Review sample provided by Dimex
Retail Price: 4.995 euro
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With the Evolution STA, NuPrime presents an amplifier that delivers a breakthrough in distortion reduction. To achieve this, they employ a technique they call Only Distortion Cancellation (ODC). A typical feedback error correction design inverts the output signal for summation with the original input signal to derive the negative error signal, which adds to the next cycle of the input signal to form a more accurate output signal. NuPrime’s ODC Class-D design derives the error signal from MOSFET devices and the output filter circuit directly, significantly reducing the negative feedback signal, which resulted in a substantial reduction in distortion THD+N of 0.002% @1kHz(5W), and less than 0.005% THD+N at 1KHZ (2W-100W).
Highlights include a 650KHz high-speed switching frequency to allow greater resolution, the application of the high-end NJR MUSES8820 op-amp for the preamp stage, and the Class-D oscillation circuit, a 550W high-power, ultra-thin toroidal transformer power supply with a total of 52,000uF filter capacitors. The amplifier uses low resistance terminals and is able to supply a rated RMS power of 230W at 8 Ohm and 40A of current.
After having favorably reviewed the ST-10 and the AMG-STA and having concluded that they have mutually exclusive strong areas, Jason Lim of NuPrime later mentioned that they were working on a new amplifier that would combine the strong points of both amplifiers. That new amplifier is the Evolution STA. Imagine my anticipation!
Review Context
For this review, I will use my main system, consisting in the basis of the CH C1 DAC, CH L1 preamp, CH A1.5 power amp, and Magico S1 MkII speakers with the Grimm MU-1 Music Server.
My power installation consists of a Siemens Sitor Cylindric Fuse, feeding an uninterrupted run of solid-core installation wire that ends in three wall-mounted GigaWatt G-044 Schuko Wall Sockets. These wall sockets feed three Popp/Eurolite unfiltered aluminum 8-output distributors via insulated runs of the same kind of solid-core installation wire.
Prior to starting my serious listening sessions, I made sure to leave the amp powered on for several days, and even before this, the importer also used it at home for two weeks meaning that the unit should be properly run in.
Listening
For my first listening, the Evolution STA was positioned on top of the CH A1.5, connected with the stock power cable, just like the A1.5, as the only exception in my system. While this will probably not be ideal for the amplifier, it does provide the ideal setup to compare the two amplifiers. Is there any sense in comparing the NuPrime to an amp costing over four times as much? Maybe not for prospective buyers, but for me, it is. The CH remains my reference and as such, it is a logical starting point for me. Don’t worry, though, as I will also compare the Evolution STA to the very affordable NuPrime AMG-STA and ST-10.
After having listened to a varied playlist via my regular setup, I reconnected the AudioQuest Fire RCA interlinks and the Jorma Trinity speaker cables from the CH A1.5 to the Evolution STA and adjusted the CH L1 preamp -3dB to compensate for the NuPrime’s higher gain. Even though I have not forgotten how great the AMG-STA and the ST-10 are relative to their price point, still, I prepared for the sound quality to take a few steps back with the Evolution STA compared to the CH. But that’s not exactly how it went down. Rather, my first impression was one of amazement.
The Evolution STA sounds marvelously energetic, expressive, and utterly coherent with immense neutrality but without tipping over into leanness or coolness. The amp is also very linear and quite detailed but not revealing to the point of being analytical, let alone clinical. First and foremost, it paints the complete musical picture while sounding nothing like your typical Class-D amplifier.
Between the CH and the NuPrime, certain key aspects have certainly noticeably shifted, but on the surface of it, and in an absolute sense, there is not very much to indicate that we just switched from a 31 K amplifier to one costing only 5 K. Honestly, it was more like switching from one high-end amplifier to another, invoking differences catering more to taste than to absolute quality. For instance, the Big Swiss amp remains the King of resolution and refinement. But to offset this, the NuPrime actually overshadows the CH in a couple of areas. Do read on to find out precisely how the two compare!
Nice review Christiaan! And also a thank you for following up on my suggestion to put two AMG-STA’s in dual mode to the test.
One little remark: on page 2 somewhere in the middle you mention AMG-STA which should be Evolution STA I assume.
Sooner or later, I will compare the AMG-STAs against the EVO STA and see if it is worth the extra investment..
Thanks Vincent! I double-checked but I don’t see an error. I presume you mean the following section? “but I feel that the AMG-STA also sounds airier and more refined and certainly more fluid”. This is correct:-)
Ah ok! I meant that section indeed. Then the AMG comparison came a little out of the blue for me, but if this was on purpose then all is good
It harks back to the introduction where I mentioned that the intention was to include elements of the ST-10 and the AMG-STA in the new Evolution STA amplifier:-)
After re-reading it, it is clear what you intend to say. My bad. Cheers!
No probs, Vincent, I appreciate the diligence and it’s always good to get feedback, especially since I am certainly not fool-proof!
Hello my friend.
I have recently been so lucky with Shunyata Power cords and interconnect cables and I need one more interconnect cable from Dac to pre or from pre to Power amplifier depends on where it sounds best with my Shunyata Delta V2. I hope to see a review of Shunyata against Driade.
Thank you, can also send mee those CH Precision Gear when you fel bordet about them.
hi Christiaan,
Do you think the Audio-Gd HE-1 preamp and the NuPrime Evolution STA will be a good sounding combination ?
Best regards
I have not heard the Audio-Gd HE-1, but based on my experience with the Master-1, I would think that it would indeed pair very well with the Evolution STA.
Hi Ben, did you already experience the Evo STA combined with the Audio-GD HE1 and if so: was it the tube or transistor version?
Hi Christiaan,
Any following feedback on the comparaison with dual mono AMG STA vs Evo STA ?
Only that a pair of AMG STA amplifiers does not make an EVO STA. They remain very different, each with its respective strong suits. While 2 AMG STA’s sound better than a single unit, they still excel in fluidity, refinement, nimbleness, and air while the EVO STA excels in robustness, body, impact, and tonal saturation.
Thank you Christiaan.
Depending as well on the speakers. What could be your favorite option between the two with Martin Logan EL 11 ?
The articulation with the active woofer is sensitive
It totally depends on what you are personally after. If you want to Rock and roll and a live-concert-like “outgoing” sound, then the ST-10 or EVO STA is your best choice. The ST10 is even a little bit more of a party animal but less refined than the EVO STA. Do you want audiophile refinement, fluidity, air, and flow, then AMG STA is your best choice. Personally, I lean toward the AMG. ESL11A has very good bass control but like all Logans, it is a little lean in the upper bass, where the cabinet meets the foil so to say. Not all listeners are bothered by this though. If you find that you are, and you find this aspect more important than some others, then the ST-10 and EVO STA are probably the better options for you.
dear Christiaan,
Reading your comments the more I’m convinced that combining my Audio-Gd HE-1 preamp, the big brother to the Master 1 you have tested, with the NuPrime AMG STA power amp in mono mode will give the best sounding result I’m after with my open baffle speakers. The latter are dipoles speakers that you have used extensively in the past. My OB’s use 4x 10” woofers per side so that’s why I’m thinking the mono ‘d version of the AMG have the power to control the speakers well.
I listen to a lot of classical music and the refinement and fluidity you say these amps are capable of will suit this genre of music even more than the Evolution STA. Is that your opinion as well ?
Best regards
Hi Ben, indeed for classical, I would prefer the AMG-STA, either a single amp or the bi-wired pair. The AMG is never lacking control, not even with Magico Q5s which are really hard to drive. I don’t know how your woofers are connected and how low the combined impedance is, but I suspect that even a single AMG-STA may surprise you. If desired, you can always add a second unit.
Its all a matter of mixing and matching. I have good hopes for the Grimm Audio MU1, HoloAudio Spring 3 DAC, EVO STA combination (Jorma digital and Driade analog interlinks) together with my Magico A1s. EVO STA to arrive soon. Let’s see if the EVO STA can beat the AMG STA dual mono config
Hi Christian,
Taking the above setup in account, which reasonable priced (below 10k) preamp would fit best in your opinion?
Hi Vincent, to which setup are you referring? If you are asking for an ideal affordable preamp for the EVO-STA then I would say the AGD Master 1. However, I have not heard the higher-end AGD’s, nor NuPrime’s preamps other than the AMG-PRA. There seems to be a big gap between affordable preamps and the high-end with precious little in between. The next best preamp, price-wise, that I would recommend is the Aries Cerat Incito-S which will make a stellar sonic match but at ~14.000 euros it’s well obove your price point. Maybe the regular Incito (non-S) might be an ideal candicate.
Thanks for your answer. Yes I refer to the NuPrime EVO STA. Different affordable preamps that might match are perhaps
– Pass Labs XP12
– Mark Levinson 326s (2nd hand available for 4k)
– HoloAudio Serene
I talked to Marco (Hexagon) and he offered to try the COS D10 preamp
Hopefully there will be a match
Hi Vincent, A 326S second-hand might be quite nice although I never had much success with my 320S. If going second-hand, I think I would prefer a Jeff Rowland preamp such as the Synergy 2i. The Pass is not quite as fluid, airy, or refined as I would like and given the EVO STA’s character, I don’t think that would result in an ideal match. Holo is on the list to review (no timetable yet). The COD D10 slipped my mind because I see it as a DAC primarily with a preamp on board but its preamp section is actually excellent. Do let us know how you get on with the D10!
On my short list are:
– COS D10
– Audio-GD HE-1 Mk2
– Holo Audio Serene KTE
Will let you know the outcome.
Thanks for your hifi-advice
Short update: I got the chance from Schelto to try the Kora TB200 and got blown away. My search for a pre/power amp combo is over… although the Audio-GD HE1 Mk2 wasn’t bad at all
I have not heard the TB200 but the Kora TB140 has also surprised me. Almost the polar opposite in sonic presentation from the NuPrime AMG STA but a great amp indeed.
Curious if you have had an opportunity to compare the NuPrime to the Bel Canto REF600M?
Alas, I have not heard the Bel Canto.
Thanks for your advice
Good morning Christiaan.I have a question,would the nuprime evolution sta match well with the Totem Tribe Towers.If not which amp would you recommend to me.No i have an Arcam avr 850.Thanks in advance.
I have never tried any Totem speakers in my system so can’t really comment. My gut feeling is that they are nice and lively and direct and the combination with the EVO STA would likely result in a more solid, direct, and robust sound than the Arcam. But this is pure guesstimation on my part…
Now that the Evolution Two has arrived.. time for a review of the new kid on the block?
This was indeed discussed but so far no plans have been made just yet.
2 years after my purchase, I still enjoy very much my STA dual mono amps with ML 11a. A lot of times I surprise myself how good the sound is, so close to really.
This only short come I feel sometimes is the lower impact / softness on rocks but nothing terrible vs all great advantages.
Great to hear Phil! After owning the AMG STA in dual mono setup I switched to the Evolution STA. Little more dark but also more authority in general. Though the little AMG’s were more ‘fun’. I still thinking of purchasing them again fir my second setup. What preamp are you using?
They are directly connected to a DAC Totaldac D1 Core with volume control through KLR cables. The balanced vs imbalanced switch has a lot of impact on the restitution, much better with balanced position.