Ohm Walsh 5 loudspeaker Page 2

Some manufacturers (Bose, for example) have taken a design path I have dubbed "enhanced stereo," and which some folks might be more inclined to call "artificial stereo." These designs deliberately generate side reflections with the expressed idea of increasing the intensity of the lateral room reflections and thereby enhancing the spaciousness of the reproduced soundstage. I see this as a viable approach, but it must be understood axiomatically that such designs trade off timbrel accuracy for the illusion of a live soundstage. There is no free lunch. You can involve the listening room in the playback and thereby heighten the illusion of real space, but at the same time timbre colorations will result. I think that it is necessary to involve the listening room to some extent to achieve a greater sense of soundstage reality; it would be terrible to listen to two channels reproduced in an anechoic chamber.

Let me give you a concrete example. With the right program material, the Celestion SL600s are capable of generating a highly localized, very specific soundstage, in which instruments are projected with pinpoint accuracy. Yet I have trouble of accepting that soundstage as real, and have a much easier time believing the presentation of the Ohm Walsh 5. I'm sure that John Atkinson and Martin Colloms must be shaking their heads at me by now. I can imagine JA saying, "Well Dick, that's all stereo ever promised; don't be greedy." But, gee whiz John, there must be life after stereo!

The Preliminaries
Program material this time around was almost all analog (my usual front end), apart from a couple of Sony PCM-F1 master tapes. A few CDs were used early on before I optimized the listening room setup, but by the time the dust settled on my listening rooms, my reference CD player had been shipped back to Mike Moffat for a complete overhaul. (Mike is now using the Philips 650 chassis as the basis for his modifications, footnote 1.) The primary amplifier used was the class-A Krell KSA-100, although there were also brief encounters with both the Boulder 500 and Forte Model 1 amps. Interconnects used were: Monster Cable M-1000, Aural Symphonies As One, and the van den Hul Silver. The speaker cable was Bruce Brisson's MIT-750.

Sonic Impressions
The Ohm Walsh 5 started things off in the "dead" end of my dead-end/live-end listening room. No matter where I positioned them in that end of the room, however, their imaging magic was not to be heard. The almost palpable and spacious soundstage I had experienced under show conditions was gone. Instead, the soundstage width was restricted to the solid angle subtended by the edges of the speakers, and the solidity of individual spaces within that soundstage was marginal.

Acting on the suggestion of Don Bouchard at Ohm, I repositioned all of the absorbent material in the room so that the dead end became the live end and vice versa. It worked! The transformation was incredible. The dimensions of the soundstage stretched clear out to the sidewalls with excellent depth. The diffuseness of individual spaces within the soundstage increased somewhat, but each space took on a convincing 3-D quality. The focus within the soundstage was not ultra-tight, being more typical in extent of what you might experience from the back of the concert hall. It might be more accurate to say that the whole end of the room appeared to come alive; I got the distinct impression of peeking into a real space. A very enjoyable experience. One may conclude that the Walsh 5 does need a fair bit of room reflection really to shine, and that the dead-end/live-end arrangement suits it quite well.

In terms of tonal balance, the Walsh 5 is capable of neutral performance. In my listening room, this was achieved with the treble control in the increase position and perspective control in the front position. The bass control was mostly set to the increase position, which is actually the flat setting. Transparency was quite good, especially for a large dynamic loudspeaker, but was not in the class of the good planar speakers such as an Apogee. There was an effortlessness about the sound, however, and the music ebbed and flowed without strain, even on the mightiest of orchestral crescendos. Complex passages were resolved without congestion or audible stress. On New Baby, Don Randi & Quest (Sheffield Lab 12), treble detail such as brushed and struck cymbals was nicely resolved, with natural textures. Overall, the sound quality was very cohesive through the middle octaves. Bass lines, however, were a bit difficult to follow, and there was some loss of pitch definition in the deep bass. Cleo (Cleo Laine: Live at Carnegie Hall, RCA LPL1-5015) was positioned up front as she should be. Resolution of low-level crowd noise was excellent.

The relaxed, effortless presentation of orchestral detail without apparent congestion was very much in evidence on Carmina Burana (EMI ASD 3117). The character of the speaker remained constant from soft to very loud passages. Soloists were localized with an almost palpable body. Sibilants were beautifully elucidated. The transition from the mids to the upper octaves was seamless. The treble was well behaved, without sizzle or zip. The boys' choir was correctly located to the left and back of the stage and did not hover over the left speaker, as sometimes happens. The interplay of the LSO chorus and the boys' choir was nicely resolved. The panpotting of soloists into the soundstage was very obvious.

But a hint of bad news for the first time: there was a slight cupped-hand coloration to soprano voice (Sheila Armstrong). This I had to verify using master tapes of my wife, the soprano. Sure enough, the upper-octave sweetness of Lesley's voice was gone. Her middle registers were darker-sounding and colored by a slight cupped-hand or megaphone-like coloration. Much later, I undertook to determine if this was something inherent in the sound of the Walsh 5 or merely a room artefact. With lots of absorbent material to the sides and rear, the level of this coloration was somewhat improved, but the imaging suffered. A genuine Catch-22 situation. In any event, the coloration never disappeared completely, so I would have to conclude that it is a characteristic of the speakers.

I was sure that a 1/3-octave frequency sweep would reveal an aberrant frequency response, but I was wrong. In fact, from about 500Hz to 20kHz (which was as far as I measured), the Walsh 5 was almost ruler flat when measured on the supertweeter axis. There were the usual dips and peaks in the in-room bass response, and the bass was down 4dB at 25Hz—in complete accord with Ohm's specifications. The source for the coloration remains a mystery, therefore.

An additional coloration manifested itself on West of Oz (Sheffield Lab 15): the lower mids and mid bass were slightly obese and sluggish, with a little extra "oomph" on bass transients. Bass guitar sounded an awful lot like a double bass.

The spaciousness of the recording site on Laudate! (Proprius 7800) was nicely reproduced. The chorus, however, was painted in broad brush strokes, with little fine-structure spatial resolution. As a result, it was difficult to pinpoint individual voices within the chorus.

More serious in nature were the alterations to violin timbre. David Abel's Guarnerius (Wilson Audio Beethoven/Enescu sonatas for violin and piano) lacked the requisite amount of sweetness and focus, being instead grainy and dry. In contrast, on the Quad ESLs, this Guarnerius really sings. A similar fate befell Itzhak Perlman on the Bruch violin concerto (EMI ASD-2926). Itzhak's violin tone was dryish-sounding and lacking in sheen—not good news for lovers of violin sound. Guitar sound on Pedro Aledo: Cantatos Antiguos y Cantatos Nuevos (Pierre Verany PV-12793) lacked speed on attacks, and plucked sounds were simply too rounded. There was also something the matter with Pedro's voice, which took on a slight cupped-hand coloration. Brass sound on Sheffield Lab's The King James Version was a bit too polite and lackluster. The extreme treble was fine, however, and the soundstage was fully emancipated from the confines of the speakers.

Putting the Pieces Together
The Ohm Walsh 5 proved to be a difficult speaker to review. First of all, it is quite room-sensitive, requiring a lot of fine tuning to achieve its full imaging potential. Second, it is a mixed bag of virtues and colorations. I'm very enthusiastic about its strong suits. The lifelike soundstage it can create is very captivating, and it excels in the areas of dynamic range and sheer cohesiveness of musical textures. This is clearly a speaker on the verge of greatness. But to coin a new audio verite: for every audio problem solved, another two are created. I find the midrange colorations of the Ohm Walsh 5 very troublesome. They encroach on the sanctity of two of my favorite instruments: female voice and violin. There are also problems with pitch definition in the deep bass, but the former issues are the major ones to my mind.

So what's a poor boy to do? A clear recommendation is out of the question, but the Ohm Walsh 5 is still definitely a speaker worth auditioning; the soundstage it creates is alone worth the effort. Without those midrange colorations, the Walsh 5 could be a milestone speaker; I hope it continues to evolve in that direction.

Footnote 1: Although we recommended Mike Moffat's modified CD player in "Recommended Components" in Vol.10 No.3, California Audio Labs has pointed out that Mike's contract as a design consultant for them precludes him from selling more than six modified players per month. Regretfully, therefore, we must withdraw our recommendation.—John Atkinson
Ohm Acoustics Corp.
241 Taaffe Place
Brooklyn, NY 11205
(718) 783-1111