Nord User Forum

[CelticSoulMan]

Hello gentlepeople,

Nord Grand, Silent in operation until two weeks ago, now an electrical fizzing from the OLED screen. I’ve a vast experience in broadcast tech, and the last time I heard high frequency voltage output oscillation from a screen was a phasing CRT.
Sound tech UK don’t wish to fix issues, it would seem, and the retailer (who is one of the good guys) has just posted a video of a shop floor model displaying same fault. Why do folks believe this to be normal behaviour for a failing component?
Cheers, look forward to the replies!

[pterm]

Welcome to the Forum!
Please note when you log in, the search function becomes available to help you find similar threads to your query.
This topic came up before:
https://www.norduserforum.com/nord-stage-forum-f3/oled-displays-nord-stage-3-t14909.html?hilit=oled%20noise
https://www.norduserforum.com/post124460.html?hilit=oled%20buzzing#p124460
OLED modules often contain a boosting power supply (either a charge pump or a DC-DC boost converter) to power the OLED panel. These boost supplies often generate audio-band noise from their components: Magnetic components like wire-wound inductors or piezoelectric components like ceramic capacitors either move or change shape with changing voltage. This makes them audio transducers.
Also, some DC-DC converters change their operating frequency or duty cycle to adapt to changing loads. This might explain why you didn't notice the noise at first.

In my opinion, this noise seems within normal expectations for an OLED powered from a single digital supply.
Normal does not however mean desirable: Nord's specialize in superb samples and intuitive user interfaces but their hardware design choices leave room for improvement...

I own an Electro 3HP, whose keyboard makes many interesting noises, but if instead I listen to the music it makes, I stop noticing the mechanical and electronic noises. Hopefully this occurs for you too.
-pterm

P.S. Please link to your retailer's video (cited in your post) if possible. Thanks!

[CelticSoulMan]

Thanks for the replies people, all very helpful. I guess I’ll fix it myself and just send the criticism to Nord. If they can’t get a screen to function and/or repair, then it’ll be last Nord I buy, sadly. £3000 to be treated like an idiot by Sound Tech isn’t something I wish to put up with.

[Mr_-G-]

Rather than fixing it yourself (what would that fix be BTW?) I would let Nord know and talk directly to the Service in the UK to understand what is the situation. I doubt it is whether "they wish" to do it or not. The service guys probably follow the guidelines from Nord (who are the ones that ultimately source the parts and pay for the service). I remember somebody posting here that buzzing transformers are "a non-serviceable issue" according to Nord. Maybe the buzzing OLEDs are of a similar nature (i.e. not ideal, but do not affect the function of the instrument and are not really "failing components" either).

[CelticSoulMan]

“unless the noise then produces a harmonic and an extremely high, annoying pitch to the ears”

This is what I’ve been saying. The longer the unit is on, the worse the it gets. The pitch is from behind the “3” button below the screen. I can’t see how this isn’t a fault, considering it was totally silent since new, and now not.
Ridiculous that Nord repair tech (with a past history of problematic repairs for different company) can simply overrule an issue I’ve raised to avoid servicing under warranty, and a retailer left to foot the cost of return, which ultimately is passed to me. The piano is three months old!

[fieldflower]

If it is loud enough to present an actual problem, then it is a fault.
If You can demonstrate it to the retailer they should take it seriously and make sure it's fixed.
Some OLED buzzing is to be expected, but if it's actually loud I'm sure Nord would also see it as a problem and exchange for an OLED that buzzes at normal levels.

[CelticSoulMan]

Thank you, Lew, and all.
I’ve recorded some audio and will link it when uploaded.
I was also thinking that frequency and ear age may play a factor in the “annoyance” of the high pitch and certainly the brick wall the piano is sitting in front of is reflecting frequencies back. Still, shouldn’t be that distracting.

[Schorsch]

I checked this with both of my NS3s, the OLED display buzz is there but nearly inaudible. I have to put my ear directly on the display to hear the buzz, it's a very high pitch "hizz" kind of noise. My dB meter does not measure it at all so it's more quiet than the surroind noise in a normal quiet room.

This is what I would consider as perfectly normal and is not disturbing in any way. If it's significantly louder and you can hear the buzz at normal playing distance to the keyboard or even when you are playing it should be fixed from my point of view

[CelticSoulMan]

Hey again.
A link to the transformer screen buzzing. It’s two frequencies, low and high.
No video on this as it’s recorded from player POV with a Zoom H4N on 120° stereo.

https://youtu.be/il6UC_ECN94

Cheers

[ajstan]

Hey again.
A link to the transformer screen buzzing. It’s two frequencies, low and high.
No video on this as it’s recorded from player POV with a Zoom H4N on 120° stereo.

https://youtu.be/il6UC_ECN94

Cheers

Sounds like an electric shaver and a vacuum cleaner running at the same time. How far away from the display is the camera? It would be helpful to get a reference of the noise floor in the room by powering off the unit at the end of the video (or having it off at the beginning and turning it on. Capturing video would help to show the position of the microphone relative to the unit.

In any case, there is virtually no noise from my NS3-HA88 and NS3C when they are powered on. I need to put my ear closer than a foot from the unit to hear a faint noise. I think my hearing is good up to about 13kHz, so if it's a higher frequency, I wont hear it.

Maybe an EE can weigh in on the possibility that voltage/power differences between the US and UK could be part of the issue.

EDIT: +1 on what Lew said.