Trouble with Nord
- Thread starter Drzoigberg
- Start date
mikeyb
pfm Member
Done
Might be worth joining and so posting there so it doesn't start any inter forum fighting
Arkless Electronics
Trade: Amp design and repairs.
SMPS are nowhere near as reliable as standard ones, vastly more complex, and a total **** to repair when they do go wrong....
The same applies to class D amps, which are in effect SMPS with the output voltage modulated by the music!
of the two the SMPS is a bit more unreliable due to the higher voltages though.
The same applies to class D amps, which are in effect SMPS with the output voltage modulated by the music!
of the two the SMPS is a bit more unreliable due to the higher voltages though.
Arkless Electronics
Trade: Amp design and repairs.
Whilst SMD doesn't help matters the main issue is the same as its always been with mains SMPS ie that it either works perfectly or literally goes bang and explodes shrapnel of bits of mosfet etc in yer face! There is very little in between. Hence when repairing them you may have replaced say 10 parts that are definitely blown but if there is one part that looks OK, measures OK on a DMM, but is dodgy under load then 9 times out of 10.. BANG!!!! and everything you've just replaced has been blown up again.... It HAS to be perfect at that moment you switch it on.. no if's no but's... worse still, as they deal with rectified and smoothed mains @ 340V there is no practical way, once you've checked everything that you can, that you can be sure all the parts are going to handle 340V other than actually switching it on to test it...
Worse still... you can't measure any of the voltages for diagnostic reasons unless it's working... catch 22!
Shadders
pfm Member
Hi,
I would not go down the route or changing components yourself, as if you pursue the warranty claim, this will invalidate it. The vendors should never tell any customer to change any component. You could get it repaired by a third party if there is no response from the company responsible, and then reclaim the money through the small claims court :
https://www.gov.uk/make-court-claim-for-money/court-fees
Regards,
Shadders.
I would not go down the route or changing components yourself, as if you pursue the warranty claim, this will invalidate it. The vendors should never tell any customer to change any component. You could get it repaired by a third party if there is no response from the company responsible, and then reclaim the money through the small claims court :
https://www.gov.uk/make-court-claim-for-money/court-fees
Regards,
Shadders.
hifinutt
hifinutt
I often look at audioshark and was thinking of posting this. There does seem to be a lot of love for nord. Actually the sugden anv 50 , pass xa 25 and nord up are on my bucket list to try. This has rather put me off , you don't hear this about sugden. They still look after amps decades old with no problems. Recently had a 4 year old a21se go back to them and they were golden . Aftercare is paramount to me
Timcat
pfm Member
I have been using NC500 based amps for nearly 4 years. Mine are Acoustic Imagery ATSAH 500s, but they use the same Hypex amplifier (NC500) and power supply boards (SMPS1200A700) as the Nord amps. I have 5 of this amps, they are mono blocks, and the power supplies have had to be replaced in 4 of them because of component failure. The issue with mine has been the failure of the inrush current limiting thermistor. The PSUs did continue working, as this component only functions during switch on, but its failure is fairly exciting, as it partially explodes with a bright flash. This is a known fault.
I only mention this because, whilst I like these amps (a lot!), I think that there are issues with the power supply boards.
Fortunately, they are not too difficult to replace, they simply plug in, and cost about £200 each. see https://www.hifisound.de/Do-it-your...-Supply/Hypex-SMPS-1200A700-Power-Supply.html
I only mention this because, whilst I like these amps (a lot!), I think that there are issues with the power supply boards.
Fortunately, they are not too difficult to replace, they simply plug in, and cost about £200 each. see https://www.hifisound.de/Do-it-your...-Supply/Hypex-SMPS-1200A700-Power-Supply.html
lazycat
pfm Member
Drzoigberg
pfm Member
I think this is a little unfair, I am backed into a corner with this, I certainly wish it was resolved differently and this thread was not needed.
Drzoigberg
pfm Member
Out of 5 amps 4 power supplies have been replaced due to catastrophic failure over only 4 years ??
I don’t quite know what to say
Maybe a thread on how to build a transformer based power supply !!
Drzoigberg
pfm Member
Hmmm and another thing £800 in cost, this is not your fault or responsible if it is a know fault,
This is all so frustrating, these amps sound amazing
Timcat
pfm Member
I should have clarified; Acoustic Imagery replaced all four of the failed power supplies free of charge. John Young of Acoustic Imagery actually came to my house and did the work for me on the spot.
The reason I looked up the replacement cost is that one of the power supplies has blown its thermistor recently (it is now out of guarantee) and I was wondering how much it would cost for me to replace it. The amp is still working, so I will keep using it until it stops working.
Would I buy another Hypex based amp? Difficult question, one needs to balance their relative cheapness (they cost about £1,500 for a pair) against their unreliability. OK £1,500 is not a small sum, but my choice boiled down to the Hypex amps v. a Bryston at over £5k and the Hypex amps sounded better (to me).
sq225917
Bit of this, bit of that
It's unfair that you've been treated so badly, I was highlighting a possible route to getting a resolution. Squeaky wheel and all that...
Drzoigberg
pfm Member
I do wish this didn’t have to happen, the analogy for my line of work as a landlord is telling someone who returned there pint that we’ve had a couple of dodgy pints before out of that barrel, but it’s ok you can buy another of the same to replace it.
However on a brighter note Colin has been in touch and hopefully this can finally be resolved.
Darth Vader
From the Dark Side
I don't know this power supply but from the OP description it comes across as if the smoothing capacitors had gone leaky and needed to be reformed. This happens when electrolytics have not been used for a while. There is an electrolytic action that forms a film that is necessary for the cap to function. Left idle this degrades and the cap becomes leaky i.e. passes a very large current that pulls the supply rail down. This may result in a bang. However if the current has been limited then after a while the lost film is reformed and the cap begins to function again.
I would say that poor caps have been used in the build for this to happen over such a relatively short period.
Cheers,
DV
I would say that poor caps have been used in the build for this to happen over such a relatively short period.
Cheers,
DV
boggit
New Member
As above I have been in touch and will resolve the issue next week. I guess we are all human and we backed each other into a corner, a corner from which I apologize.
I would say its only affected a small % of early amps. The above amp was nearly 3 years old and the 72 we produced.
Another aspect is the closest commercial product using NC500 SMPS700A1200 from a mainstream manufacture the Bel Canto REF600M $4995 our amp using
over $400 of discrete components in the buffer is $2300 and offers performance way beyond its price.
Our Warranty in now 2 years and I'm sure there are a few customers out there who can testify to our very quick responses and support which we take personally perhaps a little to personally
a lesson learned and again we apologize to all involved.
I would say its only affected a small % of early amps. The above amp was nearly 3 years old and the 72 we produced.
Another aspect is the closest commercial product using NC500 SMPS700A1200 from a mainstream manufacture the Bel Canto REF600M $4995 our amp using
over $400 of discrete components in the buffer is $2300 and offers performance way beyond its price.
Our Warranty in now 2 years and I'm sure there are a few customers out there who can testify to our very quick responses and support which we take personally perhaps a little to personally
a lesson learned and again we apologize to all involved.