still be less than USD $3.00.
I thought I knew something, but I was surprised.
And that is what most people do not understand or do not know.
Regardless of certificates, declarations and data sheets, it is impossible that high-quality parts/components are installed at such a price.
For less than $3 (or $2.30) you need a power supply housing, the power connector, the DC cable, DC plug and a circuit board. And at this point there is not a single component, no one has yet assembled or tested the power supply, and the manufacturer and the seller still have to make money from it.
It should be clear to everyone that with the number of units, every cent or $ saved means a significant additional profit. And if the manufacturer and seller are not liable and there are no tests, who should care?

Another problem is that completely different qualities of power supplies are installed in the same or similar housings. You cannot see that from the outside.
Yet another problem is third-party sellers who simply supply a cheaper power supply that is difficult to distinguish.
For example, when I ordered well-known Class D amplifiers on Aliexpress, I received two devices that had a simpler circuit board and all the advertised high-quality components were missing and were replaced with parts that were 20 times cheaper.

And that doesn't mean that Fosi and other well-known amplifier manufacturers don't supply good power supplies, perhaps the newer generations are even very good.
But without the proven tests, declarations, certificates and data sheets, you can't know that reliably.
 
Is the 36v Aiyima PSU still a decent upgrade over the 32v with the Fosi V3?

Based on Amir's tests the 36v 6a fell short of it's claimed ability, delivering only 6 watts per channel more into 8 ohms than the 32v 5a.
 
Is the 36v Aiyima PSU still a decent upgrade over the 32v with the Fosi V3?

Based on Amir's tests the 36v 6a fell short of it's claimed ability, delivering only 6 watts per channel more into 8 ohms than the 32v 5a.
I recently discovered an offer on Amazon.de for a variable switching power supply with 0-48V / 0-12.5A (600 Watt), which is certainly interesting for users who want to try out different amplifiers with different voltages and for DIYers. Also available with 0-60V / 0-10A.
It is particularly interesting for tests to limit the output current in order to minimize possible damage.
Unfortunately, I can't say anything about the quality, but since these power supplies are also used for CNC machines and 3D printers and there isn't much in the comments about failures, they seem to deliver high performance.
BOSYTRO Adjustable Switching Power Supply 0-48V 0-12.5A 600W

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Has anyone tried the AIYIMA 350W @ 48V aluminum case PSU, priced around $70-$90? (https://www.aliexpress.com/item/1005001493689010.html)?
1728775472140.png

After doing a lot of research on AliExpress, I found out that the assembled PSU PCB inside seems to be quite inexpensive—about $25 including shipping. Here's the PCB:
Left image from: https://www.aliexpress.com/item/1005006800930543.html
Right Image from: https://www.aliexpress.com/item/1005005864004846.html
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Because of this, I'm considering building the PSU myself. You can get the same aluminum case for around $20 here:
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However, I'm a bit concerned about the quality of the PCB. Does anyone know more about these 350W supplies?
Another option is to get the A07 Pro, bundled with a 48V, 5A brick PSU for an additional $25. (https://www.aliexpress.com/item/1005005041367134.html)
I'd love to hear your thoughts or any feedback
 

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