Class D amp long term reliability

[Chrispy]

If we were only as concerned with all the other consumer stuff's longevity/disposability.....how many cars have you guys gone thru?

 

[antennaguru]

If we were only as concerned with all the other consumer stuff's longevity/disposability.....how many cars have you guys gone thru?

A lot, but I endeavor to get 300K miles out of each.

 

[mhardy6647]

Why bother? It's a $100 module. Class D modules were destined for the landfill when they were designed/built. Just remove and replace...

I do hope this is just trolling, sarcasm, satire, or irony.

 

[pma]

I do hope this is just trolling, sarcasm, satire, or irony.

I am afraid that it is not and that it represents opinion of many members.

 

[Trell]

I am afraid that it is not and that it represents opinion of many members.

For those without the skills and needed equipment for diagnosis and repairing, the only other choice is then to send it to someone for repairs. That will quickly cost more than the replacement for many devices, like a $100 device.

The pressure on the manufactures should be to make more reliable devices so that fewer of them prematurely is dumped on a landfill but that will increase the costs.

 

[antennaguru]

I ordered another $100 Class D IcePower module - primarily because of the investment I had already made in the casework, connectors, and layout for the original IcePower module. It is an unfortunate irony, but IMO the most expedient and lowest frustration path.

Sure, I have the ability to remove the module, cut the semi-flexible glue with an Exact-knife, desolder the two large caps, and test them on my LCR-meter, but that will probably take the better part of an hour and that glue will cause aggravation, and cursing out loud while I'm doing it. I also frankly doubt that's the problem because there are so few hours on the module, and then the trouble-shooting expands to the rectifiers and wastes even more time - probably ending in more aggravation because it's most likely IMO a glitch with an un-obtanium part. OTOH, the good things about just replacing the module as the first step is that I eliminate a bunch of aggravation, and the replacement module is so easy to install as the case and board connectors were designed for that module. The good news is that the module is still available, and still only $100 shipped! If it wasn't, I would probably re-design the casework and put a heatsink inside, plus a toroidal transformer with an LM1875 chip amp - which IMO is infinitely more reliable and around the same power output and efficiency into 8 ohm speakers. In either case, I would feel it's a shame to just abandon the casework I already have. There is also a value on time, which is precious, so saving time has value.

In the case of the two Class D plate amps I also had fail, replacements were no longer carried by the manufacturer and I had to buy generic plate amps from Parts Express - which of course were a different size/shape than the OEM plate amps, and none of the hole patterns were the same. I had to make sheet metal filler plates, seal the old holes in the wood composite cabinet, drill new holes for the replacement plate amps with the filler plates, and put RTV sealant all over the place to get it airtight - and which will be a hassle to remove next time.

Of the 6 Class D amplifiers I have owned exactly 3 have failed in 5 or so years - which is a short-term failure rate of 50%. I have no doubt that over a longer term there will be a 100% failure rate. Time will tell if the other brands of Class D modules and plate amps are any longer lived - but I personally doubt it, and am personally happy to use cheaper modules with SINAD that is slightly worse on an AP - but not any worse from an audibility standpoint with my ears.

 

[EJ3]

In all of my stereo equipment that uses Class AB (2 receivers, 1 integrated amp, 2 preamps and 7 amplifiers). from 1973-Today I have had precisely 1 failure of one amplifier channel and that failure could not be attributed to the amplifier itself but to a home electrical system power surge from an outside source. I still own and use all of the stereo items that I mentioned.

 

[rdenney]

In all of my stereo equipment that uses Class AB (2 receivers, 1 integrated amp, 2 preamps and 7 amplifiers). from 1973-Today I have had precisely 1 failure of one amplifier channel and that failure could not be attributed to the amplifier itself but to a home electrical system power surge from an outside source. I still own and use all of the stereo items that I mentioned.

I wish that were true in my case—I really loved the big Spectro Acoustics amp I had back in the day. Now, my cheapie Samson Servo 500 is also acting up, but it didn’t release its magic smoke as dramatically as the Spectro Acoustics. AB topology in both cases.

Rick “whose new Buckeye is waiting for him to return home” Denney

 

[pseudoid]

I have a 10 year old Rotel RMB-1565, ClassD (IcePower) 5-channel amp, that has been pumping out music 24/7, continuously .
Although my purchase was planned for its use as a 5-channel configuration; I heard my ears tell me that they were perfectly happy with 2-channel stereo.
In the intervening years, I have swapped out the L/R input pairs between the 5 channels about 7 times.
It could be snake oil, but I figured if caps are anything like muscles, each of the 5-channels'e circuitry will need equal amounts of exercise… could music be like muscle food???

 

[sigbergaudio]

Great news. The stars have aligned for us! Amir has agreed to do the extra visual inspections after amp operational testing is complete. Many thanks to @amirm and @restorer-john for taking on this extra work. Now we just wait for the amp to make its way from the “to do stack” to Amir’s Test Bench.

What happened with this? The amps are reviewed now, right?

 

[pseudoid]

Amir has agreed to do the extra visual inspections after amp operational testing is complete.

Arrrgh... will there be a pre-instrumentation "shake" test coming soon to weed-out loose screws (etc.) in DUTs?

 

[antennaguru]

What happened with this? The amps are reviewed now, right?

Yes, this will be interesting. Though I think it would also be interesting to see more forensic analysis of failed modules. The challenge will be that some failed modules will be sent in under warranty, and then the failure analysis becomes secret.

BTW, I am happy to send my failed IcePower 50ASX2 module for forensic analysis, even though there is nothing I can see visibly wrong with it, but I'm not sure anyone wants to devote the time on such an inexpensive model Class D module that failed - as there is a lot more interest today in the more expensive Class D modules from Hypex and Purifi.

 

[AdamG]

What happened with this? The amps are reviewed now, right?

Yes done and a tear down thread was posted. Amir disassembled the amp build as far as he was comfortable. He did not remove any of the modules. One of the takeaways was the area where the Hypex module is mounted is painted. @Buckeye Amps has agreed to have this area of the Amp case to remain unpainted to permit improved heat transfer to the case metal from the amp module. @Rick Sykora has also done his own inspection write-up and communicated his findings to Buckeye and posted about his observations in various Buckeye Nc502mp Threads.

Here is Amir’s Teardown inspection:

Buckeye Hypex Nc502mp Multichannel Amp Teardown

I recently reviewed the Buckeye Hypex hypex Nc502mp based multichannel amplifier. This is a quick teardown review of the same. The case is easy to open after which, you see the implementation based on three Hypex stereo NC502MP class D amplifiers with integrated switching power supplies...

www.audiosciencereview.com

 

[pma]

This is nice but not sufficient to answer the issue that @restorer-john addressed in his post #54. PCB and Al base bent and MLCC failure/explosion.

 

[AdamG]

This is nice but not sufficient to answer the issue that @restorer-john addressed in his post #54. PCB and Al base bent and MLCC failure/explosion.

Agreed. The reported failure area was not directly inspected as no one involved wanted to break down the new module. It would probably void the Hypex warranty and I was not willing to permit that amount of disassembly. So we did as much non-destructive disassembly as possible.

 

[EJ3]

very real benefits to customers in terms of performance, reliability and utility with these newer manufacturing techniques.

Hold on a moment, as I see it: the lack of reliability, the lack of schematics & the lack of ability to get the parts to repair seems to me to be the discussion here. This discussion would not be happening at all if they were reliable.

 

[EJ3]

For audio components though, shoving an entire system into a single box at lower cost in my opinion just makes sense. These products can have long life spans and overall consume less than what I guess you would call more traditional and less integrated components. Having an extra rack with a class AB amp, pre-amp, digital front end, whatever else isn't in some way virtuous when you could have an integrated amp with DSP that lasts 20 years (if you want it to). Traditional electronics can be disposed and upgraded just as easily as any others, so I don't think that solves consumerism.

I feel exactly the opposite way. If anything in my system goes down, in the time it takes me to re-route some of the wires, or replace one of the pieces with another that I have on hand, I am up & running my stereo again. Then I can diagnose & repair (or have someone else diagnose & repair) whatever it is that failed at my leisure. Anything that is in my system, I have another (it may not be the exact same make or model [but it can take over the function of the now non-working unit]). I started doing this in my teen years: that if I buy something and I like it: when I finish paying for the first one, I buy a second one so that I will have it when (not if) I need it. This goes for shoes, other clothes, audio gear, cars, homes, etc. example: My wife & I have one car each. And we own a third car for when one is in the shop. So we have a 2000, a 2007 & a 2012. When we sell one, we will buy another. The likelihood of us being inconvenienced by not having available transportation is slim. Everything we have, we own. Not us & the bank, us & the credit card company or us & anyone (except for the property tax aspect). And if you think you actually own your home: try not paying the property tax & you will find out who really owns your home. There are very few places that don't have property tax on your home.

 

[restorer-john]

I feel exactly the opposite way. If anything in my system goes down, in the time it takes me to re-route some of the wires, or replace one of the pieces with another that I have on hand, I am up & running my stereo again. Then I can diagnose & repair (or have someone else diagnose & repair) whatever it is that failed at my leisure. Anything that is in my system, I have another (it may not be the exact same make or model [but it can take over the function of the now non-working unit]). I started doing this in my teen years: that if I buy something and I like it: when I finish paying for the first one, I buy a second one so that I will have it when (not if) I need it. This goes for shoes, other clothes, audio gear, cars, homes, etc. example: My wife & I have one car each. And we own a third car for when one is in the shop. So we have a 2000, a 2007 & a 2012. When we sell one, we will buy another. The likelihood of us being inconvenienced by not having available transportation is slim. Everything we have, we own. Not us & the bank, us & the credit card company or us & anyone (except for the property tax aspect). And if you think you actually own your home: try not paying the property tax & you will find out who really owns your home. There are very few places that don't have property tax on your home.

My Dad always said if you have a spare, you'll never need it. All about outwitting that old b#stard Murphy's Law. I took it to a whole new level (and have the storage sheds to prove it).

Without the schematic, but with a bit of help IDing a few components, I'm almost done repairing the vaporized Hypex NC-252MP I showed in an earlier thread. I'm doing it just for fun, to hopefully prove that it can be done.

 

[EJ3]

I remember when Japanese cars became really popular and everyone complained about how hard they were to be worked on. And then the people stopped complaining about that because it was so rare that you had to actually work on them.

I currently own a 2000 Nissan Frontier, a 2007 Honda & a 2012 Lexus These vehicles are not out in the elements when they are at home. The 2000 Nissan & the 2007 Honda will likely make 200K. The Lexus currently only has 31K on it & has several computer failures (not fatal to the car yet) but will soon cause it to need a new main computer. At this time, I can still get one. But, based on this ones history (and going by time), I will need another computer for it in 9 years (or less), when the car will likely have 130K on it & the computer will be made of unobtanium at any price. I do not foresee the Lexus making 200K. In addition to that, the annual expense of the maintenance (even though there was less of it) for these three vehicles has been much more than my former USA & German cars. The Lexus is what tipped that away from being about the same as the former vehicles. Hopefully the next vehicle we buy will be a USA or German brand again.

 

[MakeMineVinyl]

Hold on a moment, as I see it: the lack of reliability, the lack of schematics & the lack of ability to get the parts to repair seems to me to be the discussion here. This discussion would not be happening at all if they were reliable.

When was the last time you had the motherboard of your desktop computer fail? These rarely do, and the SMD assembly is if anything more intricate than on an audio amplifier PCB. I'm around thousands of amplifiers daily and the number which come back for service could probably be counted on one hand over the course of a month. I can't speak to the reliability of other brands, but ours is impeccable.

As to the schematic issue, that is mostly due to liability issues. The minute a schematic is included, that is a tacit license for the consumer to attempt home repairs. Parts are the same, however we routinely ship replacement amplifier modules to customers.