NAD M22 Amplifier - Possible to upgrade Amplifier Boards to Newer Model?

[decomo]

Hello,

I have NAD M22 which I really enjoy using but white fume came out of the unit on right channel amp board and it is now not working. (crying).

I took it to local repair shop but he could not fix it because he could not source replacement amp boards for both channels via local NAD authorised dealer. I was told that NAD does not have replacement parts any longer.

If I understand correctly, the amp boards are custom Hypex NC400 customised for NAD by Hypex.

Is it possible to replace NC400 with newer NC500 or NC500X modules and keep the rest of parts such as power supply, Input boards etc?

Any suggestion or idea would be hugely appreciated.

Thank you.

 

[boXem]

NC500 may be possible, NCx500 more complicated.
Suggestions:
1. Contact Hypex support
2. Since the NC400 board schematics are available in the N22 repair manual, a competent repair shop should be able to actually repair the board.
3. Ask advise to @restorer-john

 

[Doodski]

I was able to download the M22 service manual in a very good pdf quality. If you want it let me know and I can email it to you.

 

[decomo]

NC500 may be possible, NCx500 more complicated.
Suggestions:
1. Contact Hypex support
2. Since the NC400 board schematics are available in the N22 repair manual, a competent repair shop should be able to actually repair the board.
3. Ask advise to @restorer-john

Thank you very much. I think that my local repair shop is not competent enough and wasted money sending product and paid for inspection fees and getting the unit back.

What they are said is that those boards are double sided populated by so many surface mount micro components which need special equipment to replace micro components which they do not have. What they told me is that some diodes and transistors are burnt which need to be replaced.

I will also send an email to Hypex Support and @restorer-john if they can help.

 

[Sokel]

How old is your unit?Is pretty bad NAD does not hold replacements,I would think they did.
I mean they know better than that.

I think Hypex will help you.
Under what conditions did it fail?

 

[Koeitje]

How old is your unit?Is pretty bad NAD does not hold replacements,I would think they did.
I mean they know better than that.

I think Hypex will help you.
Under what conditions did it fail?

It was release in 2016 I believe.

 

[Sokel]

It was release in 2016 I believe.

So under the sane 10 year mark,not considering end-of-life date which is the time we start counting backwards.

 

[decomo]

I was able to download the M22 service manual in a very good pdf quality. If you want it let me know and I can email it to you.

Thank you for your kind offer.

How old is your unit?Is pretty bad NAD does not hold replacements,I would think they did.
I mean they know better than that.

I think Hypex will help you.
Under what conditions did it fail?

Not sure what condition it did fail. It was working fine until recently but next day, when powering on, white fume came from right channel power amp module so quickly turned it off. I was told from local repair shop that the board has burnt diodes and transistors which need to be replaced.

 

[RandomEar]

If everything else fails, these still seem to be offered new on ebay (from China). Not sure those are legit, but they do look identical to the ones on your picture at first glance.

You should also make sure that the PSU is still fine. Hopefully, your repair shop checked that and told you exactly what they found. In general, I would expect the PSU to fail first.

 

[decomo]

If everything else fails, these still seem to be offered new on ebay (from China). Not sure those are legit, but they do look identical to the ones on your picture at first glance.

You should also make sure that the PSU is still fine. Hopefully, your repair shop checked that and told you exactly what they found. In general, I would expect the PSU to fail first.

Thank you. Wow. Great to know that there is replacement units. A bit strange that it was offered from China. Is Hypex module designed in EU and manufactured in China?

Re: PSU, I asked this when I picked up the unit, and the technician told me that it seems okay but cannot guarantee because he could not test it long period of time but briefly.
What I remember is that right channel amp board has burnt diodes and transitors and left channel look fine but has distortion when he tested so better replace both amp boards.

 

[RandomEar]

Thank you. Wow. Great to know that there is replacement units. A bit strange that it was offered from China. Is Hypex module designed in EU and manufactured in China?

Designed in the Netherlands, made in Malaysia.

Re: PSU, I asked this when I picked up the unit, and the technician told me that it seems okay but cannot guarantee because he could not test it long period of time but briefly.
What I remember is that right channel amp board has burnt diodes and transitors and left channel look fine but has distortion when he tested so better replace both amp boards.

OK. Gotta try it, I guess. I would be sceptical though, because it looks like both amp boards got damaged at the same time. So a common cause upstream of them sounds plausible.

 

[Wolf11Man]

You could do a nice amp by removing anything inside and installing a matching PSU and amp board. Even better, get some combination, like the ICE power ones. PSU and stereo amp in one. All you have to do is connect mains, input and speaker output.
The sound quality of the NAD is matched by many amp modules out there, only problem they are very cheap to buy.
So if you are no amp building insider, you probably will not believe you can replace or even improve the NAD internals for less than 300$.

PS an ICEpower700AS2 Module around 300$ should be a perfect replacement. Don't worry about "sound". All these amps are 100% perfect.

 

[Sokel]

You could do a nice amp by removing anything inside and installing a matching PSU and amp board. Even better, get some combination, like the ICE power ones. PSU and stereo amp in one. All you have to do is connect mains, input and speaker output.
The sound quality of the NAD is matched by many amp modules out there, only problem they are very cheap to buy.
So if you are no amp building insider, you probably will not believe you can replace or even improve the NAD internals for less than 300$.

PS an ICEpower700AS2 Module around 300$ should be a perfect replacement. Don't worry about "sound". All these amps are 100% perfect.

700AS2 is two generation ago.
A 1200as2 or two brand new Conductor technology 125ASX2 will be much better.

Even better than that is to find a competent technician to diagnose and fix it so he has a chance not to entirely scratch it's potential reselling value.

 

[decomo]

I just opened the lid and took the power amp board out and took some photos. I could not find any components burnt with my own eyes but was told that there are burnt components on the board so I guess that I have to take the word from repair shop.

 

[decomo]

NC500 may be possible, NCx500 more complicated.
Suggestions:
1. Contact Hypex support
2. Since the NC400 board schematics are available in the N22 repair manual, a competent repair shop should be able to actually repair the board.
3. Ask advise to @restorer-john

How old is your unit?Is pretty bad NAD does not hold replacements,I would think they did.
I mean they know better than that.

I think Hypex will help you.
Under what conditions did it fail?

Just got response from Hypex and they no longer have replacement boards and ask repair person to find alternative solutions.

 

[Sokel]

The ones here don't look very healthy:

 

[Sokel]

Just got response from Hypex and they no longer have replacement boards and ask repair person to find alternative solutions.

That's unfortunate.
Even if they don;t have some anymore I would have thought they would offer a fix.
I really thought they were better than that.

 

[decomo]

The ones here don't look very healthy:

Wow. you have really good eye. It actually reminds me that repair person briefly mention about D25 when I spoke to him over the phone earlier today.

 

[Sokel]

Wow. you have really good eye. It actually reminds me that repair person briefly mention about D25 when I spoke to him over the phone earlier today.

Can you post some pics from the PSU too?

 

[decomo]

Can you post some pics from the PSU too?

Certainly. Here they are. To me, it looks clean and I do not see any surface mount components on PSU unless they are populated bottom side of PCB.