[jymy]

Hello,

So i bought my first D-class recevier ever and couldnt be happier with the sound. Nuprime really deliver good clean and strong sound from my Revel M105 speakers

Then comes the But,

But noticed yesterday when listening to music that the right speaker made a scratching noise at some frequensies. The sound comes and goes and doesnt really happen all the time. So started to test what may cause the noise. Tried shifting cables, shifted left to right speaker, tested several inputs and sources, and the scratching sound always comes from the right channel, and it only appears when i play at higher volym than 35 and if i increase or decrease the volym rapidly, with the volymknob or from the remote, the scratching sound appears. Really annoying because the sound otherwise is very satisfying.

Any one have any idea what could be wrong?

PS: I am from sweden so sorry in advance for my english

[Evoke]

Hello,

So i bought my first D-class recevier ever and couldnt be happier with the sound. Nuprime really deliver good clean and strong sound from my Revel M105 speakers

Then comes the But,

But noticed yesterday when listening to music that the right speaker made a scratching noise at some frequensies. The sound comes and goes and doesnt really happen all the time. So started to test what may cause the noise. Tried shifting cables, shifted left to right speaker, tested several inputs and sources, and the scratching sound always comes from the right channel, and it only appears when i play at higher volym than 35 and if i increase or decrease the volym rapidly, with the volymknob or from the remote, the scratching sound appears. Really annoying because the sound otherwise is very satisfying.

Any one have any idea what could be wrong?

PS: I am from sweden so sorry in advance for my english

Switch the speaker leads - it sounds like you have a damaged voice coil. By switching them, if you still hear the sound, that should confirm that. Also, listen closely, if the scratching sound only comes from the woofer, mid or tweeter, that would indicate a damaged driver.

[jymy]

Thank you for the suggestion, but i have tried that and the scratching sound does not follow the speaker, or the cables. The sound always comes from the right channel so i assume that speakers and cables are ok. I even tried the speakers with another recevier today and they sound clean.

[jymy]

Bit of a correction after i listened a bit more thorough. Scratching is maby the wrong word to describe the sound, its more of a crackling/popping sound, and it definitely comes from the right channel. Sometimes i can here it directly after i start the receiver without any music playing and it doesnt get louder even if i play at higher volyms, thats why i haven´t heard it earlier.

Any more suggestions?

Thanks!!

[rustydoglim]

As you mentioned, the low volume noise comes and go from time to time.  This doesn't look like any component failure, but some sort of interference.
Take note of how often it happens. Connect the power cable to a different wall socket.

[Samoyed]

Op, send me a pm and I’ll tell you my experience.

[jymy]

Thank you for the suggestions.

I have now tried another wallsocket but the problem with the right channel remains, but when i connected the HD-AVA to a another amplifier and just used the dac and preamp section of the AVA, all the scratching noises was gone, just pure clean music. So it seems that the right amp module maby is the culprit? Contacted the swedish distributor and they also suspected the same thing and to change the part wasn´t so expensive, about 3000 sek ( 300USD).

I suspect that i dont have any warranty left on the machine but is there a way to see how old it is?
Thanks in advance!

Regards Simon

[rustydoglim]

Contact helpdesk.nuoem.com and the amp module should be replaceable. I assume that you have swap the outputs and the noise went to the left side.

[jymy]

thank you, will try to do that  yes when swaping the speaker outputs in back the scratching noise went to the left side, no matter the configuration the noise always came from the right side amp module.

[jymy]

Well, i found the problem with the amp.

Decided yesterday to open it up to look if i could find anything loose or broken because the noise to me sounded like bad ground, like when you are talking to a microphone and when the cabel has poor connection it makes a scratching noise, and found one cable going to the right side amp(i believe) to have come up from the contact and the black cable(ground?) was barely on. Cleaned the contact and pushed it in and tried again, the noise was gone And maby its a placebo but i think everything sounded even smoother and nicer now.

Feel i little stupid that i didn´t do this sooner and before engaging so many others to this case 

I bought the HD-AVA second hand and i must have gotten a harsh ride and thats why the cable got loose.

Thanks for all your help!!

/Really happy Nuprime owner!!

[rustydoglim]

Thanks for your DIY support.