Accustic Arts TOP POWER-I Mk3 135w/200w Integrated amp MM/MC phono & headphone

AA 02 IA TPOWER
NZ$ 16,250.01 ea (incl. GST)
Accustic Arts

High-End from ACCUSTIC ARTS® is expected to sound natural and detailed,

New
POWER I-MK3 HIGHLIGHTS:
Audiophile integrated stereo power amplifier with high output performance
8 selected MOS-FET output transistors of highest quality
Shielded and encapsulated 600 VA toroidal core transformer of premium quality for high output reserves; separate windings for preamp section, for power amp section and for right and left channel
Integrated, switchable headphones amplifier of premium quality
Very good smoothing thanks to more than 80,000 µF power supply capacity
High damping factor for perfect speaker control
Integrated protective circuit switches ascents off when clipping, HF oscillations or too high DC offset occurs
Constant low operating temperature due to generously dimensioned heat sink
4 x unbalanced high level inputs
1 x unbalanced input configured as "SURROUND-BYPASS"
1 x unbalanced preamplifier output
Premium quality relays and premium quality rotary switch with gold-plated silver contacts for the input selection
Encapsulated high grade volume potentiometer including remote-control
Full metal housing for optimum shielding
Front panel made of brushed aluminium; turning knobs made of massive and chromed brass
Optional high quality phono stage (MC/MM); RIAA precision: +/- 0,15 dB
ACCUSTIC ARTS® POWER I - MK3 is "Handmade in Germany"

Specifications

Reviews

Specifications

Inputs: 
4 x unbalanced high level inputs (RCA) 
1 x unbalanced ”SURROUND-BYPASS” (RCA)
Output: 
1 x unbalanced pre-out (RCA); 34 Ω
Headphones output: 
1 x metal female jack 6,3 mm; 34 Ω
Signal difference left/right: < 0.4 dB (from 0 dB to -40 dB)
Input resistance: 50 kΩ
Output Power : 2x 130w @ 8ohms / 2x 200w @ 4ohms
Total transformer power: 600 VA (watts)
Power supply capacity: > 80,000 µF
Rated power output: 
2 x 200 watts on 4 Ω (THD+N = 0.1 % / 230 VAC) 
2 x 135 watts on 8 Ω
Distortion (THD+N): 0.007 % on 4 Ω load with 1 kHz and 10 watts 0.0045 % on 8 Ω load with 1 kHz and 10 watts
Signal-to-noise-ratio: -96 dBA (ref. 6.325 V) – A weighted 
Damping factor: > 700
Dimensions: 145H x 482W x 450D mm 
Weight: approx. 22 kg 

Reviews

In the end, it looked pretty darned good to me. Track one down and see for yourself!
John Potis

REVIEW SUMMARY:
No matter what the speaker, the Power 1's bass remained highly damped and well handled. .....Air? Transparency? Ease? Edgy rhythms? The Power 1 gave me all of that in spades in an excellent balance of speed, articulation and harmoniousness......It should be obvious by now that when it comes to treble performance; I regard the Power 1 as the bee's knees particularly for a solid-state amplifier. In this regard, it is perhaps the best I've ever used. .....Through the midrange, the Power 1 was as transparent as just about any amplifier I recollect ever hearing. That means it's excellent for a high-powered solid-state amplifier and was in fact much more like the Art Audio Symphony II - pretty high praise indeed.

EXTENDED REVIEW:
Please note - this review is of the earlier POWER-I Mk-I model back in 2004 that has gone through 2 upgrade iterations to the latest and more powerful POWER-I Mk3 model:
 
I have to admit that as I removed the Accustic Arts Power 1 integrated amplifier from its box, it was hard not to be impressed. If bells and whistles are your style, you won't be quite as taken as I was - the Power 1 seems to be about clean "form follows function" simplicity. With the possible exception of the aluminium casework that substitutes for the ubiquitous black powder coat found elsewhere, the Power 1 is all business, no frills. At 48lbs., it's no flyweight either and at 5.7" tall x 19" wide x 17.7' deep, it's not what one could reasonably call compact. But it's extremely well finished, with a front panel that's as simple as function allows and merely sports a large non-stepped rotary volume control, a matching source selector and what at first appear to be three small LEDs. Closer inspection reveals one of those LEDs to actually be an infrared remote sensor. The others indicate power and protection activation mode. That's it.
 
Around back, the Power 1 displays high quality if relatively few connectors. In total, it can handle four sources, one balanced, three single-ended. If the Power 1 is short on input options, it does much better on outputs. The Amp 1 is a full-function integrated amplifier claimed to deliver 130wpc into 8 ohms and 190 into 4. It offers two pairs of preamp outputs, one XLR, one RCA. Accustic Arts' own Balanced Amp 1 can be used for bi-amping via the balanced outputs while the single-ended outputs can feed a powered subwoofer or unbalanced amp. Both pre-outs can be used simultaneously.
 
The speaker binding posts are of the high-quality shielded/ slotted WBT variety that usually gives me a tickle. However, the close vertical orientation with one pair directly above the other gave me some pause. Those using banana plugs won't have a problem (though the spacing prevents the use of double bananas) but I found that inserting spades upwards into the down-facing shielded slots proved difficult because of the cramped quarters. While normally just a one-time annoyance that most users won't have to worry about after initial setup, I still found that when using heavier and stiffer speaker cables, the lower connection required that I either bend the wire at a hard 90° angle to clear the shelf (difficult and unhealthy for the cable) or place the component such that the speaker lead could comfortably dangle past the rear edge of the shelf supporting the Power 1. The location of the binding posts isn't a deal-breaker but a simple sideways orientation of the slots plus a touch higher mounting of the lower terminals on the rear panel would be a welcome change. Lastly, the binding posts' close proximity to the IEC inlet didn't help matters as my JPS Lab's Kaptovator was too bulky for comfortable accommodation. Oh, did I mention that squeezed into the same proximity is the power switch? 
 
The other ergonomic peculiarity had to do with the aforementioned XLR input. The front panel labels the inputs numerically and sequentially, with 1 assigned to the balanced input. Since I use no balanced components, this meant that I only used inputs 2 through 4. It may seem silly but I found it somewhat disconcerting that my primary source was to be found as input 2 and source number 1 had to go unused. Naturally, this limited me to three 3 sources. For those assembling an all Accustic Arts system, these reservations will be rendered moot as their CD player and DAC both make use of balanced outputs.
 
Rounding out the feature set is the fairly small and lightweight remote control that's nevertheless milled from a solid block of aluminium and sports just two buttons for volume up and volume down effected via a motorised potentiometer, which is fine by me. Don't look for a balance adjustment - there isn't one. Again, that's fine by me. Accustic Arts isn't the first company to take note of the fact that audiophiles don't use balance controls. Don't look for a phono stage either - the Power 1 is a line-stage only. In short, the Accustic Arts unit is minimalist despite being an integrated amplifier. Did I mention that it's designed and built in Germany?
 
On the inside, the Power 1 boasts ingredients such as 8 selected MOS-FET output transistors "of the highest quality" as well as the exclusive use of Burr Brown ICs. The 550VA toroidal power transformer is magnetically shielded and encapsulated and said to incorporate separate windings for the preamp section, power amp section and left and right channels. The Power 1 is protected by an "integrated circuit" that switches off the outputs when it detects clipping or HF oscillations as well as too high a DC offset. From use, I was able to confirm the "constant low operating temperature due to a generously dimensioned heat sink integrated into the housing". The Power 1 was indeed fairly cool running and never got much more than mildly warm to the touch.
 
My ergonomical quibbles notwithstanding, the Power 1 operated without a glitch in practice and proceeded to produce seriously good music. While motorised volume control changes were mechanically audible at the listening seat when the music was at fairly subdued volumes, that failed to annoy. In fact, the infrared remote worked quite well and was able to perform from unusually wide angles. Despite a relative lack of exposed heat sinking, the Power 1 never once approached anything like worrisome temperatures even after some spirited listening sessions with the 4-ohm 87dB-efficient Ohm speakers.
 
Right out of the box, it was the Power 1's robust yet refined bass performance that impressed me the most. The overall personality was sweet and somewhat reticent - clean and transparent enough through the mids but noticeably sweet and rounded on top. As it turned out, this was not a harbinger of things to come. In fact, the out-of-the-box personality was the ying to the Power 1's once broken-in yang.
 
The Power 1 spent a lot of time mated to the absolutely superb Thiel PCS monitors and SS2 Smart Subwoofer combo (review forthcoming) despite the fact that this was, perhaps, the least optimum mating I had in the house. The length of time they did end up mated to one another was indicative of the fact that despite one minor reservation, the Accustic Arts/Thiel system was making some wonderfully pleasing music. The highly resolving Thiel tweeters put a reviewer's spotlight on the Power 1's treble performance, which in turn favoured the speakers. That is to say that the two combined for some of the most extended and smoothly illuminated treble I've ever heard in my room. Detail was wonderful with absolutely no harshness or edge. I've never before witnessed such detail and extension coupled to no downside whatsoever. Ever.
 
Moving down into the midrange, the Power 1's performance never balked or strayed from the righteous no matter the speakers in use. The Accustic Arts integrated performs nearly as well in the midrange as it does through the treble. Marked by excellent transparency and smoothness, the Power 1 is one amplifier that could well please those tube lovers who think that they could never live with a solid-state amplifier. The Power 1 does an excellent job of combining musical detail with a very high level of transparency and velvety smoothness. If the Power 1 is to be faulted at all, it will probably come from those who are looking for a higher degree of harmonic density, taking some issue with the Power 1's more ethereal presentation. That's not in any way to say that the Power 1 is light in its loafers or that it lacks meat on its bones. Neither is true. Through the midrange, the Power 1 is similar to a good 300B tube whereas some may look for more EL34-style colour and density. Without question, either tube offers superb midrange performance albeit of slightly different signatures. Regardless, I found the Power 1 pretty difficult to quibble about.
 
Though the Thiel SS2 Smart Sub is a powered subwoofer, it takes a high-level input from an amplifier's speaker outputs. This makes the main power amplifier responsible for the integrity of the subwoofer's input signal and in turn (and to a significant extent) for the signature of the bass that arrives at the listener's ears. Through the SS1 subwoofer, I came to the somewhat surprising conclusion that the Power 1 was highly detailed and damped yet somewhat lacking in real muscle. For some reason, the Power 1 didn't seem as happy to push the bass into the subwoofer as my Art Audio 845-based Carissa SET was. We're again talking about shades of grey and it wasn't to such an extent as to leave me feeling cheated. The opening drum whack from Aimee Mann's "Humpty Dumpty" [Lost In Space - SuperEgo Records SE-007] was never without its highly articulated and weighty gravitas - so much so that I usually hit the 'back' button at least once just to experience it again. 
 
Peter Gabriel's UP [Geffen 0694933882] is a very bass-heavy CD which anything less than superior control in the bass can leave overly heavy, slow and murky. Not so with the Power 1 - not so at all in fact. Bass was so controlled that you could find evidence thereof throughout the rest of the spectrum, with the entire CD exhibiting an extra helping of airy spaciousness. Despite the surrounding mayhem and chaos, Gabriel's voice always came across with almost a halo of space around it to keep it distinct and completely intelligible. Ditto for the rest of the instrumentation - the Power 1 did a super job of unraveling the pandemonium. If the Power 1 did perhaps not have the greatest amount of oomph, it certainly had the control of a quality amplifier.
 
Though its basic character remained essentially the same, things changed just a bit when I swapped for the Hørning Perikles speakers. By seemingly injecting them with a dose of steroids, the Power 1 took such a hold of the Perikles' dual 10-inch Beyma woofers that I was actually taken aback. Why would an amplifier drive a 'real' speaker load with more brute force than the resistive load of a subwoofer's high-level Z-coupler? I confess that I was stumped but pleasantly so.
 
Then the Hørnings' 96dB efficiency created another surprise. In my experience, big amplifiers often have trouble getting out of first gear with efficient speakers. This can actually leave small amplifiers to sound more powerful and satisfying into such loads. But not the Accustic Arts Power 1. It came across as both powerful and complete. In this regard, the Power 1 easily trumped my Bryston 7B-STs. For the first time in recent history, Danny Gatton's "Pudding And Pie" [Crusin' Deuces - Electra 9 61465-2] marked by a super-snappy rhythm, crisp percussion and deep and weighty yet sharply defined bass sounded exactly that way. This song's bass line has a way of purring and growling both at the same time. That can drone throughout the room when allowed to get out of hand. The Accustic Arts' complete lack of bass overhang lent both an extra measure of speed and agility to the song as I've not experienced it before. And this was presented to me on a soundstage as wide open and airy as imaginable. Image solidity was rock-steady and there was plenty of space and excellent depth around and behind the instruments.
 
Other than in the bass, the Hørning/Power 1 combo provided no further surprises, just listening pleasure. Like the Thiels, the Hørnings are equipped with a high-resolution tweeter, which again amply demonstrated the Power 1's treble attributes. Now ordinarily, I'm a midrange guy. After a speaker gets the midrange right, I look for some good bass. As far as treble, I'm often taken with speakers that, while not dark or overly sweet, may just err on the side of politeness. Better to play nice than to go out of one's way to expose warts and other shortcomings in recordings, sez I. But I have to also say that the Power 1 was doing a great job of showing me that extension and detail don't always have to equate brutal honesty. Chimes, cymbals and percussion instruments were portrayed almost stunningly present yet remained remarkably and surprisingly organic and non-irritating - somewhat paradoxical at least in my experience. Where I'm usually pleased enough with a treble that's smooth enough to commit no sins, I found myself more and more enamoured by what the Power 1 was bringing out of the music. 
 
When I let the Accustic Arts have a go at the 87dB/4-ohm Walsh 4.5Mk II -- a speaker more in line with the amp's 190-watt delivery into such a load -- it was late in the Power 1's stay yet it gave me more of the same. While I doubt that the Power 1 will be confused with any of the mega-watt bruisers, bass through the Ohms came across as properly linear, nicely detailed and, again, very much in control. No matter what the speaker, the Power 1's bass remained highly damped and well handled. My Ohms are still breaking in and though not quite the most transparent speaker I have in the house, the Accustic Arts amplifier held up its end of the midrange bargain with smoothly flowing detail and true instrumental timbres.
 
But guess what? Once more I was attracted to the gestalt of the treble. Don't get me wrong, the treble wasn't standing out from the rest of the musical spectrum - it was neither reticent nor too prominent, something that will turn me off in a flash. But it just seemed very extended and detailed while remaining utterly natural and musical in a way that I don't hear very often. In all my time with the Power 1, I never observed any hash, edge or unnatural luminance and this was achieved without throwing instruments back in the shadows or bringing them too much to the fore. "Highway On Sunday 51" from the Aimee Mann disc had musically tight and focused air about it. Rumbling bass and subdued percussion along with steely guitars were clustered around the immaculately intelligible vocals while it all remained separate but part of a musical whole. Though clean and transparent, it avoided sounding artificially hifi-ish. For that I have to credit an unusually high degree of transparency that lacked any aforementioned edginess.
 
"Tragedy" from the Danny Gatton disc offered yet another such demonstration. I found myself coming back time and again to this cut just because it sounded so captivating. I came back for its array of colours and textures that placed the Power 1 in such an excellent light and just sounded so damned good. Air? Transparency? Ease? Edgy rhythms? The Power 1 gave me all of that in spades in an excellent balance of speed, articulation and harmoniousness.
 
Comparisons 
 
It should be obvious by now that when it comes to treble performance; I regard the Power 1 as the bee's knees particularly for a solid-state amplifier. In this regard, it is perhaps the best I've ever used. It illuminated treble details as no other amplifier I've heard, including the 300B-based Art Audio Symphony II, my other high-water mark of an amplifier. I'm not prepared to say which one I'd rather live with for the long term simply because while each is excellent, they are also slightly different. The Symphony II is subjectively as extended and detailed yet remains somewhat more ethereal and heavenly while the Power 1 sounds more concrete, earth-bound and business-like.
 
Through the midrange, the Power 1 was as transparent as just about any amplifier I recollect ever hearing. That means it's excellent for a high-powered solid-state amplifier and was in fact much more like the Art Audio Symphony II - pretty high praise indeed.
 
In the area of imaging and soundstaging, the Power 1 excelled at recreating large and spacious venues with excellent image density. I've never heard the Power 1 significantly bettered if at all. And by now I think I should have made my case for the Power 1's bass performance fairly well. No, it won't be mistaken for one of the big Krells or Levinsons when it comes to power and slam. But I found it more than reasonably linear while being exceptionally well controlled. And of course it doesn't cost what one of those Krells or Levinsons would, either. Just how much muscle it will display will be somewhat dependant upon the chosen speaker and, as with any amplifier, an audition with your speakers is a good idea.
 
The Accustic Arts Power I integrated is not an inexpensive amplifier. On the tongue-in-cheek dollar-per-pound value scale, it may even be a hard sell. But I keep reminding myself that I had replaced my $9800 pre/power combo of Shindo Partager preamplifier and Art Audio Carissa and enjoyed two gains (8 x as much power and that endearing treble articulation) and only minor losses. On that basis, it's a much easier case to make. Throw in the convenience and economy of both a synergistic pre/power section (guaranteed by all integrated amplifiers); one less power cord and interconnect to worry about -- not to mention the need for one less shelf when it comes time to upgrade your equipment rack -- and the Accustic Arts Power 1 integrated amplifier just keeps looking better and better. In the end, it looked pretty darned good to me. Track one down and see for yourself!
………John Potis