[Spacewatch1904]

Dear Forum,
I've been following the good discussions here silently for quite a while but want to become more active onwards. I've been using a Nuforce P20 preamp for some years which I've recently complemented with two NuPrime Evo-Two mono blocks. This combo sounds absolutely gorgeous to me as it combines details, prat, speed, soundstage and musicality in one setup, which I've rarely heard elsewhere. I use them with Avantgarde horn speakers which don't need all the power available but sound terrific anyway. I'm also thinking of using a NuPrime DAC in the near future to replace my current PSAudio DAC.

The amp combo looks like sculptures and a piece of art which is great on the eye but gives me a little bit of a headache at the moment. There is a buzz on one of the Evo-Two amps since moving the device around some days ago and I would like to have a look inside for a potential initial diagnosis. Although I am good with electronics, I seem to come to my limits understanding the beautiful casework of the amps. I simply don't manage to open the top plate for an inside inspection. I have loosened the four (main?) screws of the backplate near the edges which I thought are key to removing the top plate. But removing the four screws doesen't see to release the top plate or anything else. I don't want to test with more force whether I can make it move in the absence of a deeper understanding how the entire case works. I don't want to disassemble the whole thing, I just want to remove the top plate and I wonder where I'm failing to understand how the case works.

Could anybody who has opened an Evo-Two amp before or a Nuforce/Nuprime product with the same principal casework design please enlighten me how I can accomplish the task of removing the top plate?

That would be marvelous and I thank you already in advance for sharing your knowledge with me

Warm regards
Christian from Frankfurt Germany

[rustydoglim]

There is a buzz on one of the Evo-Two amps since moving the device around some days ago

Are you hearing the buzz from the speaker or the amp's transformer?  This is either grounding related or something become loose (ie transformer).

Please wait for instruction. Normally you remove the 4 bottom feet (use your hand friction) to expose 4 screws under the feet. After removing the bottom plate, more screws are exposed. The top cover is connected and secure of screws from the bottom.

Don't do it until we upload the instruction.

By the way, thanks.  Evolution Two is our best amp.

[Spacewatch1904]

Dear Rustydoglim,

Thanks so much for approving my membership and the kind support offered. The buzz is internal from the unit, so maybe something came loose when moving it around.

With your kind help, I can at least have a look inside to check. Based on your initial feedback at least I'm not too disappointed about myself that I didn't manage to figured out the opening procedure alone

Thanks again and looking forward to some further instructions.

Best wishes
Christian

[rustydoglim]

From your description, I am quite certain it is from the big transformer that became loose.  Transformer has natural frequency of 50Hz (Europe AC).  Even though it is tighten and glued during shipping, if it is bumped around (even if there is no sign of damage on the packaging box) the inertial force could loosen just a little for it to hum in its natural frequency. There is a big screw at the top of the transformer where you can tighten it.  Even if you don't, the sound won't affect the speaker.

[Spacewatch1904]

Dear Rustydoglim,
Thank you for the photo, which makes it easy to locate the potential source of the hum. Equipped with the first info on entering the case from the bottom side and the transformer picture, I feel that I'm now equipped to carefully approach this. I will report here about the results.

Thanks again for this marvellous support!!!

Cheers
Christian 

[rustydoglim]

You can use this Evo DAC document to open the top cover:
https://www.dropbox.com/scl/fi/2ih3n4h7k8vcw32njf7za/EVO-DAC-service-manual.pdf?rlkey=n6uonw4g7p5trmp653tnj4htc&st=l2cj7e15&dl=0

[Spacewatch1904]

Dear Jason,

Now that I've finally spotted that I am being supported by the great Mr. Jason Lim himself, I'm feeling double grateful and honored! Thank you Sir!

This pictured instruction is double helpful!

I will perform the "operation" over the weekend and will report back.

I am impressed that the owner of such a great company personally takes care of customers in such a nice and "humble" way. This is awesome

Thanks again and cheers
Christian

[rustydoglim]

OMG, I have been on this forum since August 1, 2005 
It is my responsibility to understand both the strengths and weaknesses of our products, no matter how minor they may be.
Some resellers might be wary of Nuprime using this forum in such an open and transparent manner (the community forum link is prominently listed on the website). I often told new customers to take a look at Nuprime/nuforce circle that goes back nearly 20 years. Usually our world class products have the best value for money but occasionally we had not-so-good products. If you are unhappy, tell us (by email) and we will make it up to you