[AllanS]

Lots of hours on it now.  I have to say that increased dynamic range was immediately noticeable and a nice improvement.  I have bass foundation, so haven't assessed any change there.  Highs are taking getting used to.  My guess is that they are now more in line with other amps in the lineup and were somewhat mellower in the original AMG STA. 

Michael will be over Thursday with his Evo STA, so I will have an excellent opportunity to compare directly.

Thanks for your initial impressions.  The Evo STA comparison will be particularly interesting.

[muellec3]

Another EVO STA owner here very interested in the comparison impressions. Looking forward to hearing from you.

[rustydoglim]

Despite the similar model name (STA stands for stereo amp, not the design), AMG STA-SE and Evolution STA have different technologies.

Evolution STA has the "ODC" design for distortion cancellation based on feedback as well as device characteristic, so with a highly resolved speaker, it is able to provide more details than AMG STA-SE.
AMG STA-SE on the other hand, incorporates a design that reduce PWM and DC voltages noises, among other improvements.

I think for mid range speakers, the performance of AMG STA-SE and Evolution STA would be very close. Evolution STA will show its advantages with high end speakers.

[pstrisik]

Michael and I had a good visit.  Many thanks to him for bringing his EVO STA.  We setup the EVO STA and the AMG STA-SE side by side (I should have taken a photo  ). 

The system is:  AURALiC VEGA G2/LEO GX => amp via RCA => Omega Super Alnico Monitors - High Output (SAM-HO).  I also have powered mid-woofers and powered subwoofer, but we listened with and without those.

I don't think the SAM-HO's are the best match for NuPrime amps.  They are full range with no tweeters and typically do best with lower wattage class A amps.  Nevertheless, here are my impressions.

The EVO was more refined with a smoother top end while the AMG was more energetic and a top end that is now more forward (compared to the non SE).  I found the EVO to be more relaxed and polite with that "ease" of presentation.  The AMG however, got my foot moving with the music.  It was a fuller and warmer sounding.  The EVO was more transparent with a tad bit more defined soundstage/imaging.

Overall, money aside, if I had to pick one to live with, it would be the AMG - surprisingly. I'm betting though, with more conventional speakers, I would opt for the EVO.

This was in my main system as described.  My amp that usually lives in that system is a 1970's Pioneer M-22.  Class A, 30wpc.  A better match for the Omegas.

After Michael left, I moved the AMG STA-SE back to my office system where I had been using it before upgrading to the SE.  That modest system is:  AURALiC ARIES Mini => amp => KEF Q1 bookshelf speakers.  The AMG likes it there.  These little bookshelf speakers have can have impressive bass for their size in a smaller room with the right amp - down to 45Hz +/- 3db.  The AMG STA-SE seems to be the right amp!  Here the music is natural sounding with full frequency range and really good dynamics.

So, FWIW, there you have it!  Thanks again Michael.

....Pete

[AllanS]

The AMG however, got my foot moving with the music.  It was a fuller and warmer sounding. 

Many thanks to you and Michael for putting the two together in the same room.  This comment really nailed it for me though.  Much as I’d like to have both, the amp that is most engaging is the one I’ll plug in 90% of the time.

[Skyscratch]

Hello,

Probably the first french owner of an AMG with a kit upgrade gracefull french Distributor of Nuprime.
I am so surprised, sound is very clean, background are silent and dynamics are just !
My Klipsch Heresy IV show theirs limits but my Wife Said «you will be happy, it’ s very good for now », best value indicator !

Thanks a lot Jason and all Nuprime’s team, normal people like me could approch the clouds of Hi-fi …

Ps: a professionnal ( DAC builder )  have made the job and it seems remove solders is not so easy

[mresseguie]

Michael and I had a good visit.  Many thanks to him for bringing his EVO STA.  We setup the EVO STA and the AMG STA-SE side by side (I should have taken a photo  ). 

The system is:  AURALiC VEGA G2/LEO GX => amp via RCA => Omega Super Alnico Monitors - High Output (SAM-HO).  I also have powered mid-woofers and powered subwoofer, but we listened with and without those.

I don't think the SAM-HO's are the best match for NuPrime amps.  They are full range with no tweeters and typically do best with lower wattage class A amps.  Nevertheless, here are my impressions.

The EVO was more refined with a smoother top end while the AMG was more energetic and a top end that is now more forward (compared to the non SE).  I found the EVO to be more relaxed and polite with that "ease" of presentation.  The AMG however, got my foot moving with the music.  It was a fuller and warmer sounding.  The EVO was more transparent with a tad bit more defined soundstage/imaging.

Overall, money aside, if I had to pick one to live with, it would be the AMG - surprisingly. I'm betting though, with more conventional speakers, I would opt for the EVO.

This was in my main system as described.  My amp that usually lives in that system is a 1970's Pioneer M-22.  Class A, 30wpc.  A better match for the Omegas.

After Michael left, I moved the AMG STA-SE back to my office system where I had been using it before upgrading to the SE.  That modest system is:  AURALiC ARIES Mini => amp => KEF Q1 bookshelf speakers.  The AMG likes it there.  These little bookshelf speakers have can have impressive bass for their size in a smaller room with the right amp - down to 45Hz +/- 3db.  The AMG STA-SE seems to be the right amp!  Here the music is natural sounding with full frequency range and really good dynamics.

So, FWIW, there you have it!  Thanks again Michael.

....Pete

Thanks for posting your impressions, Pete! 

I've been a bit busy since that day <I'm a granddaddy now! >, so I'm only just now getting around to replying.

It's always interesting to me to read or listen to people's impressions compared to my own impressions. We all hear things differently. I generally agree with your assessment, but with some differences. You said, "The EVO was more refined with a smoother top end while the AMG was more energetic and a top end that is now more forward (compared to the non SE).  I found the EVO to be more relaxed and polite with that "ease" of presentation.  The AMG however, got my foot moving with the music.  It was a fuller and warmer sounding.  The EVO was more transparent with a tad bit more defined soundstage/imaging."

I, too, felt the EVO STA was more refined sounding with a smoother top end while the AMG had a livelier more forward sound. I agree that the EVO is more relaxed and polite. However, my feet didn't get a-tappin' with either amp. This could have been because of the speakers or <more likely> due to how tired and unrelaxed I was thanks to that day's hectic schedule and hundreds of miles of driving. I wish I had had more time to listen to more tracks, and that I had been more relaxed, but I'm very glad for the listening opportunity. Based on the short comparison <and previously mentioned hectic schedule>, I preferred my EVO STA sound over the AMG sound - but I may be biased. 

I continue to be very impressed with Nuprime products both for sound quality and reasonable pricing.

Thank you so much for the chance to listen to your speakers and to compare our two amps! 

Michael

[pstrisik]

You are very welcome!  And will be again if you find your way up here more.

Also, my speakers were not your cup of tea, as well as not the best match for the NuPrimes. 

But, we each like our own amp the best.  Great outcome! And, as Dana Carvey would say, "How conveeenient!"

[AllanS]

I've been a bit busy since that day <I'm a granddaddy now! >, so I'm only just now getting around to replying.

Congrats to you and the family gramps!  Thanks much for putting in the long day and offering your impressions.

[rustydoglim]

HiFi Advice will have a detailed review of AMG STA-SE out in the next few days.
Christiaan Punter has reviewed many of our amps and he is always spot on with his comments.
Our goal with all our amps is to deliver exceptional value within their respective price ranges.
Christiaan uses the CH A1.5 as his reference amp, and with each new model, we’re getting closer to surpassing the CH A1.5 at a fraction of the price. The Evolution STA was reviewed as comparable to the CH A1.5, with some sound characteristics being better and others slightly less.

We are relentless in our pursuit of the flawless amp.  It is a near impossible goal like Fusion reactor
But eventually we will get there. The race is on to see if we achieve a near flawless amp before a working Fusion reactor.

[rustydoglim]

https://www.hifi-advice.com/blog/amplifier-reviews/power-amplifier-reviews/nuprime-agm-sta-se-stereo-power-amplifier/


Notable statements from the review:

As mentioned in the original AMG STA review, it addressed all of the ST-10’s weaker areas while raising the overall quality to such an extent that it comfortably positioned itself among high-end competitors that cost multiples. But in the process, it also gave up a good portion of the ST-10’s bass heft and overall robustness. As a result, we had two amplifiers by the same brand on opposing ends: the exceptionally robust, full-bodied ST-10 and the exceptionally agile, airy, and refined AMG STA.

The first question on my mind was: Could the new model hold the ideal mid-position? Well, upon first powering up the new amp, that question was immediately answered.

…….

The AMG STA-SE does not fall into this trap and walks the fine line between maintaining control and stability on the one hand and providing emotional involvement on the other. This is one of NuPrime’s most alluring qualities: their Class-D products do not sound like other Class-D products.

……

The AMG STA-SE is a different animal. Given its ballsy and confident yet liquid presentation, it’s perhaps more like Class A than Class A/B. More specifically, no longer Jeff Rowland-esque, in some ways, it now sounds more like a Pass Labs amplifier.

…….

The AMG STA-SE’s timbre has truly improved beyond the original model and is now indeed much closer to that of the ST-10. But it’s not quite as neutrally natural or well-balanced as the CH. In terms of articulation, control, transient behavior, and dynamics, I have to admit the little NuPrime more or less performs at a similar level. Remarkably for a big power amp, though, the CH also has airier treble, sounds lusher (more free-breathing), is more fluid, and has more delicacy. Compared to the Big Swiss, the newcomer still sounds less convincingly realistic. But to put this into perspective, the AMG STA-SE sounds more natural than all other Class D amplifiers I have heard.

So, the reference-class amplifier still wins, but not by as big a margin as the price difference might suggest. Ultimately, I don’t expect a 2.500 euro amp to perform as well as a 30.000 euro amp, let alone beat it.

………

With the AMG STA-SE, NuPrime has successfully combined the characteristics of two of their different product lines. It has the full-blooded tonality, body, and robustness of the ST-10 and Evolution STA, as well as the fluidity, refinement, and flow of the original AMG STA. Uniquely, for a Class-D design, it delivers control and musicality in equal measure.

The AMG STA-SE may no longer be the absolute bargain it was in 2020, but I still do not know any other amplifier under 5000 euros that equals it, let alone one that comes close at the same price point.

[madinaudio]

Hello
For use as a mono block, can each block be used in XLR (and which one?).
Regards

[AllanS]

I believe if you look at the back you will find the XLR or single ended mono connection identified by the red line.  In a similar way the correct speaker binding posts are identified.

[madinaudio]

Hi
I find  what is clearly mentioned by the red line is the HP connection and the RCA connection! On the other hand there is a doubt about the XLR connection.The red line does not show the XLR. Nuprime could give me more details. Or if anyone has had to do it with a AMG STA or a AMG STA SE

[pstrisik]

NuPrime neglected to put this information in the manual for the AMG STA.  Here it is for the STA 9x, which has the same layout.  It is obvious to me that it is the right XLR input, just as it is the right RCA input.  The red line includes those two and excludes the L XLR.

[rustydoglim]

Sorry, the connection was missing from the AMG STA-SE manual.  I have asked support staff to update the manual but he has been too busy and keeps forgetting.  The STA-9X manual shows the same configuration for AMG STA-SE.
The XLR connector can be used for mono configuration.

[Skyscratch]

I’m back because of my pleasure ! 
2 weeks burn in and it’ s better than i expected ! Really, Bass are deeper but very fast, voices are justs very good… All types of music i like, Antonio Forcione, Kessoncoda, Melody Gardot, In Flames ( not a joke ).
Soundstage explose in dimension with air !
The AMG STA wants to show me so much things i have never understood with some tracks …
Again, i am m very gratefull to Nuprime ( i don’t earn anything, i will finish to paid upgrade with Christmas period ) …

One of my collegue ( musician before everything ) go at home few days ago, he has listened track 2 of Trio Chemirani Invite and he said « They are just in front of me , Thanks » …

[rustydoglim]

Thanks! Please share your feedback about Nuprime on social media, especially in various Facebook audiophile groups.