[sresener]

Hey everyone I thought I would reach out to the community for some help.

One of my amps all of a sudden developed a very loud hum in the speaker.  The hum is the same with or without any source connected.

Nuprime advised me to open the amp up and remove the ground wire that connects the cooling radiator to the amp board. I did this and the hum disappeared.

I was also advised to remove the top half of the cooling radiator as it was over engineered and not needed. (I did this also).

The problem is the second I put the cover on a very very slight hum comes back.

Nuprime advised me to take the top cover off my other amp and try it on the effected amp and the slight hum was still there.

But I would like to know after a year how a loud hum (can clearly hear from 40 ft away) would just show up. And what would be the best way to fix this.

Thanks in advance for any help.

[djbnh]

Hey everyone I thought I would reach out to the community for some help.

One of my amps all of a sudden developed a very loud hum in the speaker.  The hum is the same with or without any source connected.

Nuprime advised me to open the amp up and remove the ground wire that connects the cooling radiator to the amp board. I did this and the hum disappeared.

I was also advised to remove the top half of the cooling radiator as it was over engineered and not needed. (I did this also).

The problem is the second I put the cover on a very very slight hum comes back.

Nuprime advised me to take the top cover off my other amp and try it on the effected amp and the slight hum was still there.

But I would like to know after a year how a loud hum (can clearly hear from 40 ft away) would just show up. And what would be the best way to fix this.

Thanks in advance for any help.

I do not have an answer re: "I would like to know after a year how a loud hum (can clearly hear from 40 ft away) would just show up." Regarding "what would be the best way to fix this" is dependent on warranty status, etc. The following company, "TDSS (also Ozark Mountain Audio, same people)", is "the factory authorized RMA - Warranty Service & Technical Support provider for NuPrime products being distributed in the USA and Canada." Might want to go to their page (think it refers you to Summit Hi-fi)/ view their info / reach out to them about the issue.

Sorry to read about your unit's issue, and wishing you the best possible resolution.

[Samoyed]

You have every right to be unsettled over this, especially given the price of the amp. All I can do is offer my sympathy. While I enjoy my evolution DAC and cd transporter, I’ll never buy another Nuprime product given the way it dealt with an analogous issue I had with popping.

[sresener]

I was just hoping someone would have some good ideas, I'll keep working with nuprime on this, as tdss never got back to me and summit hifi went silent 😞

[sresener]

https://m.youtube.com/watch?v=d4SVDl_04HU&t=6s

[JackD]

Unless somethings changed Summitt HiFi is John Casler.  Try PM.

[sresener]

I contacted the Canadian distributor in the middle of January,  I have a ticket with nuprime ect ect ect. I'm polite and patient,  im just at the point where I need my amp fixed properly or I have to throw them away and get another

[Bob Stark]

I sent you a PM

[840wolf]

Mine did also. going on 2 years now. If the Amps got shut off, and turned back on, one would buzz very loudly through the speaker. Banging( not a very heavy banging)  on top of the amp in different places until I found the spot that would silence it, and not always the same spot on the amp would kill the buzz. As long as i didn't turn it off, the buzz would stay away.

[sresener]

The only way I can make the hum dissappear is disconnect the ground wire from the heatsink to amp board and keep the top cover off. The hum showed up mid song at a low volume. The hum is barely audible when I do put the lid on with the ground and heatsink top removed.

But I have 50.00 amps with no ground hums.......

[sresener]

A funny story.

I bought the mytek manahatten II that Bill used in his review of the evolution amplifiers at sonicunity.com

The dac would randomly lock up. Shortly after I received it, we'll it locked up completely.

I reached out to mytek and a time was arranged where Damien from mytek called me to try and force a firmware update. The attempt didn't work.

So a ticket was made I shipped it to them and they had to replace the whole board, they then shipped it back. The only cost I occurred was shipping to them.

On top of that Bill ( the seller) was wonderful.

The whole process took 5 weeks and the dac has worked perfect since.

[Dint]

Hi sresener

Has your issue been resolved?

[sresener]

Yes last week the amp board was replaced. Everything is back to normal.

[Samoyed]

How did you get it replaced?  Did you send it somewhere?

[rustydoglim]

If I remember correctly, he said he can replace the board so we shipped him a replacement board (free of charge).

[sresener]

Yes Jason is right. I have a lot of experience with repairing electronics and It was a easy swap for me.

[Puk]

You wrote: Nuprime advised me to open the amp up and remove the ground wire that connects the cooling radiator to the amp board. I did this and the hum disappeared.
My question: how do you open up the amp?

[rustydoglim]

Hold the feet with your fingers and unscrew it to expose the screw holding the bottom plate. And then remove more screws....
You shouldn't open it unless instructed by support staff.

[Puk]

Thanks for the answer, I hear you concerning taking off the top cover. It's just that I have exactly the same problem with both my Evo's for a couple of months now after working fine in thebeginning; also when I touched the top cover or ls-cables the hum diminished. So I tried swapping everything there is to swap (cables, chords, different group panelboard, etc.). I brought them both three times to two different repairshops, twice of which to the official service repairhandler of NuPrime here. They couldn't find anything wrong; it just worked fine over there. Just after they came back from the repairshop they worked fine here too but after a while the hum came back and I couldn't get rid of it. The Evo's are only about two years of age but I bought them secondhand so there's no official guarantee anymore. Reading the story of sresener gave me hope that there is a "simple" fix by replacing the "amp board". Or are there also other known causes for the hum?

[rustydoglim]

What you are hearing is not electronics noise but the 50hz linear transformer hum. The transformer is very heavy and if it has been shipped or dropped several times it is possible that it is not as tight as new.  You can open the cover to tighten the screw on top of the transformer.