NuPrime AMG-PRA with 2x AMG-STA power amplifier
Review samples provided by Dimex
Retail Prices:
AMG-PRA preamp: 1.595 euro
AMG-STA power amp: 1.595 euro
In the initial NuPrime AMG review, I have focused mainly on the AMG-STA power amplifier, with the AMG-HPA headphone amp-preamp thrown in as a bonus. For this second installment, I have been sent a second AMG-STA power amplifier so that I can use a pair in mono-mode. Additionally, I have been sent an AMG-PRA analog preamplifier to round off the NuPrime system.
To summarize what I wrote in the initial review, I felt that the AMG-HPA headphone amp-preamp and AMG-STA form a compact-sized, yet powerful, versatile, and well-thought-out pre-power combination. Both the preamp and the power amp offer great value for money along with several very nice touches that belie the expectations for their respective, and collective, price range.
System Context
In this add-on review, I will again assess the pre- and power amplifiers individually and as a system, but in a condensed form since all the details can be read in part one. When listened to individually, this will be in the context of either the Aqua Formula xHD DAC with V2 output board along with the Audio-GD Master 1 preamp, or the CH Precision C1 DAC. The source in both cases is the Antipodes K50 running Roon via network either to the C1 DAC or via HQPlayer to the Aqua LinQ, which is then connected via AQLink I2S cable to the Aqua DAC. The loudspeakers are the Magico S1 MkII’s.
AMG-PRA preamp
The AMG-PRA analog preamp offers much the same functionality as the AMG-HPA headphone amp-preamp but instead of the headphone section offers some refinements and a user-selectable 4-stage “Active Low Frequency and Harmonic Gain” control which is essentially a four-step loudness control.
Like the AMG-HPA headphone amp-preamp, the AMG-PRA builds on a big linear power supply and uses an ultra-wide bandwidth low noise JFET, single-ended Class A input design and a MUSES8920 Op-amp along with a MUSE S72320 Digital Volume Control. At only 1.595 euro (as opposed to 1.895 euro for the AMG-HPA headphone amp-preamp), the AMG-PRA offers even better value, if you don’t need the headphone output.
The volume knob works smoothly and precisely, its micro-pore led display provides a subtle but high-contrast reading that is legible even from my listening position at 6 meters. The supplied full-metal remote control with its polished metal roller-ball buttons puts the cheap plastic affairs of many competitors, even high-priced ones, to shame.
Top: AMG-HPAheadphone amp-preamp, bottom: AMG-PRA
The AMG-PRA preamp, when judged on its own, has a full and rich sound and threads a fine balance between sounding smooth and being revealing, offering great resolution without ever sounding lean or harsh. A typical expectation bias might be to expect little bass or a lean sound from a component as diminutive as the AMG-PRA but the inverse is true. This preamp sounds as beefy as the biggest specimens that I have heard.
While the preamp is commendably even-handed and sounds essentially linear it is not quite as transparent nor as articulate, as the AudioGD Master 1. Resolution really is not in question but compared to the Master 1, or the C1 DAC connected directly to a power amp, the music loses a bit of vitality and urgency when using the AMG-PRA. In a way, it is a price to pay for its smooth, rich and forgiving nature.
Of course, I should emphasize that I am absolutely spoilt. The level at which I am judging these components is so far beyond what might reasonably be expected given their modest price that it’s just unfair. The thing is that the AMG-STA power amplifier is simply fantastic and that made me compare it to components that cost multiples. As logic has it, I am doing the same with the preamp. But as I have found time and again, it’s just impossibly difficult for any manufacturer to make a preamp that is 100% transparent, even if cost is not a factor. It’s not without reason that I do not use an analog preamp even though I have been in the position to hear the best of the best.
All things considered, and to be fair, the AMG-PRA preamp is likely to be used in a system with speakers of comparable cost, where its smoothness will most likely actually be desirable. And, apart from the Audio-GD, which is at an advantage due to 100% Chinese operations, I must admit that I have not heard any other preamp close to the AMG-PRA’s price range that performs similarly well.
AMG-STA power amp
The AMG-STA stereo amplifier can be turned into a mono amplifier with the flick of a switch. In this mode, the right-channel input is used to feed both amplifier sides and the speaker wire plugs connect to the two plus/hot-terminals. When switched to mono operation, the amplifier’s output is raised from 2x 130 Watts at 8 Ohms to 300 Watts at 8 Ohms. Considering that I am already hugely impressed with the stereo model, how much more could doubling up bring? Well, a LOT, as it would turn out. But before I take the power amp to the max, I will start with the NuPrime combo, consisting of the AMG-PRA preamp and a single AMG-STA power amp in stereo mode.
In order to be able to use the Jorma Trinity loudspeaker cables, I made a pair of custom adapters using WBT connectors and ViaBlue bananas connected via short pieces of OCC solid core wire. This assembly was then swapped in its entirety between the three amplifiers.
Listening
The AMG-PRA + AMG-STA form a beautiful combo, not only visually, but also in terms of sonic synergy, the preamp’s robust and full sound perfectly complimenting the power amp’s slightly leaner balance. The combined result is a musically always engaging sound that is solid and full-bodied, smooth and refined yet highly detailed and transparent, with perfect pacing, and great dynamics. Honestly, at 3200 euro, I haven’t heard a better amplifier, either integrated or separates.
But as great as the combo is, I already mentioned that the power amplifier is the star of the show. On its own, it is capable of performing on a level that is well and truly beyond what might be expected from an amplifier at its price point. To be more precise: if the preamp already performs at a level that belies its price sticker, the power amp steals the show as it has the ability to perform on the level of amplifiers that typically cost multiples of its modest 1.595-Euro price. I am not kidding!
Double Mono
After doubling up the amplifiers (still with the C1 as a source), the sound level becomes 6dB louder. After compensating for this using the C1’s volume control, it is immediately evident that the performance is raised further across the board. When bridging an amplifier, often, you gain output voltage but not robustness and, pretty much every time that I tried it, you lose a bit of refinement and fluidity, and most importantly, an amount of musicality. I know, it’s a meaningless word, but I use it to describe that bridging can lead to a technically more capable amplifier but with a less involving sound. But that is not the case here.
The mono’d duo sounds every bit as fluid, refined, airy and subtle as a single amp in stereo mode. The overall presentation, though, is a little different. A stereo AMG-STA has a slightly sweet, subtly relaxed presentation with a midrange and upper bass that seem just a little mellow compared to the ST-10 as well as the CH A1.5 which is my reference in terms of absolute neutrality. The mono pair sounds even more linear. Mind you, despite what I wrote above, I feel that the stereo model is already one of the most linear amps that I have heard, so this means that the mono’d pair gets even closer to the ideal that, for me, is the CH A1.5.
I only wished that the connectors on the rear were arranged more cleverly and more spaced out, for instance by moving the fuse to the bottom. The overlapping “flap” makes for a clean look but makes connecting large spades effectively impossible.
Along with even better linearity and transparency the bass is tighter and more articulate in its upper range. Yup, precisely the area in which the stereo model could do slightly better. Although it takes a couple of minutes to adjust to the leaner and more neutral sound, I quickly found myself hooked to the new presentation. The relaxed and slightly warm quality of the stereo mode is gone but all of the refinement is preserved. More vital, immediate, rhythmically urgent and dynamically incisive, importantly, there is no tendency to dryness nor too much control. The bass is tight but also upbeat and punchy and the presentation is highly engaging, both cerebrally as well as emotionally.
Remember that I mentioned in part 1 of this review the ST-10’s advantage over the AMG-STA in terms of midrange communication and overall timbre? Well, even these aspects are improved with the switch from stereo to mono.
Going back to a single stereo unit I can imagine some people preferring its warmer and more relaxed presentation with certain systems and speaker combinations but in an absolute sense, two units simply perform at a higher level, not only in terms of audiophile parameters but also in a musical and emotional sense. For me, it is a no-brainer: two units are simply better than one.
The Acid Test
In the morning, with fresh ears and after having kept all amplifiers switched on overnight, I started playback from the Antipodes K50 via the C1 as before, using the pair of AMG-STA amps switched to mono. Boy, this was really good! Vocals are pure and rich, emotionally compelling and entirely convincing and the overall level of transparency and refinement leave nothing to desire. More to the point, there was simply nothing to criticize at all. If pushed, in my mind, I could imagine the CH possibly being timbrally a little more convincing and potentially slightly more robust. But otherwise, I had to conclude that I was totally happy with this performance.
So, what would the actual switch to the A1.5 still bring? As it turned out, dynamically, the cutie AMG-STA pair and the Big Swiss do not really differentiate themselves from one another. The differences are to be found in more subtle areas. For instance, harmonically-complex sounds such as rustling drum brushes stick out from the mix just a little more clearly and decay just a little longer, suggesting a higher-res and more naturally “analog”, just slightly more realistic sound. Along with this, I notice that, indeed, the timbre is more natural and the overall feel is more organic and acoustically convincing, which is most clearly heard with piano. Here, the harmonic overtones seem less glossed over and more differentiated from one another and the overall tonality is just that little bit more wooden or steely where it needs to be to make me believe that it is an actual instrument that is playing.
By the way, the bass was one other factor in which the A1.5 outperformed the AMG-STA. Well, although the Big Swiss amp is still a little bit more solid than the mono AMG pair, the difference really is not very obvious anymore. What’s more, although the AMGs have a linear power supply they still have the kind of upbeat vividness in the bass that comes along with the switched-amp territory. And I have to say, there is definitely something to it. The A1.5 is more solid and weighty but I can’t in all honesty still say that its bass is objectively better, more just a different rendition.
I should also stress that, while ultimately justifying the CH amp’s existence, these differences are far from earth-shattering. And given the rather ridiculous price difference, this speaks volumes for the AMG-STA.
Conclusion
The AMG-PRA + AMG-STA form a beautiful combo, not only visually, but also in terms of sonic synergy, the preamp’s robust and full sound perfectly complimenting the power amp’s slightly leaner balance. The combined result is a musically always engaging sound that is solid and full-bodied, smooth and refined yet highly detailed and transparent, with perfect pacing, and great dynamics. Honestly, at 3200 euro, I haven’t heard a better amplifier, either integrated or separates.
As great as the combo is, the AMG-STA power amplifier really is the star of the show. On its own, it is capable of performing on a level that is well and truly beyond what might be expected from an amplifier at its price point. To be more precise: if the preamp already performs at a level that belies its price sticker, the power amp steals the show as it has the ability to perform on the level of amplifiers that typically cost multiples of its modest 1.595-Euro price. I am not kidding!
Combine the AMG-STA with a great volume-controlled DAC and you’ll have a nearly unbeatable system. Between single and dual amps, if ever there was a no-brainer decision, this is it. The pair simply raises the performance in each and every audiophile parameter, without harming the emotional involvement.
As should be clear by now, I am definitely impressed by NuPrime power amplifiers. First, the ST-10 proved to be a keeper, then the ST-10 Monos proved that the concept could be taken further, then the AMG-STA proved that Class-D can be as “analog” and as refined as the best linear power amplifiers, and now, the pair of AMG-STA’s have further raised the bar. Although the ST10 and ST10 Monos still have their unique flair, as of now, the pair of AMG-STA’s are my personal reference in the field of affordable power amplifiers with true high-end aspirations.
Whether used as a single stereo model or as a double-mono pair, the AMG-HPA is an absolute HFA Favorite.
(AMG-STA power amplifier)
External Links
Manufacturer’s website: NuPrime
Distributor for the BeNeLux: Dimex
Dear Christiaan,
it’s always a pleasure to read your thorough reviews with comparisons to your and your friend’s reference systems, many thanks for your efforts.
I’m in search for a reasonable priced amp or mono amps and it’s really exciting what is offered nowadays. And it’s especially interesting when you decide to keep something as one of your favorites like the AMG-STA amp from Nuprime. You were also very enthused about the Audio-GD Master 2H mono amps. From what I read in your reviews about the Master 2H and the AMG-STA monos, is that both come quite near the level of your reference A1.5.
Please could you tell me what the main differences are in your opinion between the AMG-STA and the Master 2H? Are there quality differences or is it more a matter of taste?
I’m listening to all kind of music, from electronica to Japan Jazz from the 70ies, old music and a lot of other stuff. My system consists of a CH C1 dac like yours which I also use as a preamp and YG speakers which are at least from a construction point of view similar to your Magico S1. Due to budget constraints I can’t afford the awesome CH A1.5 which I’d prefer. Therefore I’m trying to come as near as possible to the A1.5 with a much cheaper solution.
From what I read about the Master 2H they are a bit lean in the bass regions, so maybe they are not the best partner for the rather neutral YG speakers, but I don’t know.
Besides the Audio-GD and the Nuprime amps I found two other interesting very reasonable priced amps – the new Denafrips Apollo and the new version of the Kinki EX-B7 mono amps. Would really be interesting to read a review about these amps from you.
Thanks in advance and continue with your great reviews
Michael
Alas, I have not heard them side by side. Between the M2H’s and the ST-10, the Audio-GD’s did perform better overall. But between the M2H and AMG-STA, I would say that it is mainly a matter of perspective and taste and secondarily a matter of power. Both are very linear, very transparent and highly refined and both have very accurate bass. The M2H’s, however, are understandably more authoritative in the bass. In that respect they come closer to the A1.5. The AMG-STA, however, especially when used as a mono pair, comes closer in terms of transparency and refinement. They are both very neutral and highly natural but the Audio-GD has ultimately slightly more convincing timbre. Although I don’t play extremely loudly and my speakers are not extremely demanding, the Audio-GD’s have much more reserves and so if you do play very loudly and/or have very demanding speakers, then the M2H’s will be the better option. Finally, I would not say the M2H’s are lean, they are very well-balanced and very accurate in my opinion. It’s probably more that many other amps (especially linear designs) are overly full in the bass (Bryston comes to mind). This may be a matter of taste and of what one is accustomed to but if the A1.5 is considered the golden standard then both the M2H’s are certainly not lean. And although they have slightly less authority, neither are the AMG-STA’s as a pair. Denafrips is an interesting brand but I’ve not yet heard their power amps. I’ve reviewed the Kinki Studio integrated and found it to be highly enjoyable but in a lower class than the A1.5. I’ve not heard the separate power amps (I may do a review someday) but from what I’ve read about them, they are voiced to sound sweet or colorful rather than neutral and I’d wager that they likely won’t outperform the M2H’s or a pair of AMG-STA’s in terms of neutrality, refinement and linearity. But please don’t take my word for this as it’s a gross guesstimation.
Dear Christiaan,
many thanks for your further thoughts and advice. The YG speakers are quite demanding, but I don’t listen very loud. So probably the AMG-STA are completely sufficient, especially as mono amps, but the speaker connections aren’t very convenient with spades.
From the reviews I read about the smaller Denafrips amps they are maybe warmer with less speed and detail than Audio-GD and Nuprime. The Kinki monos are maybe more in the direction of the A1.5, they changed a lot with the 2020 versions of their amps. I’m already very curious to read some reviews about the revised Kinki monos.
All the best
Michael
Do you have a cost effective Dac/Pre solution for a pair of AMG-STA amps ??
Thanking you in advance !!
I would suggest skipping the analog preamp and getting the best volume-controlled DAC that you can afford. There are many options! Also, NuPrime is working on an AMG DAC. Don’t know when it will be released but when it is, I will probably review it.
Hello,
Would the Lyngdorf CD-2 CD player DAC/Pre be a happy match for a pair of AMG-STA power amps ??
Best Regards,
Steve
Hi Steve, the Lyngdorf CD-2 does not have a volume control, or does it? But alas, I have not heard it and don’t really know the brand very well so will have to refrain from making assumptions.
Hello Christiaan,
Thank you for another excellent review! What is your impression of the suitability of the 2x AMG-STAs option for rock & electronic music? I read the following on the Nuprime website (& since I listen to a lot of rock & electronic music, I’m curious):
“Tonal qualities of the AMG STA leans toward being full and rich, so instruments and vocals seem to gain extra body, weight, and harmonic richness. It may not be the most accurate reproduction but does make Jazz and Vocal pieces highly addictive. It may take away the raw edge of Rock and Electronic music and sounds less exciting for some.”
I haven’t been able to achieve an exchange of my DAC-10 & ST-10 for 2x Audio GD 2H amps, as I hoped, so am now looking to exchange for 2x ST-10Ms or perhaps these 2x AMG-STAs instead. I have Wilson Benesch Precision P1.0s.
Best wishes,
Jason
Hi Jason, These are highly neutral audiophile amplifiers and I feel that the AMG-STA’s are suitable for all music genres. I listen to a lot of electronic music myself and they really do great. As I see it, rock also works just fine but some people are of the opinion that rock music requires some extra bass body, slam or roughness to sound right, and if you do too, then perhaps they are not ideal. But then, the M2H’s would not be ideal either, as both amps are clean and accurate.
I have read that bit of text on their website but don’t fully agree with it. Maybe what they are trying to convey is that the AMGs do not sound cold or sterile. As for taking away raw edge, well, I’d turn that around in that the amps do not add it, as some amps do. I think that both the M2H’s and the AMG-STA’s will work well with the Precision P1.0’s but I’d have to try both options to know which would be my preference.
You could also try the Anthem STR stereo amp, it’s not on the audiophile level as the aforementioned amps but it rocks like crazy.
Thanks for the excellent review.
Just a question. Which power cords did you use with the mono AMG STA and PRE?
Hi Christiaan, could you please tell me where I could get a set of these cables made for me. In exactly the same configuarion… Thanks!
Hi Gunther, I used Belden 19364 with Bals Schuko and Oyaide C-004 IEC. These are my go-to cables for my own components as well as review components. If I forgot to indicate this, and unless noted otherwise, it’s safe to assume I used these.
Hi Christiaan,
I have obtained two AMG STA amps to pair with my Audio GD Master 1 preamp. ?
Could you advise on the best way to connect these please? I have realised that the Master 1 has two 3pin xlr & two 4pin xlr output connections. The AMG STAs each have a pair of 3pin xlr inputs.
It seems that the options are either a 3pin y cable or to use rca. What did you use in your testing?
Best wishes,
Jason
Hi Jason, the 4-pin connectors on the AGD are for Current connections only. These are not compatible with regular voltage connections. Thus, you should use either the cinch or the 3-pin XLR connectors. In this case, I used cinch (Siltech Paris MXT).
Jason,
-as for connexions,
Balanced/XLR gave me better timbres than UNbalanced mode.
Note that I listen mainly to classical, less to rock.
-Nuprime’s website may say that “Tonal qualities of the AMG STA leans toward being full and rich, so instruments and vocals seem to *gain extra body, weight, and harmonic richness*. It may not be the most accurate reproduction but does make Jazz and Vocal pieces highly addictive”,
I can reassure you that they certainly do not add honey-topping on everything, producing a rosy-view of all recordings: my Harbeths M30.2 sound rich; with the AMG combo, they do not sound noticeably richer. The midrange is still full-bodied, and the image is more precise overall. So, it sounds more *realistic* than with my other amplifier.
See my post hereafter (23/8/21).
Thank you Christian. Did you use a y connector?
That’s not necessary. You simply switch the amplifiers to mono mode and then only need to connect one of the two channels per amp.
Thank you again, so does this apply to xlr as well as cinch connections? One connection from the AGD to the AMG STA?
Also, did you compare the sound performance of xlr vs. cinch in the context of using a Master 1 as pre & two STAs?
When the amp is set to bridge mode, both channels work as one and require only one input. The manual does not state anything re XLR vs Cinch and in this scenario, I also did not make a comparison. Usually, though, XLR vs Cinch is a relative matter, depening on syngery between source and destination, as well as a matter of taste. Balanced tends to sound larger and wider while Single-ended tends to sound smaller and more rooted.
Thanks Christiaan! I suspect I’ll prefer the former & there’s an opportunity to learn by trying the latter…
Hello Christiaan,
nice review.I’m plating with the B&W 804d3 and amNaim nap250dr.Do you think the Nuprime wil be a great match with the Bower’s?And Will thee have enough power to drive these speakers?
Hi Ronald, whether or not it is a good match will depend on your preferences because Naim and NuPrime likely have very different sonic perspectives. Technically, however, both the AMG-STA and ST-10 will drive the 804’s with no problems whatsoever. The former is airier, gentler, and more refined while the latter has a robust sound more in line with classic Naim. TBH, I have not heard the modern Naim amplifiers.
Say my ears are too old to get this right, or somehow the mix of equipment is making it too hard to make judgment.
Little history…. your, (not to worry, several other reviewers as well) review of the Bryston amps, specifically the 4b3 and how well it paired with Martin Logan’s. (mine, the 15’s) was the reason I purchased the 4b3s for my ML 15a’s. Love them…until.
I had a friend over who was convinced via your original NuPrime AMG-STA review to purchase them for his system. He brought a pair of them for duo mono.
He installed them in my setup….bypassing my 4b3.
Jeez…other than the pure bass power of the Bryston, every other sonic point seems to rival the 4b3. I even felt that the bass control was nearly as accurate, giving them an enhanced thump.
What really though was the big difference, midrange. The midrange seemed to fill a void i never knew existed.
I’m frustrated. These amps shouldn’t sound better.
Christiaan,
I recently discovered your website (and yourself, as a hifi reviewer). Wow! Great job.
Many thanks for that thorough review.
Afterwards, I bought the AMG PRA&STA combo for my Harbeth M30.2 Anniversary (for classical mainly, then jazz and a little bit of rock and electro). I attend to acoustic concerts regularly.
I had been offered the AMG PRA&STA combo for a home-trial. Your review convinced me that I was not at risk of loosing my time (I had a very strong prejudice against class D). My present amplifier is an old (but still good and recently revised) Marantz PM-16 (class AB, 80W, 20Kg). I needed a more compact and lighter amplifier.
The AMG PRA&STA combo is all that, but also more: AMG’s stereo image is much more accurate; the sonic rendering is much more detailed. Timbres are very good (in balanced mode, preferably). The so important midrange is a success (though class D, the STA doesn’t get the midrange leaner compared to the Marantz). Bass is very well controlled, without preventing any natural bloom of the instrument (i.e., cello).
Maybe there’s just the treble is not *quite* up to the level (in quality) of the rest of the range, but I am quibbling here as I perfectly can listen to baroque music with a lot of pleasure.
Overall, I am delighted. Concerts got me very demanding, and being able to listen to classical music (even baroque & early music) on revealing and neutral speakers as Harbeth M30.2 with that combo, is a proof of quality I think.
PS: you are an Apogee aficionado; I own a pair of Analysis Epsilon (+ Aries Cerat & YBA Signature Classic) in my main system 😉
Orfeo
Hi Orfeo, great feedback, that’s all nice to hear! PS: I’m currently reviewing two Aries Cerat components! 🙂 See my Youtube channel for a preview. https://www.youtube.com/watch?v=3AeTJPTTg2I and https://www.youtube.com/watch?v=YKD78q60jV0
Hi Christiaan,
Really enjoy reading your reviews. I purchased an AMG-STA primarily on the strength of your review fairly recently and I have to say your comments about the amplifier’s sound are spot on. I would never have considered this purchase had I not stumbled across your review as nuprime was an unknown brand to me. Needless to say, I am very happy with how my system sounds so thank you. I am thinking that I will add another STA down the road, but have one concern that I hope you can help me with.
To provide some context, my system consists of a Bricasti M3 DAC that I run directly to the AMG-STA using the volume control of the Bricasti. I have two sets of loudspeakers at the moment namely the Xavian Ambra Exclusiva with 88db sensitivity and another pair that is 95db sensitive. In relation to the 95db speakers in particular, do you think the high gain of the AMG-STA’s will present a noise problem or will the Bricasti volume control (which I understand operates in the analog domain) mitigate any noise issues there might be? Would appreciate any comments or insights you might have.
Thanks very much
Chad
Hi Chad, nice to hear that my review is helping people worldwide discover this still underestimated brand. The AMG-STA has no more noise than any other amplifier and DACs are typically also very silent, certainly when there’s an analog volume control in the circuit. So, I wouldn’t expect any issues with your 95dB speakers. However, it is my experience that high-efficiency speakers sound best when driven by low-power amplifiers, or at least amplifiers with not too high a damping factor. For instance, the Devialet 120 and 200 sounded fantastic with my Apogee Duetta Signatures but flat and lifeless with AvantGarde Unos. In your case, 95dB isn’t extremely efficient, but I’d still suggest to ty before you buy.
Christiaan,
Thanks very much for the helpful and quick response.
Chad
Hi Christian, my current setup:
– Pi2AES
– Holo Audio Spring 3 incl pre amp board
– Valvet E3 (pure classe A – 20 watts)
– Magico A1
– KEF KC62 subs
Though the sound is highly engaging I am missing the attack and speed for my Magico’s. In my opinion this is where the Magico’s can really shine.
Do you consider the AMG-STA (dual mono setup) as a step up in my journey to get the most out of my A1s?
Best Vincent
Hi Vincent, I’ve not heard the Valvet but I imagine that the AMG-STA does indeed sound faster. In general, Magicos like well-controlled and powerful amps. But if it’s specifically attack/impact you want then the ST-10 is likely an even better alternative. Also, do note that there is a new amp coming that will combine aspects of AMG and ST. No timeline yet but I will review it on HFA.
Thanks for your reply. It is not only PRAT where I am after, but also the combination with loads of micro dynamics and staging.. no doubt there will be an (even better) successor 😉 .. looking forward to your review.
Anyways, I got the AMG’s on my way for a try out at home.
Nice! Do let us in on the results!
Hi Christiaan,
Thanks a lot for these insightful and detailed reviews, you are doing a swell job here!
Similarly to Vincent’s system above, I’m also running a Holo Spring 3 (lv 2) with its preamp module as my frontend, however, the chain below is a bit more modest I would say:
– NAD M22 (v1) power amp
– Dynaudio Evoke 30 speakers
– Grimm TPR XLR interconnects and Tellurium Q Black II speaker cables
Would you consider something like the mono pair of the AMG-STA or ST-10M to be a potential step-up from the NAD?
In addition to Vincent’s comment above:
I feel that with the introduction of the Holo Spring 3 in my system I gained a LOT in terms of overall SQ, but lost a bit of slam, especially noticeable in some (but not all, depends a lot on the actual mix I believe) rock albums in the kick drum department (maybe due to the NOS nature of the Spring 3).
Cheers!
Csaba
Hi Csaba, given that the M22 is a very robust-sounding amp, I would not think the AMG-STA would make up for the lack of slam that you mentioned. The AMG_STA will likely further improve the finesse and subtlety but I don’t think this is what you are after. Rather, it might be worthwhile to consider changing DACs again. Sorry… I found that discrete R2R DACs and especially those of the non-OS, non-filtering kind are very pure and I like them for their precise bass. However, depending on what one is accustomed to, such purity can seem to lack vitality or grunt, compared to more “regular” DACs such as a Bryston BDA3 to name the first thing that sprung to mind.
Hi Christiaan,
I consider having the Holo Spring 3 in my system as one of the best upgrades I’ve had so far, so I intend to keep it for some time 😉
I guess it gave me a sense of what higher-end gear can do, so now I’m interested in additional upgrades down the chain – this is why I was curious if a pair of these Nuprimes (or the ST10M) would be an improvement over my NAD M22 amp.
Based on your comment I guess these won’t improve a lot on the M22, can you recommend something that might? Audio-GD Master 3A seemed like an interesting option as well (another potential demo at Magna HQ :))
My intention is not to fix the lack of slam, but to further improve my system’s overall sound quality.
I agree with your comment on the pure nature of this DAC, thanks for that insight. As I hinted above, I think it does a great job at revealing the actual mix of the recording and it doesn’t overemphasize anything if it’s not mixed that way from the get-go.
Hi Csaba, in that case, you could indeed look at the AGD Master 3, or even better, the M2H monos. Surprisingly, the NuPrime ST-10 has more low-end grunt than the M2H’s but the latter are more neutral and linear, and more refined. Against a duo of AMG-STA I’m not quite sure if the AGD’s are better in an audiophile sense, perhaps, but they are certainly more expressive. BTW, you might want to hold off on any definitive purchase because NuPrime will release a new amplifier that is said to combine aspects of AMG and ST. A review is planned for HFA.
Dear Christian,
Thank you so much !
First, from your review on Martin Logan, I have upgraded my old SL3 for ESL11A. Greater details, more precision, wider linearity from up to down.
I had few amps available in my home to listen them : old Krell KAV300i, Pass INT60 and Ayre V5ex. Nothing here was giving me full satisfaction for various reasons.
Then, I saw your review of the dual mono Nuprime AMG STA and I decided to give a try. What a great idea !
Amazing experience, and great combinaison. I’m just discovering discs that I thought I knew well for more than 30 years. So realistic, catching attention and emotion, with a great sense of dynamic, impossible to stop to listen disc after disc. Top performances with all types of music. High performances here, high satisfaction. The amps are directly connected to a DAC Totaldac with volume control. Great stuff. I was able to confirm your reviews.
I’m very grateful to you.
Hi Phil, this is great feedback, thanks for sharing!
Hi Christian,
Do you have any indiction price wise for the up comming NuPrimes? And should the be used in dual mono or stereo setup?
– I am able to pick up the AMG-STA’s for a very interesting price ☺️
Vincent, are you picking it up from somewhere in the NL? If so, then how much? 🙂
Please send me a email and I will inform you: vdvdv_1981@outlook.com
Hi Vincent, the new stereo power amp is called Evolution STA and it will cost 4.995 euros.
Thanks Christiaan! I noticed the model is already available on the NuPrime website and is for sale. Happy camper with the AMG-STAs for now though..
Initial impression of dual mono setup: Wow! Classe A resolution and detail combined with loads of classe D authority and PRaT. Call me impressed… lets see what some proper burn-in time will bring in terms of further improvements..
After some burn in time (approx. 150 hrs) the lower frequency regions got more definition and stage opened up.
I can totally echo the findings of this review: superb staging (holographic), loads of resolution/ refinement and most of all control: no matter how loud I crank up the volume, the presented music always stays balanced/ undistorted where all ‘hifi’ characteristics remain. Coming from a pure class A amp, I don’t feel I am missing any class A qualities with the AMG STAs. I found what I was after: authority and speed. Thanks! Curious how this combo compares to the Evo STA 🙂
Great feedback, Vincent! I will be comparing the new EVO STA to a single ST-10 and a single AMG-STA.
Very interesting…. but wouldn’t be a dual mono AMG-STA setup comparison be more fair?
I guess it depends on how you view it. The AMG EVO is a dual-mono amp internally, but it is a single unit. I feel it is fair comparing one single stereo amp to another single stereo amp. Besides, the ST-10 cannot be bridged. I don’t know, maybe, if the results call for it, I will request a second AMG-STA sample.
Hello,
Thank you for a great review! I am in the market for these AMG STA but wonder how they compare to the Classé Sigma AMP2 which have recieved good reviews as a linear amp with nice resolution, great musicality and som McIntosh sweet midrage. This amp is however a generation older and perhaps there is too much going on in the class D area making it ”fall behind ” performance wise..? I can get a new unit of AMG STA for the same money as a used Sigma AMP2.
My speakers are neutral sounding and 88dB sensitivity.
I have heard many Class-D amps, but not the Classé Sigma AMP2. So, I’m afraid I can’t tell you how they compare. What I can say, however, is that the AMG-STA has certain sonic properties that I do not hear in most other Class-D amps (refinement, air, flow) and that it might be leaner than the Classe (just a hunch), but it certainly does not sound cool.
I have heard many Class-D amps, but not the Classé Sigma AMP2. So, I’m afraid I can’t tell you how they compare. What I can say, however, is that the AMG-STA has certain sonic properties that I do not hear in most other Class-D amps (refinement, air, flow) and that it might be leaner than the Classe (just a hunch given my experience with Classe so far and given that they employ a proprietary circuit), but it certainly does not sound cool.
Hi Christiaan, completely off topic here: I know that the reviewing of protocols is not in your focus area, but have you ever heard of/ experienced the Diretta audio protocol in your chain? I came across this phenomenon via Gentooplayer (distri for RBPi) and fora (Audiophilestyle) and was curious to give it a try.. I was completely flabbergasted about the results… revolutionary I would say..
Alas, I have no experience with that. Please also note that I must limit my responses to the reviewed product in question, otherwise, the comment section takes too much time out of my day… Hope you understand.
Fully understood Christiaan. My apologies.
I am curious about the upcoming Evolution STA review you mentioned.. the first impressions are available on Asian websites.. can you say something about the timelines when your view on this amp will be published? Still a very happy owner of the AMG STA dual combo though 🙂
Actually… I just published the review:-)
Hello,
The gain becomes double in mono use : 26 (stéréo) and 52 (mono)
Does there affect musical restitution or on the output volume ?
Thanks, best regard from France 🙂
Nicolas
Hi Nicolas, I don’t recall hearing a difference in gain when switching between one and two amplifiers. My AMG-STA is currently staying with a friend so I can’t check. I have a feeling that the double amount of gain as quoted on the NuPrime site is a result of how it is calculated but I will see if I can get confirmation.
Hello Christiaan ! congratulations for your web !
I have a question. I have a Pass Xp20 pre, PLINIUS Sa 103 and Wilson Sophia 2 and 12″ sub in a 25m2 treated acoustically room.
I’d like to change my power amp for a Pass 250.8 but I think I prefer something “cooler” (class A is to much hot for a summer in Mallorca).
I like Plinius but I think it could be better, sometimes it’s a little bit edgy.
A pair of AMG STA are tempting because of the price (much more less than a pass power amp) and they not generate hot.
Do you think a pair of STA AMG could beat a Pass class A (or A/B) power amp?
Thank you very much
Hi Javier, it is not a matter of one beating the other as an AMG-STA and a big Pass amp sound very, very different. Incomparably so. Among others, the Pass sounds bold, rock-solid, earthy, and with a full tonality, while the AMG-STA sounds agile and light-footed, less tonally saturated, and comparably ethereal. But in any case, the AMG-STA will not be dry or edgy and it also does not get the least bit warm.
Hi Christian,
I read tests in the Italian magazine SUONO where they recommend to use two AMG-STA not as two mono amps but use their two channels (each) for vertical biamping. The same, they write, is true for the ST-10. Better use two of these this way instead of two ST-10M monos. This should give much better results. Can you confirm?
— Aries Cerat Incito preamp + AMG-STA power amp association? —
Did someone already tried the Aries Certa Incito (non-S) as a preamplifier, associated with the NuPrime AMG-STA power amp?
– the Aries Certa Incito is NOT fully balanced, but has an XLR balanced output.
– NuPrime AMG-STA’s topology IS fully balanced (XLR inputs, but has also RCA inputs).
My concerns:
-what about the very high 50Mega Ohms (!) input impedance of the AMG-STA?
-does it make sense to partner a fully-balanced power amp with a single-ended preamp (which then uses a “balancing circuit”, or transformer (?) to power its XLR output? The Aries Cerat designer mentioned something a bit special about the XLR output, IIRC, but I am not technically savvy, and do not remember the details anyway.
SPEAKERS: Analysis Epsilon (4 Ohms, flat), Harbeth M30.2 Anniversary (8 Ohms, min 6 Ohms)
MUSIC: mainly classical.
PRESENT POWER AMPLIFIER: YBA Signature “Classic” (= the 1996 model, revised), 100w, single ended, RCA.
I am aware that my question is a bit specific. So, “nobody is expected to do the impossible…”