Amp/Preamp Asylum: REVIEW: Musical Fidelity A308cr Amplifier (SS) by readargos

Model:	A308cr
Category:	Amplifier (SS)
Suggested Retail Price:	$3595.00
Description:	Dual Mono Power Amplifer
Manufacturer URL:	Musical Fidelity

Review by readargos on August 08, 2014 at 19:48:08
IP Address: 67.175.6.2 Add Your Review
for the A308cr

I’ve been a fan of Musical Fidelity gear since I bought the original A3cr pre/power combo after reading Sam Tellig’s review in the October 2000 Stereophile. I lived with the A3cr, the A3.2cr, and now the A308cr. Talking to a Musical Fidelity insider, I was told these series are essentially the same circuit. The design originated with the limited-edition Nu-Vista products of 1999 and trickled down to regular production units. The A3 series ruled the roost from 2000-2002, replaced by the A3.2. The A308 series was produced concurrently with the A3.2 from approximately 2002-2004. The A308 was the top-of-the-line regular production model, and represented the most fanatical implementation of the circuit, short only of the limited edition Tri-Vista kW amplifier. The A308 series is some of the best components Musical Fidelity made, winning Product of the Year Awards in both the U.S. and U.K. audiophile press.

These components represent what I think of as the classic Musical Fidelity sound that, for the better part of a decade, won rave reviews and loyal fans worldwide. The company had hit its stride. I think the choke-regulated power supply (the “CR” in the model designations), adopted from tube amplifier technology, was a big part of the sound quality, “choking off” power supply grunge and high-order harmonic distortion, while leaving behind a benign amount of second-order harmonics. The basic sound of all of these units was wide open, with low noise, extremely high detail, harmonic integrity, tonal purity, and a beguiling smoothness. The A3 series is a bit warmer; the A3.2 and A308 are closer to strict neutrality with a slight tendency toward brightness.

What do you get with the A308 preamp over its lesser stablemates? The A3/A3.2 preamps are already extremely good, delineating a large soundstage, rich with the harmonic overtones of instruments that I hear live at the symphony with close seating, and showcasing the air and ambience of the recording venue. The A308 delivers more listening ease, an even larger and deeper soundstage with deeper bass and more slam. In direct comparison, it removes a sense of listening through electronics. This last point is subtle – you won’t hear it until it’s gone. It’s that greater sense of ease. What you’re really hearing, I suspect, is the benefit of the larger power supply. The A3/A3.2 could output about 3 watts Class A power; the A308 5 watts.

There’s a little more to the story of the A308 power amp, which is the focus of this review. The original A3cr amp was something of a curiosity in terms of its power rating and current delivery. Driving the full-range JMlab Electra 926 (heard at a dealer demo with one of my two A3 amps), it seemed unburstable. However, “average” sensitivity loads like the original Sonus Faber Concertino and B&W 602s required two A3cr amps to come alive. A single A3cr also lacked the juice to drive 4-Ohm loads like Magnepan satisfactorily. Musical Fidelity recognized the limitations of the A3cr, and made provision for biamping. The company also attempted to build up the A3cr with the A300cr power amp. It increased per-channel power from 120 watts to 225 watts, but reportedly lost some of the magic, sacrificing speed and resolution. While the A3cr was rated Stereophile Class A, the more expensive, more powerful A300cr was “only” rated Class B. Ratings aren’t everything, and it’s easy to imagine the more powerful amp shining with the right speaker load, but it serves to illustrate a point.

The solution Musical Fidelity found was to build a completely separate input/driver stage with its own power supply. The company claimed that at low power ratings, an amp’s driver stage was spotlighted, so they designed a driver stage with low distortion, low phase shift, low noise, low feedback and Class A operation. This driver stage permitted a high power Class A/B output stage to maintain the speed, subtlety, and delicacy of a low-power amp. In a rare example of trickle-up technology, even the limited edition Anniversary Tri-Vista kW amplifier implemented the same technology, with a Class A input stage and a bridged output stage to meet its 1,000-watt specification. While it’s great to understand the “why”, the question is, did Musical Fidelity succeed in its design aspirations?

For me, almost a decade on, the honeymoon period hasn’t ended. The A308 offers a good measure of the harmonic richness, instrumental overtones, and palpable air and bloom of tubes. It captures the resonating body of instruments, from high woodwinds to large bass drums. When an orchestra swells, it catches you up in a riotous swirl of sound. This is a beautiful and exuberant sound. It's a little brighter, giving the sound lift (the sense of a rising treble component on the note’s tail) with a long decay. Lift aids bloom and billowy air. By bloom, I mean the sense of instruments or vocalists being surrounded by a halo of air that grows and builds in proportion to the loudness at which they’re playing. Billowy air is related: the collective bloom of an orchestra in full cry, for instance, sends waves of sound surging toward the listener – all that instrumental resonance en masse. When the music stops, there’s a palpable decay as the notes die out and the hall absorbs the sound. This brighter, more colorful sound, coupled with a more forward presentation, seems to convey more vocal nuance and expressiveness. It emphasizes a bit more angst or sadness or yearning in the strings. However, as with tubes, it can also overlay the sound with a subtle haze or fine mist – the halo of the bloom – that limits the absolute crystalline transparency of some transistor designs, but more than makes up for it with palpable atmosphere. No, it’s not as overtly warm or romantic as some tube designs, nor does it have as liquid a sound as Class A transistor designs, yet you’ll still hear every vocal nuance.

Playing "The Concert Sinatra" LP (Mobile Fidelity) through the Musical Fidelity, Sinatra stands close, as though he's at the plane of the speakers, his image as big and tall as you’d expect in life. (The MF renders height rather obviously, taking the top off of the listening room.) Sinatra is bathed in the air of the studio. You hear not occasional reverb, but the air wax and wane and bloom around him with the intensity of every note. The orchestra spreads wider than the speakers, behind the rear wall, sounding loud and present. When the music stops, it takes 2-3 seconds for the notes to die out. Most electronics will get about a second of that decay. It’s very much a you-are-there perspective. The Musical Fidelity is more like a giant open vista (window seems too small a word) into the recording venue. It's open in the sense that someone not only threw back the curtains, but took the roof off and knocked down the walls. It’s like looking into a near life-sized, illuminated diorama.

It definitely sounds bright compared to most electronics, but there is no etch. It’s extended, yet smooth, and still conveys the grit of rock recordings, especially on vinyl. It is not bright in the sense of harsh, but bright in the sense of sunny, open, and clear, where the entire stage is spotlit. Most gear spotlights what's happening at the front of the stage and gets dimmer, less dynamic, or both as you go back. The MF spotlights what's happening in back with brightness and dynamics equal to what’s happening at the front of the stage. Some gear presents a deeper soundstage, but generally with a more distant perspective, where the soundstage starts behind the plane of the speakers and goes back. The MF’s soundstage starts before the plane of the speakers and goes back

This raises the question of whether the Musical Fidelity, with its bright, open sound, is causing a slight shift in timbre, inducing a slightly higher pitch, possibly resulting in a homogenizing of the sounds of certain instruments (particularly higher-pitched woodwinds and brass); or is it simply more open and extended than most gear, and thus more neutral and truthful? The Musical Fidelity is simply bigger, louder, and closer throughout the treble, midrange, and bass. The sound is consistent, however, and I think the difference is one of perspective - things sound brighter closer up. Its sound has a bracing immediacy. When I hear the MF’s warmth and bloom and rightness in the power range of an orchestra, it does not sound bright, but very much like what I hear live.

However, as several of the professional, magazine-published reviews reported, I've discovered that choice of cabling is important. The wrong wire can impart whiteness to the Musical Fidelity and bleach harmonics, but the whiteness is not inherent in the electronics. With good cabling, any instrumental homogenization disappears, even on CD playback. The whiteness disappears, while the brightness, the lift, the long reverberation trails, and the mild haze cohere into something more. On certain recordings – many, in fact – they recreate the atmosphere of the recording venue, which presents us with the aforementioned vista. Within that vista is not only the recorded ambience, but also newfound low-level details, the mechanics of instruments that I hear live with close seating, and greater expressiveness in playing and singing. Each venue is unique, so I’m not talking about a generic haze persistent through all recordings. All that information is on the recording, but very few electronics are capable of recovering it. The low-level details and constant presence of the venue as a "performer" make me decide in favor of the Musical Fidelity gear as simply being more open, more transparent, and more honest, with a level of neutrality and near lack of tonality that is almost hard to swallow. In some respects, you don’t hear what it does so much as all the things it doesn’t do, so much does it get out of the way.

It’s tempting to say the sound of some electronics is built from the bottom up, while being a little dark on top at the sacrifice of air and bloom and palpable decay; and the Musical Fidelity sound is built from the top down, while being a bit less tight, less solid, and less defined in the lowest registers. But back-to-back comparisons do not reveal that to be entirely the case. Rather, I think the difference is attributable to the MF being airier in the bass. The MF is fast, hard-hitting, and has the same air and bloom around tympani or kodo drums at the rear of the stage as it does strings and vocalists at the front of the stage. Playing Tan Dun's "Symphony 1997" (Sony CD), the big kodo drums are hard hitting. Better yet, Track 3, “Night Fight”, from the “Crouching Tiger, Hidden Dragon” soundtrack (same composer and label). When the drums come in, you’ll hear two, one left, and one right. Then the second pair of drums comes in, closer in perspective, and slightly farther to the left and right. Finally, the third pair, again closer and farther apart. There’s palpable air and bloom around each of the six drums, forming a V-shape. Then a seventh, even larger drum, centered and behind these six – the point of V – comes in. When I saw “Crouching Tiger” at IMAX Navy Pier, after the night fight scene ended, an excited audience member exclaimed, “Fuck yeah!” That’s about how you’ll feel after hearing this track through the A308.

While some gear seems more transparent, I think this is often a result of a slight leanness that allows detail to be heard more easily and emphasizes depth, but at the cost of both atmosphere and the weight in an orchestra’s power range that we hear in real life. Using Tan Dun's "Symphony 1997" (Sony CD), the large bells that open the work shimmer and resonate palpably. With the Musical Fidelity, you feel the resonance of the bells, and that resonance has legs: it walks around the room, and won’t sit down. By contrast, on gear that lacks midrange power for the perception of more detail and greater depth, no amount of volume will restore the full weight of those bells.

I find depth well rendered on the MF, though consistent with its more forward perspective. Running all Cardas also brings up the texture and musical tension to the level of gear that excels in those areas, allowing the MF better to convey menace or dread in music. (Without running all Cardas, the MF is airy and harmonically rich, but lacking somewhat in density and texture.) Woodwinds, strings, triangles, gongs, clacking noises, and large drums are just about perfect, with a good combination of transparency, sharpness, palability, and richness. Piano sounds big and rich and more harmonically developed on the Musical Fidelity, but this is not at the expense of detail, because, on good recordings, you also hear the click of the keys and the felt under them. Brass rends the air, while low brass, like tuba, has a palpable weight. Although the MF A308cr does not sound overtly warm compared to my memory of the A3cr, it conveys the natural warmth of an orchestra. The MF has a wonderful power range, so when the orchestra gets cranking, you experience it much as you do live: a palpable warmth and richness. It’s a physical response. Some gear is better at tracking different instrumental threads in a mix, so you sense all the contributions, whereas the MF focuses more on the lead instrument, while accompanying instruments are rendered a bit more as supporting harmony. However, in instrumental solos, such as those of violin or woodwinds on "Scheherazade" (Analog Productions RCA Living Stereo LP), the MF's focus on the lead/soloist is more like I hear live. I think the MF is slightly closer to a concert, where, from the audience, I tend to hear more of a blended sound, especially with my eyes open, but if I close my eyes and try to pick out the different elements, I find them all present. As well, solo instruments and singers are definitely spotlighted in concert, where, for concertos and various oratorio/lieder, the performer(s) are typically situated by the conductor's podium.

I should also state how clean and dynamic is the power delivery of the Musical Fidelity gear. Even when playing music at levels loud enough to damage a woofer (levels that are obviously loud), it's so clean and clear that it never sounds loud because it never sounds harsh. (I had set an MM phono cartridge for MC, so the A308 is not to blame from the damage!) This also decides me in favor of the Musical Fidelity being clean and open, as opposed to an unnatural brightness that shifts pitch or timbre. Other gear, including a lot of expensive gear, quickly reaches a point where it sounds loud because there's something that irritates the ears (solid state) or goes into soft clipping and gets a little wooly in the bass (tubes and some tube-hybrid designs). Direct-coupled solid-state designs often create a kind of staccato sensation, like that of a machine gun, with their emphasis on pistonic control of the speaker drivers – it’s like listening to a power station. You can overcome the clipping in tube designs with really high-power units, but then you're looking at $10,000/pair 200-watt monoblocks or the like. With solid-state, well, I don't know. I haven't heard anything else quite like the Musical Fidelity in terms of sounding loud without inducing listening fatigue with dynamic speakers.

The clean power and dynamics is one way in which the Musical Fidelity creates tension, because you kind of worry how loud it's going to get when the full orchestra is cranking. I’m a fan of electronic music, as well, and whether we’re talking Bjork, Portishead, Kruder & Dorfmeister, or Massive Attack, the A308 has the slam you want in the bass, and the detail and atmosphere to recreate huge artificial soundscapes, while delivering a full measure of the emotional response those soundscapes are designed to evoke.

Short of remote turn-on, the ergonomics are first class for a power amp. It has two sets of switchable RCA preamp inputs. This facilitates integration with a surround processor as well as A-B comparisons of different preamps. It also has a line-level RCA output, which can be used to power a subowoofer, as well as for biamping – perhaps with a second Musical Fidelity amp. Finally, it has two sets of speaker outputs for external biwiring. This could allow one, for example, to use a warmer cable with more touch and texture for the mids and highs (e.g., Cardas Quadlink) and a more dynamic cable for the bass (e.g., Cardas Neutral Reference) to tune the sound of your system.

The limitations of the Musical Fidelity gear lie mostly in choices made by the manufacturer. From the beginning, the company sought to deliver world-class sound quality at affordable prices – at least in terms of the pricing of high-end equipment. To do so, the company makes bulk purchases of components and uses the same casework across a product line (so the A308 integrated, pre, power, and CD player, for instance, inhabit the same chassis). The company also relies on its circuit design rather than audiophile-grade parts, such as expensive capacitors, which company founder Antony Michaelson has suggested are “bullshit components”. However, with the A308 power amp, the capacitors have been known to leak with age, and so need replacing. If you own the A308, or are shopping for a used one, it’s something to be aware of. Cheap capacitors are also responsible for some of the tendency toward brightness.

This mode of manufacturing has resulted in extremely high sound quality at reasonable prices, but it also means that production runs are limited by the amount of bulk components purchased, that each series of components has a short life cycle, that products sell at close out pricing more frequently, and that older models cannot be upgraded to the latest specifications. It has also led to a robust market for modifying Musical Fidelity gear, typically replacing the bulk-purchased capacitors with the “bullshit” audiophile-grade components, among other things. Even Musical Fidelity has gotten in on the game with their own Fine Tuning program. Compare this to manufacturers like Balanced Audio Technology and Ayre, where products may enjoy a decade-long life cycle, and refinements in the basic design can be retrofitted to earlier production models. I think this level of service and product longevity is good for building stature and customer loyalty as a high-end brand. The lack of it may explain why, even though Musical Fidelity builds excellent sounding components, including some cost-no-object designs with elite price tags, it does not enjoy the same reputation as more vaunted brands.

The A308 gear seems to combine the best of the tube world (high-frequency air and bloom, harmonic overtones and long decays, harmonic complexity and rightness, and truth of timbre) with the best of the transistor world (higher-efficiency Class A/B output stages and greater linearity); the best of low-power amps (a certain sweetness and delicacy, speed and immediacy) with the best of high-power amps (low-end extension, slam, and huge dynamic swings). It’s not as romantic or liquid as some gear, and lacks the ultimate sense of touch and texture of tubes, but this can be improved with choice of cabling.

Musical Fidelity – a company that has built tube, tube-hybrid and solid-state designs – represents a unique approach in the high end. There's that joke about the two blind men who describe an elephant, but one feels the animal's head, while the other feels its hind end. Both men are right, illustrating that the truth can have many sides. In the pursuit of audio excellence, there are many interpretations of the truth with different emphases, and people buy products based on which emphases are important to them, and which tradeoffs they are willing to accept. While no amplification is perfect, I think the A308 gear tells more sides of the sonic truth that most, especially compared to anything anywhere near its price point. It creates a sense of palpable atmosphere that I’ve only heard equaled by very expensive systems. I've worked with it for years, and I'm finding that I don't have the measure of it yet. I can make my system sound less bright and more closed-in, but I don't want to. It's a devil's bargain, and I lose too much in the trade.

Product Weakness:	No remote turn-on; the sub-bass isn't quite as good as a Krell.
Product Strengths:	Wide open sound, with plenty of power, low noise, extremely high detail, harmonic integrity, tonal purity, palpable atmosphere, and bass slam.

Associated Equipment for this Review:

Amplifier: Krell KAV-2250, Musical Fidelity A308cr
Preamplifier (or None if Integrated): Musical Fidelity A308cr, Krell KAV-280p
Sources (CDP/Turntable): Rega P3-24 with external power supply, Ortofon 2M Bronze, Tangospinner RP6 subplatter and RP6 glass flywheel platter, Musical Fidelity A308cr; VPI Scout SE with Soundsith Carmen
Speakers: JMlab Electra 915.1, Polk RT8
Cables/Interconnects: Cardas Quadlink IC, Speaker & PC, Cardas Neutral Reference Speaker, Signal Cable Silver Reference, Silver Cable Magic Power, Signal Cable Digital PowerMapleshade Clearview Ultrathin Plus, Monster, Homemade
Music Used (Genre/Selections): Classical, Jazz, Rock, Electronica
Room Size (LxWxH): 17 x 12 x 9
Time Period/Length of Audition: ~9 years
Type of Audition/Review: Product Owner

Amplifier:	Krell KAV-2250, Musical Fidelity A308cr
Preamplifier (or None if Integrated):	Musical Fidelity A308cr, Krell KAV-280p
Sources (CDP/Turntable):	Rega P3-24 with external power supply, Ortofon 2M Bronze, Tangospinner RP6 subplatter and RP6 glass flywheel platter, Musical Fidelity A308cr; VPI Scout SE with Soundsith Carmen
Speakers:	JMlab Electra 915.1, Polk RT8
Cables/Interconnects:	Cardas Quadlink IC, Speaker & PC, Cardas Neutral Reference Speaker, Signal Cable Silver Reference, Silver Cable Magic Power, Signal Cable Digital PowerMapleshade Clearview Ultrathin Plus, Monster, Homemade
Music Used (Genre/Selections):	Classical, Jazz, Rock, Electronica
Room Size (LxWxH):	17 x 12 x 9
Time Period/Length of Audition:	~9 years
Type of Audition/Review:	Product Owner