Reliability of cheap class D amplifiers

[alfarn]

I like the general idea of cheap chi-fi class D mini amps. Most/all of them have enough power for my needs (nearfield listening at desktop), many of them measure well here on ASR, and the small form factor is a plus. A bare-bones amplifier with only RCA inputs like the the Aiyima A07 sounds perfect to me, in theory at least.

However, the number of people reporting units that were either dead on arrival or broke after a very short time is a huge turn off for me. I have to order these amps from abroad and don't want to go through the trouble of shipping a defective unit back overseas. It seems to me that all of these amplifiers have poor quality control, but I don't have the complete picture. Is there any amplifier that has proven to be more reliable than the rest or do I just have to accept the risk if I buy a cheap class D mini amp?

 

[TonyJZX]

define cheap

for sub $100 you roll the dice... IMO if I'm spending $100 I hope it lasts the warranty.. if it fails at the 18 month mark well then... i can take it... and even then there's people who have 3 month old units that failed and they still get grief... because that's the way they are

buy off amazon? or there may be a local dealer... there are a few topping smsl type dealers here but I reckon the 'fish rots from the head'... if topping smsl give the dealer the run around then i dont expect good end service either... i scarcely think that if topping smsl screw the local dealer, they're gonna shield me from that general lack of business 'morality'

I feel like at $200-$300 or more you should get better build quality but that remains to be seen.

While some of us think Sabaj smsl topping are 'better' than the stuff down below like aiyima fosi, I question that too.

 

[fpitas]

I would simply buy from a reputable vendor (like Amazon?) that allows return/refund. I doubt anyone spends a lot of time on QC for dirt cheap amps.

 

[TheWalkman]

Over the past fifteen or twenty years, I’ve owned probably a dozen Class Ds (Tripath, Lepai, multiple Aiyimas - A04s, A07s, Pros, etc., Topping,, Audiophonics, etc.) I’ve never had a single problem with a Class D.

i think a few people who have had problems (like the apparent bad batch of Topping amps) have been very vocal and are giving them all a bad reputation.

Buy a $75 Aiyima AO7, plug it in and enjoy it.

 

[JktHifi]

I have class D amp inside my Yamaha soundbar. It’s still alive untill now. Bought 7 years ago. I think reliability not defined by Class D or AB.

 

[fpitas]

I have class D amp inside my Yamaha soundbar. It’s still alive untill now. Bought 7 years ago. I think reliability not defined by Class D or AB.

True. I think OP is talking about the $15 amps you see on eBay, for example. Nobody will bother to QC a thing like that. You're lucky if it works.

 

[alfarn]

I have class D amp inside my Yamaha soundbar. It’s still alive untill now. Bought 7 years ago. I think reliability not defined by Class D or AB.

I agree that reliability should not be equated with the amplifier class. I am more specifically concerned with the cheap chi-fi amps that are very popular these days. They happen to be class D.

 

[Astoneroad]

True. I think OP is talking about the $15 amps you see on eBay, for example. Nobody will bother to QC a thing like that. You're lucky if it works.

I've owned a few Topping & SMSL DACs and amps and have never had an issue. Being the tight wad that I am, I think the fact that such great sound is derived from a $200 solution, makes it sound even better to me and hasn't felt like a gamble... but maybe I'm just "Lucky"... lol.

 

[alfarn]

define cheap

for sub $100 you roll the dice... IMO if I'm spending $100 I hope it lasts the warranty.. if it fails at the 18 month mark well then... i can take it... and even then there's people who have 3 month old units that failed and they still get grief... because that's the way they are

buy off amazon? or there may be a local dealer... there are a few topping smsl type dealers here but I reckon the 'fish rots from the head'... if topping smsl give the dealer the run around then i dont expect good end service either... i scarcely think that if topping smsl screw the local dealer, they're gonna shield me from that general lack of business 'morality'

I feel like at $200-$300 or more you should get better build quality but that remains to be seen.

While some of us think Sabaj smsl topping are 'better' than the stuff down below like aiyima fosi, I question that too.

For me cheap is under $150, like the Loxjie A30 ($140 on Amazon) which I was intrigued by at first but later got turned off by all the negative reports about defective units.

I don't mind paying a little extra for a more reliable product. I love the idea of the Aiyima A07. Are there any other bare-bones amps like it on the market?

 

[alfarn]

Over the past fifteen or twenty years, I’ve owned probably a dozen Class Ds (Tripath, Lepai, multiple Aiyimas - A04s, A07s, Pros, etc., Topping,, Audiophonics, etc.) I’ve never had a single problem with a Class D.

i think a few people who have had problems (like the apparent bad batch of Topping amps) have been very vocal and are giving them all a bad reputation.

Buy a $75 Aiyima AO7, plug it in and enjoy it.

Good point about the people having problems being vocal. I'll give the Aiyima A07 some more thought. What's your experience with the power supply that comes with the amp? I've read that you have to be specific in how you connect the power supply and amp, since otherwise you can damage the power supply. Seems a bit inconvenient for a consumer product, but I guess one can live with it given the price of the amp.

 

[TonyJZX]

i think we are obviously talking about chinese class d units

at this point, just buy the A07 and experiment with psus... the chances of you getting a crap unit is slim and there's such a wealth of knowledge even here you cant really lose

i have an smsl a300 and its $200 and it too has its share of returns.

I personally dont consider the A07 to be of merchantable quality is some western markets due to its behavior... but if you can accept that its a sub $100 amp with some strange quirks but good performance and massive power then you may as well try it.

 

[TheWalkman]

Good point about the people having problems being vocal. I'll give the Aiyima A07 some more thought. What's your experience with the power supply that comes with the amp? I've read that you have to be specific in how you connect the power supply and amp, since otherwise you can damage the power supply. Seems a bit inconvenient for a consumer product, but I guess one can live with it given the price of the amp.

As I recall, I decided not to press the A07 with 48 V supplies, but, instead, am running a 36V supply, instead. Though I did, “upgrade” to a Mean Well power brick (in his review, Amir got spooked with the stock supply) but to be honest, I’m not sure this makes a huge difference In volume or sound quality.

I’m currently using the Aiyimas to amplify streams from an Amazon DOT and also from my TV so the audio quality is fine and loud enough for me.

 

[wwenze]

Never had a single class D amp fail... And my mom even dropped one from over a metre, and that thing has a toroidal transformer inside

If anything it feels like the capacitors of computer speakers using class AB amps tend to die faster, and the heat isn't helping.

The switchers and rectifiers of an SMPS, as well as the bridge rectifier of a 50Hz power supply, these I certainly see dying more often than the amp transistors. Depends on whether you want to call that part of the amp or not. Those ebay amps are usually using external power adapters so if you don't include the power supply they can last forever, but if you include the power supply in the complete setup then those don't last very long. My fibre optic modem is already on its third power supply after it killed the first two, geez.

I like the general idea of cheap chi-fi class D mini amps. Most/all of them have enough power for my needs (nearfield listening at desktop), many of them measure well here on ASR, and the small form factor is a plus. A bare-bones amplifier with only RCA inputs like the the Aiyima A07 sounds perfect to me, in theory at least.

However, the number of people reporting units that were either dead on arrival or broke after a very short time is a huge turn off for me. I have to order these amps from abroad and don't want to go through the trouble of shipping a defective unit back overseas. It seems to me that all of these amplifiers have poor quality control, but I don't have the complete picture. Is there any amplifier that has proven to be more reliable than the rest or do I just have to accept the risk if I buy a cheap class D mini amp?

The product themselves are usually fine... it's the shipping. Usually just the product box itself plus lots of wrapping. No DHL box or Amazon air bubbles that kind of luxury. Computer tablets arrive bent. If your product survives the shipping it is usually fine afterwards.

 

[Joe Smith]

I am still using SMSL SA-50 amps that I purchased about 10 years ago, and no problems. They work as fine as ever.

I built a ton of 3116 board amps about 7 years ago (mostly for fun, SMSL was slow to make a device with the 3116 chip) - again no problems, apart from one static zap to a CD player that was due to my having stupidly used a metal volume knob...got static off the carpet walking over to the unit...but not the amp's fault.

I have the Aiyima A04, A07 and SMSL AO100 in current use...no problems. The bluetooth was a little odd with the AO100 at first, but then it resolved.

I use the Aiyima 32v/5a power supply for both the A04 ann A07, and it's more than enough.

I think the heat build up and effect on caps could be a bit more worrisome for people who are really pushing the power supply up to the top of what the amp is spec'd for...bad practice in general, I think. If you want/need 100 wpc in a class D, the Aiyima is not the way to go. If more like 40 watts for 8 ohms is OK, then it is an excellent way to go. Well-behaved, no power on or power off pops. I think the channel balance is OK at lower volume levels, some have reported inconsistencies; they must be more sensitive to that than I am, or I'm lucky in the one I got. It's true that the power supply likes to be plugged into the unit first, then to the wall, as it can spark if you do it the other way.

I don't like to add to electronic waste, but my experience with the Chinese-made amps has been very good. For most of us on this board, $90 is not a big deal if there is an "early" failure. None of these devices will last as long as the amps and receivers made in the 70s, that's just the way of things now.

I think the main thing is to consider your power needs carefully and then pick the right model for you so you get the right one the first time. If needing higher power, among others, the SMSL AO200 or A300 are good current choices. Or for more, step up to a Hypex 252.

Have fun with cheap class D!

 

[Kegemusha]

I have an smsl as "soundbar" replacement in the kids room, for more than 7 years an no an issue, of course this AMP is not measuring good at all but for TV is ok.

 

[YesChickenNuggets]

I like the general idea of cheap chi-fi class D mini amps. Most/all of them have enough power for my needs (nearfield listening at desktop), many of them measure well here on ASR, and the small form factor is a plus. A bare-bones amplifier with only RCA inputs like the the Aiyima A07 sounds perfect to me, in theory at least.

However, the number of people reporting units that were either dead on arrival or broke after a very short time is a huge turn off for me. I have to order these amps from abroad and don't want to go through the trouble of shipping a defective unit back overseas. It seems to me that all of these amplifiers have poor quality control, but I don't have the complete picture. Is there any amplifier that has proven to be more reliable than the rest or do I just have to accept the risk if I buy a cheap class D mini amp?

I bought an a07 a while back based on recommendation of ASR, it sounds great to me, but I must report that quality control is dangerously inadequate. Loose solder balls, metal shards from heatsink milling/boring.

If you do buy one, DO NOT PLUG IT IN, take it apart, remove the heatsink, motherboard, do a thorough inspection for loose metal. You'll need magnifying glass and tweezers.

 

[sound67]

After some years of not running a bedroom stereo system I got back into the game and have tried these Class D amps so far:

1. Aiyima T9 hybrid amp. No issues while I had it, except a BT "uncoupling" problem. Which is why I sent it back and replaced it with the
2. Aiyima T9 Pro hybrid amp. BT "uncoupling" issue has been resolved on this unit. No noise, no clicking sounds, no other issues. - so far. I'm still using it, with the 32V-5A laptop power supply it came with - which so far shows no problems.
3. Nobsound B100 hybrid amp. I was intrigued by its 4-tube preamp section and a second RCA analogue input. Unfortunately, it never worked: Once ANY source (even BT) was connected, I had a persistent humming sound on for which I found no solution. And since the power supply, which seems to be the problem, is INSIDE the unit, I could not try a different one. Contacted Nobsound/Douk Audio's customer support (who were very friendly and tried to be helpful), and they came to the same conclusion that it was a faulty unit. Sent back promptly.
4. Loxjie D30, D-class. No issues, no noise, enough power, smooth operation - for three weeks. Then, suddenly, the volume output for the sub dropped off sharply, and the switch between EQ modes now produced a loud "bump" sound every time. Sent back today.
5. Aiyima D03, D-class. Just ordered.

 

[Hapo]

...I am having good luck so far with an SMSL A300 I bought to replace a well-used and still perfect Aiyama A07 to get a sub out and more inputs...

...I am a serious cheap skate and do not resent the few extra $$$ it was...

...it seems pretty upscale compared to the Loxjie A 30...(I sent mine back w/o auditioning it)...

...the display symbols on the SMSL A 300 are a bit weird @ blue tooth and USB but it's not like you can't tell what they mean...

 

[grogi.giant]

What's wrong with those? BT, USB, OPT, COA ?

 

[JSmith]

chi-fi

Please try not to use that term;

Let's Avoid the Term Chi-Fi

I often see the use of the term "Chi Fi" to describe audio products from China. I see the intention and don't think anyone is trying to be racist and what have you. Still, I like us to show the highest respect to products from around the world. As avid readers of this forum know...

www.audiosciencereview.com

JSmith