Class D amp long term reliability

[Koeitje]

I bought my NC400's second hand a couple of years ago and they are still going strong. Just remember that people that have issues are more likely to post about them.

 

[Jukka]

I've been using a pair of NC400 mono blocks for 7 years now and they still work, inspite that I assembled them myself

I'll set an alarm to 3 years from now and reply here the status then.

 

[theREALdotnet]

I've been using a pair of NC400 mono blocks for 7 years now and they still work, inspite that I assembled them myself

Perhaps you’re not giving yourself enough credit

 

[Petrushka]

Is there any discussion of metal whiskers?

 

[goryu]

Here is my experience: I bought a used VTV nc1200 amp 3 years ago. Unfortunately, it was early production and the channels weren't inverted as they should have been. Rather than send it back, I made the change myself. The amp worked great for 3 years until I recently switched to Acoustat speakers from Magnapan Tympani IVa's, After a few weeks, the amp failed. I contacted VTV and they had me ship it back for repair. About 10 days after shipping, it arrived. One amp module was replaced and VTV checked it all out on their AP and everything tested fine. It worked for about 2 days then went out again. I shipped it back a second time, they replaced the new module with another, tested it again, and sent it back to me within a week. They told me they had never had a new module fail before. It has been working fine now for several months. I paid shipping to VTV and for the first module, they didn't charge me for the 2nd module or for the return shipping.

I would highly recommend buying products from your country of residence. Shipping back and forth internationally has gotten crazy expensive. These Hypex and Purifi amps nearly all have the same modules and power supplies. The main differences are cosmetic with the exception of the input boards, which are all roughly similar. If cosmetics and small feature differences are important, then buy from overseas forewarned that shipping, etc., is not going to be cheap and factor that into your decision.

 

[theREALdotnet]

Is there any discussion of metal whiskers?

Is this left as an exercise to the reader, or are you going to explain?

Pardon my ignorance.

 

[Doodski]

Is there any discussion of metal whiskers?

We have discussed whiskers in previous posts and I posted images from of whiskers from NASA etc

 

[NTK]

Is there any discussion of metal whiskers?

The problem with tin whisker growth (for lead-free solder and lead-free tin plating) is hardly specific to class-d amplifiers.
Here is a post with more information on tin whiskers.

Lead-free solder and audio quality.

Old one that still works is a comfort. My comfort food when I am soldering interconnects is "Silver" solder. I have a good stash of it (meaning "old) ...The biggest curse in audio is our age... I would call that a blessing... but that is my imo and respect that ymmv.;) Also the higher...

www.audiosciencereview.com

 

[dlaloum]

The problem with tin whisker growth (for lead-free solder and lead-free tin plating) is hardly specific to class-d amplifiers.
Here is a post with more information on tin whiskers.

Lead-free solder and audio quality.

Old one that still works is a comfort. My comfort food when I am soldering interconnects is "Silver" solder. I have a good stash of it (meaning "old) ...The biggest curse in audio is our age... I would call that a blessing... but that is my imo and respect that ymmv.;) Also the higher...

www.audiosciencereview.com

It has been a major problem in many old data centers, where the floor tiles (and some older rack frames) included Zinc in the underside coating - over the years the zinc would oxidise creating whiskers - the AC/Ventilation would then carry the whiskers into various devices power supplies, resulting in massive BANGs.

 

[Alice of Old Vincennes]

A few thoughts from me.
- Contact Hypex.nl and ask them to help with a cost-effective solution.
- The shipping costs seem disproportionately high to me. The defective board can definitely be sent back and forth for under €100.
- Also ask Audiophonics to find a cost-effective solution, perhaps together with Hypex.

Once you have worked through the above points, you can create a friendly but firm thread on ASR and DIY and look for someone in the USA who can repair Hypex modules.
An honest and neutral description of the situation could help motivate Hypex to create a uniform warranty and repair solution for the USA and other continents.
The Hypex modules and amplifiers are also well known in the USA.

Maybe @Hypexsales is reading this....

Effort sounds like a full time unpaid internship. Buy from Sweetwater. They repair. All the foreign stuff that must be shipped overseas is disposable. Unless you buy a 1-800 extended warranty with call center operator trained to say no in a foreign language.

 

[Doodski]

For those not familiar with whiskers here is the NASA Goddard web page on the topic.

NASA Goddard Tin Whisker Homepage

 

[Petrushka]

Whiskers are not specific to class D, I just wondered if the problem is considered. It would seem to be more of a problem as circuits get more compact.

 

[antcollinet]

Whiskers are not specific to class D, I just wondered if the problem is considered. It would seem to be more of a problem as circuits get more compact.

Of couse it should be considered by all manufacturers of any electronic equipment. Only the individual manufacturers know if (and to what extent) it is taken care of for their products though.

 

[Petrushka]

Of couse it should be considered by all manufacturers of any electronic equipment. Only the individual manufacturers know if (and to what extent) it is taken care of for their products though.

I’m just wondering if we’ve reached a point where five years is the expected lifetime of equipment, and stuff is considered disposable. It’s interesting that reviews don’t mention this.

 

[NTK]

I’m just wondering if we’ve reached a point where five years is the expected lifetime of equipment, and stuff is considered disposable. It’s interesting that reviews don’t mention this.

Reliability testing is a whole different game. First, even with accelerated testing, the tests will take a long time and specialized equipment, e.g. environmental chambers, shake tables, controlled power sources, etc. Second, you will need to test a large number of samples from different production batches to get any statistical confidence. Third, when there is any change in the manufacturing, which happens often, the test results are no longer valid.

It is simply not feasible for a product review site such as this one to give any kind of meaningful reliability assessments which they are able to defend when challenged (i.e. not guesses).

 

[antcollinet]

It’s interesting that reviews don’t mention this.

How would you expect them to review the reliability of a product?

 

[theREALdotnet]

How would you expect them to review the reliability of a product?

Easy. Amir just hangs on to every reviewed device for, say, 20 years, turns them all on regularly and tests their function and measurements every 2-5 years. Done.

 

[ahofer]

Just checking in to say that my March Audio Hypex p252 purchased in 2019 is still going strong as I type this, after three relocations, and stored in a somewhat climate-variable location.

 

[restorer-john]

Easy. Amir just hangs on to every reviewed device for, say, 20 years, turns them all on regularly and tests their function and measurements every 2-5 years. Done.

Just don't ask him about his TOTL ML (Mark Levinson) power amps...

 

[theREALdotnet]

Just don't ask him about his TOTL ML (Mark Levinson) power amps...

You mean the M50? Or is there something more TOTL? The M50 looks puny next to a Halcro DM88

From what I hear, the Halcro also has superb reliability.