Amp power supply problem

[ra-audio]

Hi all!

Aiyima A07 PRO amp. I bought one on Aliexpress (good price) about 10 days ago, and it arrived today.

Slight problem - no power unit with the amp, and the user manual warns that it should be used with "the switching power supply of the regular manufacturer".

This is the first time I've ever run into a situation like this - any ideas, suggestions for something that will work ok?

I've already left a message for the seller, but I'll be surprised if that leads anywhere.

Thanks

 

[TLS Guy]

Hi all!

Aiyima A07 PRO amp. I bought one on Aliexpress (good price) about 10 days ago, and it arrived today.

Slight problem - no power unit with the amp, and the user manual warns that it should be used with "the switching power supply of the regular manufacturer".

This is the first time I've ever run into a situation like this - any ideas, suggestions for something that will work ok?

I've already left a message for the seller, but I'll be surprised if that leads anywhere.

Thanks

I have researched this. The supplied power supply was inadequate and blows up.

Amir recommends this power supply.

I can see why the supplied power supply was totally inadequate. Amazing what cons are around to get the price to look like a good deal.

So, you will have to pony up for the above power supply, so it probably is not such a good deal after all.

 

[lovinthehd]

You just need to know what you're buying and what you may need to buy along with it ?

 

[TLS Guy]

Hi all!

Aiyima A07 PRO amp. I bought one on Aliexpress (good price) about 10 days ago, and it arrived today.

Slight problem - no power unit with the amp, and the user manual warns that it should be used with "the switching power supply of the regular manufacturer".

This is the first time I've ever run into a situation like this - any ideas, suggestions for something that will work ok?

I've already left a message for the seller, but I'll be surprised if that leads anywhere.

Thanks

I had never heard of Aliexpress before, and assumed it was an auction website. I see that amp is new, but it is sold without power supply. The one that Aliexpress have for sale, is not powerful enough for that amp, so no wonder it blows up.

The power supply will cost you more than the amp. This is not surprising as switching power supplies are very complex affairs.

I really don't see how they could make a product like you bought for $52.00 that was any good. So my strong suspicion is that this is a piece of junk well below the standard of usual junk.

I would return it for a refund pronto, as I would expect a very short life indeed from this item.

Junk purchases are the most expensive you ever make.

 

[Eppie]

These units can use different power supplies from 24V to 48V. The Amazon version includes a 36V power supply. The maximum power output of the unit depends on the voltage supplied. You need a 48V supply to achieve maximum rated power but don't rely on their power output figures. They advertise 300W per channel but give no qualifiers, so it is likely peak power. With the 36V supply, the unit actually puts out around 60W into 8 ohms or about 100W into 4 ohms, which is plenty for desktop use.

The amps sell for around $90US (with the 36V supply). If you can get a power supply so that the total cost is around $90 then you can keep the unit, otherwise you may want to return it.

@TLS Guy I'm surprised that you have not heard or AliExpress. For many in the repair trade, it is the go-to site for parts. Much cheaper than Digi-key or Mouser, etc., but there can be long shipping times from China. You have to be careful about counterfeit parts though, when dealing with Chinese suppliers. It's not uncommon for higher value parts like MOSFETs, so some added research is required.

AliExpress has the biggest selection of any supplier and prices can be crazy cheap. It's an aggregate site for thousands of manufacturers and suppliers. I needed a thermal fuse link to repair the power brick for an aquarium pump and no-one in North America had any for this rather old pump. I found one on AliExpress within 10 degrees C and a package of 10 was around $3. Shipping was over 3 weeks though as sometime the parts come by boat.

A better experience was repairing my brother-in-law's old Kenwood receiver (from the 1980's). The output transistors had blown on one channel and there were no replacements in North America and I had a very difficult time trying to find a proper substitute. AliExpress had a supplier with the original parts! 3 matched pairs cost me $5 and they were already in stock at a Toronto warehouse. I repaired that receiver a year ago and it's still working fine.

 

[Kleinst]

These units can use different power supplies from 24V to 48V. The Amazon version includes a 36V power supply. The maximum power output of the unit depends on the voltage supplied. You need a 48V supply to achieve maximum rated power but don't rely on their power output figures. They advertise 300W per channel but give no qualifiers, so it is likely peak power. With the 36V supply, the unit actually puts out around 60W into 8 ohms or about 100W into 4 ohms, which is plenty for desktop use.

The amps sell for around $90US (with the 36V supply). If you can get a power supply so that the total cost is around $90 then you can keep the unit, otherwise you may want to return it.

@TLS Guy I'm surprised that you have not heard or AliExpress. For many in the repair trade, it is the go-to site for parts. Much cheaper than Digi-key or Mouser, etc., but there can be long shipping times from China. You have to be careful about counterfeit parts though, when dealing with Chinese suppliers. It's not uncommon for higher value parts like MOSFETs, so some added research is required.

AliExpress has the biggest selection of any supplier and prices can be crazy cheap. It's an aggregate site for thousands of manufacturers and suppliers. I needed a thermal fuse link to repair the power brick for an aquarium pump and no-one in North America had any for this rather old pump. I found one on AliExpress within 10 degrees C and a package of 10 was around $3. Shipping was over 3 weeks though as sometime the parts come by boat.

A better experience was repairing my brother-in-law's old Kenwood receiver (from the 1980's). The output transistors had blown on one channel and there were no replacements in North America and I had a very difficult time trying to find a proper substitute. AliExpress had a supplier with the original parts! 3 matched pairs cost me $5 and they were already in stock at a Toronto warehouse. I repaired that receiver a year ago and it's still working fine.

Dang, if only I was that talented..... I wouldn't know where to start in repairing items like that.

 

[ra-audio]

You just need to know what you're buying and what you may need to buy along with it ?

Sure. How many TVs, radios, printers, laptops etc. don't have a way of powering them up when they arrive?

 

[PENG]

Hi all!

Aiyima A07 PRO amp. I bought one on Aliexpress (good price) about 10 days ago, and it arrived today.

Slight problem - no power unit with the amp, and the user manual warns that it should be used with "the switching power supply of the regular manufacturer".

This is the first time I've ever run into a situation like this - any ideas, suggestions for something that will work ok?

I've already left a message for the seller, but I'll be surprised if that leads anywhere.

Thanks

I bought my with the amp for a great price, it is the gigantic and much heavier 48 V/5A model:

With amp: $109.99, but I bought it when it was on sale for $88

Fosi Audio V3 300W x2 2 Channel Hi-Fi Stereo Audio Amplifier

If you buy the 48 V brick separately it costs $59, so you can probably do better retuning yours to Aliexpress and buy the Fosi directly from them, or from Amazon.

Fosi Audio 48V Power Supply Adapter for TB10D, BT20A PRO,V3

Those amp works really well, same audio performance as my other amps that costs many times more.

 

[ra-audio]

I had never heard of Aliexpress before, and assumed it was an auction website. I see that amp is new, but it is sold without power supply. The one that Aliexpress have for sale, is not powerful enough for that amp, so no wonder it blows up.

The power supply will cost you more than the amp. This is not surprising as switching power supplies are very complex affairs.

I really don't see how they could make a product like you bought for $52.00 that was any good. So my strong suspicion is that this is a piece of junk well below the standard of usual junk.

I would return it for a refund pronto, as I would expect a very short life indeed from this item.

Junk purchases are the most expensive you ever make.

Really? On Amazon, Aiyima products all have 4 plus stars and no mention of missing power units.

 

[ra-audio]

I bought my with the amp for a great price, it is the gigantic and much heavier 48 V/5A model:

With amp: $109.99, but I bought it when it was on sale for $88

Fosi Audio V3 300W x2 2 Channel Hi-Fi Stereo Audio Amplifier

If you buy the 48 V brick separately it costs $59, so you can probably do better retuning yours to Aliexpress and buy the Fosi directly from them, or from Amazon.

Fosi Audio 48V Power Supply Adapter for TB10D, BT20A PRO,V3

Those amp works really well, same audio performance as my other amps that costs many times more.

Very helpful - thanks. I may just (free) return the unit, it was bought mostly as a low cost standby.

 

[lovinthehd]

Sure. How many TVs, radios, printers, laptops etc. don't have a way of powering them up when they arrive?

I've seen some audio gear like the Aiyima that give you your own choice of usb power supply. It should be clear in the description, agreed. Aliexpress I'm not a customer/user of their site, prefer buying from US vendors/sites.

 

[mono-bloc]

I had never heard of Aliexpress before, and assumed it was an auction website

Aliexpress are what you might call "Cheap and Nasty"They have flooded the Asian market, together with Australia. Selling everything from a leaky bucket to a GPS tracker for $4.50. In short they sell what Amazon rejects. Unfortunately, this is correct for some of the cheap Chinese junk, which is infecting selling sites like E-Bay, These mini-amps all rely on a cheap two dollar plug-in power supply. Some time ago I obtained a few of class "D" offerings They all looked the part with Valves [Tubes] glowing in the darkness. Some worked for a while, some died, and some where dead on arrival. The old saying of "you only get what you pay for" rings true. The power supply will cost you more than the amp Quality power supplies as you say are expensive. Just look what you paid for your Quad power supplies. My main system at the moment is Cyrus. While I have the vintage Cyrus 2, with external power supplies I also have a six box system, with separate power supplies , for the pre and the spinner. Total cost for 2 supplies was close to 6k aus.

 

[Eppie]

Aliexpress are what you might call "Cheap and Nasty"They have flooded the Asian market, together with Australia. Selling everything from a leaky bucket to a GPS tracker for $4.50. In short they sell what Amazon rejects. Unfortunately, this is correct for some of the cheap Chinese junk, which is infecting selling sites like E-Bay, These mini-amps all rely on a cheap two dollar plug-in power supply. Some time ago I obtained a few of class "D" offerings They all looked the part with Valves [Tubes] glowing in the darkness. Some worked for a while, some died, and some where dead on arrival. The old saying of "you only get what you pay for" rings true. The power supply will cost you more than the amp Quality power supplies as you say are expensive. Just look what you paid for your Quad power supplies. My main system at the moment is Cyrus. While I have the vintage Cyrus 2, with external power supplies I also have a six box system, with separate power supplies , for the pre and the spinner. Total cost for 2 supplies was close to 6k aus.

I've been tempted in the past to try some of those cheap Chinese amps. They have all sorts of tube amps/pre-amps and class-D amps available but it's a total "crap shoot". I only use AliExpress for parts that I can't find locally. Some test and repair gear is available too but I would first look for some reliable YouTube reviews. I've seen videos of people trying out class-D modules to build their own amps, and some are actually ok. Just ignore the power specs. Like Aiyima, they typically take a 60W module and claim 300W.

 

[MrBoat]

Aliexpress are what you might call "Cheap and Nasty"They have flooded the Asian market, together with Australia. Selling everything from a leaky bucket to a GPS tracker for $4.50. In short they sell what Amazon rejects. Unfortunately, this is correct for some of the cheap Chinese junk, which is infecting selling sites like E-Bay, These mini-amps all rely on a cheap two dollar plug-in power supply. Some time ago I obtained a few of class "D" offerings They all looked the part with Valves [Tubes] glowing in the darkness. Some worked for a while, some died, and some where dead on arrival. The old saying of "you only get what you pay for" rings true. The power supply will cost you more than the amp Quality power supplies as you say are expensive. Just look what you paid for your Quad power supplies. My main system at the moment is Cyrus. While I have the vintage Cyrus 2, with external power supplies I also have a six box system, with separate power supplies , for the pre and the spinner. Total cost for 2 supplies was close to 6k aus.

Aliexpress is just a way to circumvent US (etc.) middle-pimps of same, that typically double the price just for handling/listing it.

I've had good luck with these small amps. The ones I have all use TI chipsets, Nichicon caps and some other parts that are at or above industry standard. The Fosi BT30D Pro has been in my bedroom system every day for about a year now and has been on 5+ hrs/night. I have others dating back 4 years by now. So far, I have not had to return anything.

The amps in my little JBL active (LSR305) monitors at work are from China and have been powered on continuously since August 2017.

Basically, the Chinese prices are closer to what AI designed, manufactured products should cost, once you remove the glut of parasites that do barely more than breathe on it, that add no value to the product whatsoever. Like the 50+ % that just a regional distributorship (monopoly) will force on it.

Once I found how many so-called domestic products were manufacturing in China, and just pocketing the savings, I stopped caring about domestic/brand loyalties so much.

I treat these things as toys and novelties, or for portable use that I don't have to worry about so much. I gave one to a friend along with a small pair of DIY speakers I made and she uses it daily. If you open the hood to one of these, there isn't a whole lot to go wrong with them. I set one up on a table and my son uses it with his phone to listen to different speakers I have made. They perform much better than I expected and are actually quieter than most household name products I have had.

I have made a few small chip amps. I could troubleshoot and repair these simple circuits if something were to actually go wrong with it, for pennies on the dollar, and all the parts are available here.