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THE MOTIF MC-7 PREAMP: A TRANSISTOR PREAMP THAT BEATS THE PREMIER THREE AT ITS OWN GAME!
Anthony H. Cordesman
Dual-mono preamplifier with separate power supply.
Frequency response: conservatively specified at -0.5/+1.0 dB, 5-100,000 Hz.
RIAA is flat within 0.25 dB, 20-20,000 Hz.
THD and IM: less than 0.1 0 /0 within rated bandwidth.
Gain: high-gain phono stage, 55 dB; low-gain phono stage, 35 dB; line stage, 27 dB. Price: $3500, plus solid wood cabinet ($185-225, for oak or paduk. respectively).
MANUFACTURER: Conrad-Johnson Design, 2817 M Dorr Avenue, Fairfax, VA 22031. (703) 698-8581.
The Motif MC-7 preamp is both easy and difficult to review. It's easy to summarize the Motifs overall sound quality: the MC-7 is a transistor preamplifier with all the virtues of the Conrad-Johnson Premier Three tube preamplifier, and it sonically outperforms the Premier Three in every respect.
The MC-7 is the first transistor preamp to definitively show that transistors can pro duce every sonic merit of the very best tube preamps.
The Motif MC-7 has superb soundstaging and midrange, and excellent dynamics, transparency, and musical detail. It also has a moving-coil gain stage with a superb combination of high gain and low signal-to noise ratio, but with the dynamics and life of the best tube head amps. In short, Bill Conrad and Lew Johnson have made the leap from tube preamp to transistor preamp in one swell foop. They have produced a product that outperforms their best tube preamp, and which competes for the title of world's best.
The Sonic Details: The Best of the CJ Breed
The difficulty in reviewing the Motif lies in explaining what "sonically outperforms the Premier Three in every respect" really means. It does not mean perfect or neutral in the conventional sense of the terms. Like virtually every top high-end designer or design team, Conrad-Johnson designs have a consistent sound character. CJ products are not "neutral," if this means sounding like most other equipment. You buy CJ equipment because Conrad and Johnson have set unique design goals, and you agree with the sonic result.
The frequency response of all top-of-the line CJ equipment has had this consistent character for at least the last five years: very powerful and extended bass, and a warm upper bass to lower midrange; flat mid range and upper midrange; a lower treble sweet and lacking hardness, which suffers slightly in terms of "life," without a sacrifice of detail; and mid-treble and upper treble that sound rolled-off in comparison with most other electronics, but which have the upper-energy response found in most live performance.
The Motif MC-7 has all these sound characteristics, with the added advantage of a more elevated and slightly more natural portrayal of upper-octave timbre than previous CJ preamps. At the same time, the Motif retains CJ's outstanding soundstage depth, but provides more openness, with extended width and height.
The q sound has always been characterized by detailed imaging and, within the overall soundstage, an exceptionally natural and stable spread of instruments and voices from left to right. The Motif, however, ex cels any previous CJ design in its ability to fix a given performer or instrument in terms of depth as well as in left-to-right placement; in previous CJ preamps, the excellent illusion of "depth" has not been as easy to relate to a given instrument. At the same time, though, the MC-7 does not have the natural holographic depth of the Audio Research SP-10, a result, I think, of its slightly soft upper octaves, and, more importantly, of its transient dynamics.
The transparency of CJ equipment has always been good, but better at mid to high sound levels than at low levels; low-level musical detail has always been slightly masked. The same has been true of dynamics: very live and quick once the sound level rises above the quiet passages, but a little "dead" in the soft passages. The Motif is still just slightly lacking in transparency and dynamic life in soft passages, but is significantly superior to the Premier Three. It now competes with the top tube or transistor preamps of many other manufacturers in this respect; the Premier Three did not.
The Motif MC-7 also retains the traditional tendency of CJ equipment to create the illusion of sitting mid-hall, rather than front row. The MC-7 again outperforms the Premier Three, or any previous CJ preamp, in making this seating position seem realistic. There are many small musical details--hall noise, percussion transients, bowing noises, etc.--which come through during phono playback using the MC-7 that are blurred or even missing with the Premier Three. These details also come through in a musically natural way. In fact, the more you listen to the Motif, the more you notice additional clues about a recording's location, milting techniques, and mix-down practices.
If you loved (or merely liked) CJ equipment before, you'll love the Motif MC-7 even more. It is not, however, an attempt at "convergence." If you preferred another brand of "designer sound" -more energy in the highs, a more forward sound, etc. - you simply will not get them. The MC-7 is a no-holds-barred to provide the sound that its designers feel is musically right; if you feel that a Porsche should be a Rolls Royce, the Motif is not for you. At the same time, if you want to recreate a classic con cert hall sound that can extract musically natural pleasure from a wide range of recorded music, you will find it very difficult to do better.
You will, of course, need to keep the rest of your equipment consistent with the strengths and balance of the Motif to get the best performance. Mixing the best red with the best white wines does not result in the best character from both (it only produces Sea Cliff Rose, and you all know about the problems in the lower east side of New York State wines!). You need a very live and dynamic cartridge, such as the Argent Diamond. You need very powerful tube amplifiers: the Conrad-Johnson Premier Fives, Audio Research M-100s or D250-II Servo, or any of the few powerful transistor amplifiers that are open but without a hint of hardness or upper-midrange glare (the newer high powered Krells and the PS Audio 200C are good cases in point 1 ). You need a very quick speaker with extended frequency response: the Thiel CS2 or CS3, the Infinity RS-1B or RS-2B, the larger Vandersteens, the Martin Logan, the Apogee Duetta, and Quad ESL-63
[1. As are the Threshold SA-1 and Rowland III (latest version) mono amplifiers. –JGH]
are all good examples (but remember the Apogee and Quad ESL-63s will need suitable amplifiers). The Problem of Human Engineering The Motif MC-7 isn't Everyman's product in other ways. Its features, styling, and "ergonomics" make few sacrifices to user convenience. The good news is that the MC-7 offers the convenience of a superb high-gain stage, one that should be suitable for virtually all moving-coil cartridges, and that is free of the aging and other problems associated with tubes.
The bad news is that the MC-7 is so much a purist design that any features that would interfere with sound have been omitted.
Phono gain is switched from the back, and the moving-coil loading is affected by the fact the unit performs best with an "intermediate" cartridge load of about 2000 ohms. You get only one phono input, one conventional line stage input, and switching for one tape recorder or other line stage input.
The dual-mono design might as well be dual-chassis: each input is switched separately (allowing "stereo" from different sources); there is no balance control-there are dual volume controls (lacking any dial or reference calibration for styling considerations), and they vary the gain in an awkward logarithmic manner so that even slight discrepancies in adjustment give one channel much more gain than the other at the low settings at which they are most likely to be used. This is particularly infuriating; the extraordinary resolution of the Motif MC-7 means you are likely to bounce up and reset the balance for every record, CD, or tape so that the soundstage "locks in" and the overall musical image "floats" precisely in the center.
CJ does plan to sell a separate high-level switching box for the Motif, but this will only allow you to increase the amount of equipment you use. It doesn't deal with the human engineering problems of dual, logarithmic volume controls, and you still have to face the fact that differences in phono and line stage gain with the MC-7, or the odd twitch of a volume control, can produce enough "blast" to drive an IRS woofer column into orbit.
The Motif MC-7 is a preamp for someone who listens primarily to records, and who keeps her or his system relatively stable so that the associated components fully exploit the potential of the MC-7, and its full range mid-hall sound. It's a ne plus ultra preamp for someone who appreciates Con rad and Johnson's sonic taste and design goals, and who will buy and retain an over all mix of components that fully achieve them. The MC-7 is a preamp for someone with a large record collection whose primary criterion has been to get the best possible musical performances, rather than audiophile oddities with exaggerated upper octave energy, unnatural transient detail, or a sonic perspective miked from the conductor's armpit. The Motif is a musically natural unit, not one with an exciting electronic character of its own.
Tube Or Not To Be
In closing, I am conscious that I've dodged the particular technologies used in the Motif MC-7, and the issue of tube versus transistor. I suspect, however, that both issues are moot compared to the importance of understanding the MC-7 as a new con tender for the world's best preamp because of the designers' ability to translate their sonic taste into practice-regardless of which technology they choose to work in.
It is an aspect of the MC-7 you should listen for in making your purchasing decision.
The fact that Conrad-Johnson now give you the added gain and reliability of transistors is a very real advantage, but it is the sound that counts.
You should also be aware that a less ex pensive Motif preamp ($2200) should be on the market just about the time you read this, and will have many of the switching and control features missing in the MC-7. The new "bargain" Motif will not provide the state-of-the-art phono reproduction of the MC-7, but, in the face of financial crisis, I'd recommend that you delay pawning your children to buy the MC-7 until you give the cheaper version a listen. I don't normally lecture readers on religion, but certain passages of the Old Testament hint that even high-end audiophiles should hesitate before sacrificing their firstborn to the god of audio.
--
[based on a Feb. 1986, Stereophile review article]
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