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Positive Feedback ISSUE 55
SPA-4C Phono Stage - The Hi-Fi Antedote
as reviewed by Marshall Nack
Sometimes you can tell a book by its cover. There is a white LED in the center of the faceplate of the Concert Fidelity SPA-4C Phono Preamp, towards the top. This is the On indicator. It is a dim pinpoint; at first I didn't even notice it. The entire chassis is like that, so understated as to hardly be noticed. No radiant displays, no glowing knobs, no color—just an unbroken expanse of matte silver.
It occurred to me: if one were seeking an analogy for the SPA-4C's sound, that visual of the chassis would suit just fine.
Certainly, my reference ASR Basis Exclusive phono stage makes splendid music—there's no doubt about that. Listening to the Schutz Madrigaux Italiens, a wonderful, late harmonia mundi LP from 1985 (HMC 1162), I find very little to quibble over. This LP is an example of the noted skills of HM's lead engineer, Jean-François Pontefract. (Any LP credited to him is worthy of your consideration.) Through my reference front-end, perhaps the sopranos are a bit dark, their images a bit too fleshy. The same can be said for the accompanying theorbo. Perhaps timbres are also a bit thick. Perhaps this presentation is not the utmost in refinement. But these are relatively minor quibbles: In the overall scheme of things, the ASR gets it mightily correct.
Now let's swap over to the CF. The sonic landscape shifts radically. On the conventional audio scorecard, speed, dynamics and weight slip from the pace-setting ASR. The CF won't command your attention with its immediacy. I can readily imagine many died-in-the-wool audiophiles—those who ascribe to the standard criteria promoted by the audio press—are gonna have issues.
But hold on, because in spite of that slippage, the CF managed to render a simulacrum that grabbed and held fast my attention. Something else is going on. All of the minor quibbles vanish. Image sizing has been corrected, both in relation to each other and across the stage; body is anatomically appropriate; voices have more natural tone; timbre is amazingly refined. The CF has scaled the barriers hampering the credibility of the illusion and ratcheted up its potency. It is capable of taking you on the proverbial magic carpet ride. The scorecard represents Hi-Fi—the CF is adamantly not Hi-Fi.
Let me qualify the magic carpet transport. Usually, when we use this metaphor it refers to a presentation that lifts you out of your actual physical environment and places you in some wholly different perceptual, acoustic space. Usually, this new place is warm and intimate—and a complete fabrication! You don't go on voyages with the CF: You stay put in your room.
I have a first pressing of the Arthur Rubinstein Rhapsody on a Theme of Paganini, an old, justly famous, Golden Era recording (RCA LSC-2430). The LP is known for its remarkable fidelity and soundstaging. The solo piano—the entire piano and all of its keys—images dead center, a little forward and a little too prominent. (That's the way they miked soloists in 1962. They still do.) First violins are far left, cellos right. When the first violin section comes in, the image broadens beautifully. Whether it's a solo instrument or the entire string section, the CF scales the image proportionally to the number of instruments playing.
Image locations are spot on; however, there is not much in the way of isolation. You won't find hard-edged boundaries. It occurred to me the way the CF does soundstaging is analogous to how we talk about speakers that are integrated. With some speakers, different frequency bands are heard in isolation. With others, they are integrated. Well, the CF stage is integrated in that fashion—it is holistic. (Argh, I didn't want to use that much-abused adjective, but it does fit.) And we all know which way is closer to how it happens in real life, right?
Reality vs. Hi-Fi
Along with its uncommonly credible soundstage is a beautifully crafted timbre. There is neither too much in the way of overtones nor too little. The CF also has a lithe, fluid musical line. Some components sound rigid; this one sounds free and unconstricted. These three elements—imaging, timbre, and dynamics—give the sound the natural flow of liquid H20.
This is the CFs forté. When you think about it, this also describes live, unamplified sound pretty well. I can readily believe a vocal quartet would sound the way it does through the CF, especially if performed unamplified (check) in an old chateau (check) and recorded by an excellent engineer (check). Under these circumstances, the CF puts me into that lofty state where I can suspend disbelief.
The Audio Note Japan M-77 Preamp
These ruminations triggered memories of the happy time I spent with the Audio Note Japan M-77 preamp a couple of years ago. That component set the high-water mark for this kind of credibility. There are common elements in their voicings. In both units, the tonal balance is slightly elevated, centered a little high in the midrange. (The M-77 is a bit lighter than the CF. The ASR is considerably darker.) The treble is sweet and rolled off—there are no jagged edges anywhere. The bottom is tight, but not particularly fulsome, extended or aggressive. Neither component plumbs the nether regions to the extreme or with the force of the ASR. The midrange is well developed, extremely fluid and nimble, but not lush or overly warm. Inner life is outstanding. Macro dynamics are about average. And the presentation is grainless, wide-open and laid back. I've come to associate this signature with six-nines-purity silver, specifically the way the Japanese use that metal.
"This LP is light and has transparency in spades," was the comment from the panel regarding the Rachmaninoff Rhapsody on a Theme of Paganini. But then, when I put on an English Decca of Britten's Variations on a Theme of Thomas Tallis, the same panel thought, "This LP is dark." The varying reactions are a good sign 'cause it tells me that, while I can't call the CF neutral, it is passing a good deal of what's on the LP. I was readily able to hear differences in recordings.
Tube Sound without the Valves
I figured the CF would do well with vintage Blue Note LPs, given its midrange dominance and tubey voicing. And how! On a vintage mono New Soil LP with Jackie McLean (Blue Note 4013, a 47 West 63rd st. pressing), listen to the way his horn floats in front of the rhythm section, big, fat and lithesome.
This is what jazz aficionados want to hear. While they'd be using tube gear to listen to mono LPs, this is what you heard through the solid-state CF. It seemed there would be no gains to having the stereo version—there may even be detractions.
The bottom line is there is no doubt the ASR is comparatively coarse. It gets excellent grades, but timbre and tone are simplified and it doesn't allow me to suspend disbelief.
ASR Basis Exclusive (2008 model)
Yet, while I can do that with the CF, I could not live with it exclusively. First of all, I want those high grades on the scorecard. Secondly, and more importantly, the CF's variety of realism has to be what you are looking for.
Real sound comes in many guises. The CF's particular specialty is like sitting at a distance, towards the rear of the hall. Many audiophiles will find it flat or dull and prefer to ante up for twelfth row orchestra seats for a more immediate and awe-inspiring sound.
Also, this is not what an amplified performance sounds like. As soon as you introduce electronic embellishment, the sound's characteristics change. It becomes more like the scorecard. The continuousness, the musical flow, shrinks up. To an extent, this reflects the devices employed. I know recordings labeled AAD sound better. What if you combined that with tubes in the amplifying / recording process instead of solid-state devices?
Now, if I could only marry the CF naturalism with the darker, saturated tone, the weight, the terrific macro dynamics of the more robust ASR. This would be my ideal and what I would want in a phono stage. Actually, that's my ideal for any component.
The Output Buffer
If you wanted to, you can make the CF sound more conventional.
On the rear of the chassis are two vernier dials that control the Output Buffer. This is a secondary gain stage, designed to supplement the primary MC amplifier. If you need more gain, the Output Buffer can add up to 6 dB on top of whatever the MC amplifier is set to. I had no need to fiddle with it as the MC amp was more than sufficient for my cartridges, but I was advised by the importer to try it because "some people like it better that way."
With the Output Buffer fully engaged, the holistic stage—indeed, all the holistic effects—I described above goes away. On the Schutz Madrigaux Italiens recording, you can discern that the singers are arrayed in a semi-circle because the voices in the middle seem further away and those on the sides are forward, near the speakers. It is more focused with smaller images, more separation and more 3-D effects going on. Their boundaries firm up. And it is less natural sounding.
The Output Buffer makes the CF sound more conventional, more like other gear. The magic carpet has been grounded and is no longer taking passengers.
Design and Function
The User Manual contains insights into the designer's mindset. Masataka Tsuda, the chief designer at Concert Fidelity, has "a perfectionist drive to pursue the limits of circuit simplification and purity." That drive is evident in the SPA-4C, which the manual posits, "… may have the fewest number of elements in the audio signal path among all of today's solid-state phono stages."
Look inside the CF. The vacancy is enough to make you wonder. If you were to equate number of parts to the expense of the component, the CF would raise a lot of eyebrows.
Inside view from front
Inside view from rear
Maybe comparing the cost of each of those parts to the MSRP might tell a different story. At the heart of the circuit are NOS Japanese J-FETs dating from the 1970's. The limited availability of these vintage J-FETs translates to a strictly limited SPA-4C production run of 40 units. Better grab yours now, before they're history.
A separate email from the importer elaborated on the designer's philosophy. In Masataka's own words: "The construction of the active and passive parts making up the amplifying circuit should be as simple as possible….There is no way that an audio circuit…can improve a signal in the course of amplifying that signal."
Maybe this ultra purist approach is what explains why the CF reminded me of passive preamps. It is radical in its simplicity.
I couldn't help but contrast this with a company driven by the exact opposite design approach—Soulution, the Swiss audio company.
Inside the Soulution 720 preamp
Look inside any Soulution component and you also have to wonder: How did they manage to cram in all those parts? The chassis is stuffed to the gills and the signal path is not left untampered with. But they achieve spectacular results and an undisputed realism, albeit one very different from the CF. Obviously there are many ways to approach circuit design.
The MC amp gain and cartridge loading on the CF are adjusted via internal DIP switches. As mentioned, additional gain is available via the Output Buffer gain stage. There were more than enough gain and loading options for my needs, although they are not as ample as usually encountered at this price point.
The CF has one set of RCA inputs and outputs. It benefits from power conditioning.
I used the CF with the VYGER Baltic M and a Dr. Feickert Blackbird turntable.
VYGER Baltic M
Dr. Feickert Blackbird
Cartridges were the Shelter Harmony and Shelter 501 Mk. II. Normally I set the loading for these cartridges to 100 ohms. However, because of the way the CF is designed, I found 30 ohm loading sounded better. Don't presume results based on your experience with other phono stages, because the CF doesn't follow the pattern. Refer to the manual for recommendations and make sure to experiment with several settings.
I had pursued Concert Fidelity ever since I heard them at the Stereophile HE 2007 show, because their room stood apart—everything else sounded like Hi-Fi, to one degree or another. Finally, I have in one of their components for review, their latest phono preamp, the SPA-4C.
Here's a phono stage that is capable of the highest levels of realism. I can relate what I'm hearing to live concert performances. And when I settle in for an evening with the CF, I do not question its truthfulness.
But it is a certain flavor of realism. If you are familiar with the sound of Audio Note Japan you will know what I mean. Then throw in some of the attributes of passive preamps. It is totally un-hyped and uninflected, yet sounds complete.
However, dyed-in-the-wool audiophiles are likely to have issues. On the audio report card grades slip a notch from my pace-setting ASR Basis Exclusive. On the other hand, the ASR doesn't have anything near the realism of the CF.
Audition before purchase is strongly recommended. Marshall Nack
Concert Fidelity SPA-4C Phono Preamp