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Equipment Review

January 2003

Marsh Sound Design MSD-A400s Stereo Amplifier

by Tim Shea


Review Summary
Sound Bass was "deep and strong," while "the mids and highs [displayed a] smooth and refined nature"; offers "a very coherent and realistic musical picture, and while there was detail aplenty, it was always natural musical detail rather than the more distracting detail for detail’s sake"; "lacked a little force or power" in the midrange, however.
Features "The A400s runs in class AB…with 200Wpc on tap into 8 ohms and 330Wpc into 4 ohms"; fully balanced but does accept single-ended input.
Use Must be used via its balanced inputs to hear its full capabilities; a deep amplifier that will not fit easily on every equipment rack.
Value "At a retail price of $2295...you get quite a lot for your audio bucks."

Synergy: an oft-stated term bandied about by audiophiles that is so hard to find among audio components. Audiophiles inherently like to talk about their gear or the gear they’re going to get to replace their current gear, but I think it is actually synergy that underlies much of what really drives us as audiophiles. Let’s face it -- once you’ve spent five or ten grand or more on a given component (or in many cases considerably less), how much better does performance really get? Yes, it almost always can get better, but diminishing returns are certainly at work. More often than not we audiophiles say something is "better" or "worse" than something else when it would be much more accurate to call it "different" instead. The defining point is that a certain piece may work better or worse in your system and for your tastes, but is it really better? Who’s to say?

In an apparent effort to create synergies from both sound and business perspectives, electronics maker Marsh Sound Design and speaker manufacturer Soliloquy have joined forces, and now Marsh electronics and Soliloquy speakers are marketed together. Interestingly, Marsh and Soliloquy both design their products in the US, but Marsh uses cost-efficient manufacturing facilities in the Far East to allow them to provide higher-quality products at lower cost than if everything were done domestically. My hope was that the powers that be actually listened to the stuff together and found synergistic magic before they started comparing balance sheets and income statements. Since I use Soliloquy speakers in my reference system, I was really looking forward to doing a review where at least a couple of the components have been pre-certified to play nice with each other.

What I’ve slowly and painfully come to realize is that unless you’re building something like an all-Linn or -Naim system, where a manufacturer creates every link in the audio chain, you’re just bound to find inconsistencies somewhere. For me, this is really what makes writing an honest and objective review so hard (this is where you’re supposed to shed a tear for the poor reviewer), and I was really looking forward to not having to stress out quite as much about synergy just this once. Of course, I look forward to a lot of things -- but this doesn’t mean I get ’em.

Description and setup

Marsh Sound Design sent both the A400s stereo amplifier and P2000b preamplifier for review, but I’ll focus on the amp here and put the preamp under the microscope in the future. The A400s, $2295 USD, is quite a beast, measuring 19"W x 7 1/8"H x 18 1/4"D and weighing in at a hefty 45 pounds. What’s most noteworthy for me is the depth of this sucker, mostly because I was barely able to fit the amp on my standard-sized equipment rack. One more inch and Mr. Amp would’ve met Mr. Floor. Thankfully the thoughtful folks at Marsh spec’d the heatsinks with rounded corners, so moving the amp didn’t result in any blood loss but did improve muscle tone.

Because the amp is somewhat on the large side, it helps that it is very attractive in a simple and understated way. The front panel is brushed aluminum with an on/off button and a blue power indicator, and that’s pretty much it. Around back are pairs of single-ended and balanced inputs. The only disappointment was the speaker binding posts, which sported the plastic caps I associate more with mainstream A/V receivers than better separate components. Of course, there was also an IEC connector to allow for power-cord experimentation.

Speaking of internal components, the A400s runs in class AB, and with 200Wpc on tap into 8 ohms and 330Wpc into 4 ohms, there aren’t a whole heckuva lot of speakers this amp won’t drive with relative ease. Also, with an input impedance of 56k ohms unbalanced (4k ohms balanced), the A400s should get along fine with almost any preamp you might choose to throw at it. Obviously from these stats you can glean that the A400s is capable of running single ended or balanced, and according to Soliloquy when the balanced inputs are chosen the amp runs balanced from end to end. So at first blush, the A400s has the goods to settle right into any high-end system quite comfortably, yet at a retail price of $2295, it also looks as though you get quite a lot for your audio bucks.

In the real world, the A400s was user friendly and easy to live with. Even when run well into its considerable range of capabilities, something I did fairly often, the A400s got no more than warm to the touch. I like to leave my audio equipment powered on unless I’m leaving for more than a day, and I never felt like Greenpeace was going to come knocking at my door for keeping the A400s all warmed up and ready to go.

Although I initially tried the A400s with my Rotel preamp with good results, for the majority of the review I kept the amp paired with its sibling P2000b preamplifier. Maybe not surprisingly, there was some synergy there, and the P2000b also allowed me to run both single ended and balanced connections between amp and preamp. As it turns out, this was critical to the review -- read on.

Synergy swamp

I was both intrigued and a little disappointed with the sound I was getting from the A400s at first listen. There were some nice things going on in the midrange and treble, but overall the sound was a little soft and less than fully transparent. What was more disconcerting was that the bass was overpowering and behind the pace of the music such that it seemed, shall we say, bogged down. So much for synergy, I thought. I listened to this setup for quite a while, hoping that a good helping of break-in would dredge the swamp, but to no avail.

In my anticipation of hearing what I hoped to be a beautiful partnership between these amp/speaker kissing cousins, I forgot that Soliloquy made a point of telling me to make sure to try the balanced connections in addition to the single-ended inputs. They assured me that it would make a significant improvement, but I pretty much dismissed this as manufacturer enthusiasm and/or hype. Fortunately the good folks at Acoustic Zen were nice enough to lend me a balanced version of their Matrix Reference interconnect, which I use in RCA form in my review setup. While cursing the Soliloquy/Marsh people for putting me into what was shaping up to be a very uncomfortable situation and review, I half-heartedly inserted the new interconnects fully expecting to be under-whelmed.

No sooner had I pushed the play button than I found myself eating all the curse words I had muttered just seconds before. What I was now hearing did not even sound like the same amplifier. At once the bass, while still deep and strong, tightened up and snapped in line with the rest of the music. The mids and highs retained their smooth and refined nature, which was a good thing, but now they were accompanied by a larger helping of detail and air along with noticeably sharper attack and better transient snap. With the clearing away of all the cobwebs came a crystal-clear view of what was happening within the soundstage, and the resulting increased sense of dimension and space was startling and refreshing. The A400s was now painting a very coherent and realistic musical picture, and while there was detail aplenty, it was always natural musical detail rather than the more distracting detail for detail’s sake.

But still I was a little skeptical at the absolute level of change brought about by simply switching from single-ended to balanced operation between the preamp and amp. My skepticism led me to call Acoustic Zen just to make sure I was comparing apples to apples here, and sure enough, there were some running changes that had been incorporated into the balanced Matrix Reference cable that were not in my original single-ended version. OK, so this may explain some of the detail and perhaps a portion of the bass improvement, but the overall improvement I heard was more than I would have expected from upgrading an interconnect. Not surprisingly, the S/N ratio is considerably higher in balanced operation, so my best guess is that although I was hearing the benefit of an improved cable that worked better with the A400s (that synergy thing again), at least some of the improvement was also likely due to the amp performing better in balanced mode.

So with newfound confidence that the swamp had been cleared and that my system and the A400s were now speaking the same language, I began throwing a barrage of music at the newly dredged Marsh amp to discover what else lurked beneath the surface.

Sound (AKA Marsh Clearwater Revival)

It is a very good sign when I sit down to do some serious listening and get very little done because my audio system lures me into enjoying the music. Before I know what’s happened, three hours have passed by and I’ve done nothing but feed my musical soul and give my teeth some air. This happened a lot with the A400s in my system. And it wasn’t the bombastic crescendos or gut-wrenching bass that was the culprit; rather, I found it was the little things that really sucked me in. On Oscar Peterson Meets Roy Hargrove and Ralph Moore [Telarc CD-83399], I usually marvel at how well the weight and tone of the heavy ride cymbal are captured, and although that remained with the A400s the cymbal was pushed back and better integrated with the drum set rather than pulled a little more unnaturally forward.

Associated Equipment

Loudspeakers –  Soliloquy 6.2, Thiel CS1.6.

Amplifiers –  McCormack DNA 0.5 Rev. A.

Preamplifiers – Marsh Sound Design MSD-P2000b, Rotel RSP980 preamp/processor.

Digital – Pioneer DV-C302D DVD player (used as transport), Electronic Visionary Systems Millennium DAC 1.

Interconnects – Acoustic Zen Matrix Reference and Silver Reference.

Speaker cables – Acoustic Zen Satori shotgun biwire.

Digital cable – Apogee Wyde Eye coaxial.

And on the Dave Matthews Band's Crash [RCA 07863 66904-2], the acoustic guitar at the beginning of "So Much to Say" not only had the balance of finger, string, and guitar body just right, but the crunch that you feel and hear when in the presence of someone aggressively strumming the instrument was right there with it. While still obviously a function of detail retrieval, it was the way the A400s was able to surface the detail in the complete service and full portrayal of the instruments and the music that set it apart. Likewise, the Marsh amp communicated the slight sheen that I’ve come to associate with Matthews’ vocals, but again it sounded more in balance with and a natural function of his voice rather than an electronic addition to it.

One of the discs that surprised me upon switching to the balanced connection was Mighty Sam McClain’s Give It Up To Love [JVCXR-0012-2], which always sounded like the excellent XRCD recording that it is. But with the balanced setup in particular, I heard a further opening up of the soundstage with an even better sense of image placement both left to right and front to back. Mighty Sam’s trademark vocals sounded very visceral and real, if just a tad less mighty than with my reference amp. Once again, on "Got To Have Your Love" the cymbals floated nicely in space, and I noted the bass sounded full and powerful.

And just to put a little finer point on this bass thing, I pulled out James Taylor’s Hourglass [Columbia CK 67912] and sat patiently (and happily) through "Gaia" until the thunderous drum riff toward the end of the song. There are deep, booming undertones associated with this little trip around the set, and the A400s really flushed out every last one of ’em. But what impressed me even more was that through the thunder I was better able to identify the sound of the sticks hitting the drumheads and the tone of the drums themselves. So the Marsh, in a very apolitical way, seems to have the ability to wield its considerable power without corruption. What also hit me was the background chorus that sounded fuller and more robust -- to the point that I could almost sense as well as hear the layers of singers.

My concerns and criticisms of the A400s were few, one of which, the pairing of the amp with cables and electronics that work with its formidable bass capabilities, I’ve already mentioned. Another would be in the midrange, where, although tonally full and detailed, I thought it sometimes lacked a little force or power. Although Diana Krall and Patricia Barber definitely had that "in the room" presence and feeling through the A400s, they didn’t project that last little ounce of physical energy that can sometimes grab me. Last and least, you may want to take some measurements before introducing this amp to your equipment rack to make sure the rack is up to the task.


While both my reference McCormack DNA-0.5 Rev. A and Marsh A400s are excellent amps, they achieve their excellence through fairly different means. The latter displays a little more oomph down below while going about the rest of its duties with musical integrity and grace, while the former produces less overall bass weight but offers up a slightly more powerful midrange with more pronounced detail. The Marsh’s bass capabilities may be a burden or a blessing depending on your associated equipment and cables, and on that basis I would categorize the A400s as the more fussy of the two in terms of its ability to morph into any system. Despite their differences, I consider both amps to be very transparent in that when listening to either I never got the sense there was anything of significance being added or taken away.

Although it would be a difficult choice given the tradeoffs, if pressed I would probably choose the Marsh A400s for its ability to naturally flesh out tonal textures and its overall balance of detail and musicality.


I won’t go so far as to say the Marsh MSD-A400s is going to cause hoards of tube lovers to convert to solid state, but I will say that the A400s is one of the more refined chip-based amps I’ve heard. It produces tons of natural detail, soundstages and images like a champ, and most importantly captures the life’s essence of the music. It could perhaps use just a little boost in midrange impact, but even with that the A400s is good enough in all other areas that it caused me to reconsider my reference amp.

Put another way, and in deference to my lack of reviewer bravado, the A400s was "different" in a very good way in my system. Needless to say I would strongly encourage you to seek out this high-end powerhouse to hear if it synergizes with you and your system.

...Tim Shea

Marsh Sound Design MSD-A400s Stereo Amplifier
Price: $2295 USD.
Warranty: Two years parts and labor.

Operations Office:
Marsh Sound Design
62 El Camino Dr.
Corte Madera , CA 94925
Phone: (415) 927-4672
Fax: (415) 924-6846

Sales and Marketing Office:
Soliloquy Loudspeaker Corporation
2609 Discovery Drive
Building 105
Raleigh, NC 27616
Phone: (919) 876-7554

Websites: www.solspeak.com, www.marshsounddesign.com

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