Mark Levinson ML-7A preamplifier
Mark Levinson was a pioneer of sorts in high-end audio. Around the turn of the 1970s, he flouted conventional wisdom by introducing a line of no-holds-barred audio products priced beyond the means of any sane individual, then proceeded to sell lots of them. Thus did Mr. Levinson prove, singlehandedly, that (1) it is impossible to price a component out of the market as long as it offers at least the appearance of commensurate quality (footnote 1), and (2) there are perhaps more insane audiophiles than anyone had hitherto dared imagine. Today, ML's $6320 flagship ML-6A preamp is only the second-most-expensive model available (footnote 2), and half a dozen others cost more than the ML's "second-string" ML-7A. Only a spoilsport would now contend that $4595 is a "ridiculous" price to pay for a preamplifier.
So, whaddaya get for your money? Without going into tedious detail, suffice it to say that you get the best sound MLAS (Madrigal) knows how to produce, along with construction worthy of a US Navy solid-state laser-activated can opener, and parts which should virtually ensure that the preamp will last longer than its owner. In fact, all MLAS products come with a five-year original-owner warranty, which should tell you something.
They also come equipped with so-called Camac connectors. You're not familiar with Camac connectors? Let me tell you all about them. These are the signal connectors we might all be using today if RCA hadn't had so much clout in the consumer market back in the early '50s, when the audiophile still had a choice between LPs and 7-inch 45-rpm discs. Camacs are small, tubular (in the literal, not the Valley girl, sense), gold-plated, Teflon-insulated, and suitable for instrumentation applications. They make an incredibly positive contact (you can rock a phono input in its socket without getting so much as a click!), and they lock in place. To remove them, you pull back on a sliding outer sleeve, which first breaks the Hot contact, then releases the plug. This means you can pull out a phono plug while the system is on and turned up, without producing so much as a Blap. In short, they are incredible!
Unfortunately, they resemble the all-pervasive RCA plug about as much as Karen Allen resembles Godzilla. They are not compatible. Which means Mark Levinson products cannot be connected to the products of any other company without the addition of special adaptors or custom-wired interconnects with RCAs at one end and Camacs at the other.
This is absurd. I don't care how good Camac plugs are; the simple fact remains that RCA connectors are the industry standard for all consumer-electronics signal interconnections. No amount of proselytizing on the part of M-L for something better will change that. Even if one goes with Mark Levinson components "all the way"which is to say, with their amp and preampyou'll still need those adaptors or the custom interconnects for your phono unit, tuner, CD player, tape equipment, and so on. The fitting of Camacs on all M-L products is tantamount to an American firm fitting kitchen appliances with round-pin European AC plugs because they're "better" than the domestic variety.
M-L makes three phono preamplifier boards for the ML-7A, designated the L-2, L-3, and L-3A. The L-2 board, for moving-magnet cartridges and high-output MCs, provides switchable input impedances of 50k ohms (MM) and 850 ohms (MC), with a second switch selecting 38 or 44dB of gain. There is also provision for adding lower-value loading resistors and/or capacitors, for those cartridges which need either or both. The L-3 and L-3A boards are for MC cartridges only, and offer (respectively) 67 and 55dB of fixed gain. There are no switching provisions on either L-3 board.
Board replacement is easy, if you have the right-sized Allen wrench on hand for removing the preamp's top panel screws. (No wrench came with my ML-7A, but I would presume that one is normally supplied.) Each board is fastened down by a pair of knurled-head screws; replacement merely involves removing the four screws, unplugging the old boards, and plugging in the new ones. Normally, when you buy the preamp, you specify the cartridge you will be using (footnote 3), and the preamp is supplied with the proper boards for your cartridge. Board replacement is necessary only if you subsequently change to a significantly different cartridge.
I was gratified to see a Mono/Stereo switch on the ML-7A. Many perfectionist designers seem to feel that acknowledging the existence of mono sources somehow debases the image of a preamp. Even if you never play a mono disc, the A+B mono facility is useful for trouble-shooting.
Footnote 1: And maybe more than just the appearanceJohn Atkinson
Footnote 2: According to the listings in Audio's 1985 Equipment Directory, only the Krell KRS-1A costs more, at a wildly exuberant $7200! That is a little less than half of what I paid for my 1984 VW camper!J. Gordon Holt
Footnote 3: Can you predict what cartridge you'll be using a month from now? I certainly can't.J. Gordon Holt (That, JGH, is because you are an audio guruJohn Atkinson) (But it should also be pointed out that JGH has been using the MC-2000 as his reference for the last year and a half. He does, of course, test many other cartridges.)Larry Archibald