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Sound Views -- Opinion and comment on the changing audio scene, What's causing the storm over CBS's new CX dynamic-range expansion system. by Robert Long CX: Pride and Prejudice THAT THE ENGINEERS AT CBS are proud of their CX system for dynamic range expansion in LP recordings goes without saying. I suppose it also goes without saying that, just as pride leads to positive prejudice, so sour grapes beget negative prejudice--an unwillingness to recognize virtue fully as intransigent as a doting parent's unwillingness to see fault. Objectivity is a rare commodity when innovation is on the move. The virtues are considerable here. CX is the only proposed system I know of that would stretch the dynamic range of a conventional LP until it ranks with that of digital recordings (give or take a few dB) and do so without requiring dealers to stock two versions: stretched and unstretched. It could make totally unnecessary the sort of dynamic manipulation (all forms of compression, from manual "gain riding" to peak limiting) that now disfigures virtually every mass-market disc you can buy, whether you're aware of the disfigurement or not. Arguably, it also would make unnecessary the much grosser compression that is a way of life among broadcasters--though, being a way of life, its abandonment seems unlikely in the predictable future. But since you may not have seen the "High Fidelity News" column in our July issue, perhaps I should recap the operating principle involved. The sound still is compressed in making the CX disc master, but according to a formula that has been carefully arrived at to avoid the more invidious manifestations of compression or compansion. Thus the record can be played on conventional equipment and should sound no worse than the run-of-the-mill contemporary product. But because the compression follows a specific program, it is reversible if you have the matching expander. That's how the CX system can recover the dynamic range of the original master tape, which conventional discs can't do. Nothing comes "free," of course, and there are some negative points to be considered. Since the compression is foreordained, there is less opportunity for sonic sleight-of-hand. With manual gain riding, for example. an expert can get more compression with less audibility than any programmed circuit can be expected to manage. Some engineers (including Angel's, unless my ears deceive me) compress vocal tracks more than the accompaniment to keep the text and melodic line from being swamped. Telling an engineer he can't use these special tricks, which have helped build his career, is like telling a Tetrazzini that the opera-house management doesn't like high notes. You can't expect a demure smile in return. Then there's the predictability of the results. Many of the studios I've been through (at least among the ones doing pop or advertising work) have rinky-tink speakers sitting in a corner of the control room so the producer or account executive can judge what the recording will sound like "at home." In theory, the sound should be at least acceptable heard on the inferior speakers and excellent when the studio monitors are switched back in. But meeting such disparate goals often involves compromises, and now CX will add two more variables-with and without decoding and therefore require more listening, time, tradeoffs, and money: It's not an encouraging list for a conscientious and budget-conscious producer. And what about the mastering engineer? The "body English" that he's been applying-which, in the pop field, is sometimes considered the secret ingredient that creates hits-will also have to be evaluated two ways. In theory--and, I suppose, in practice-he's making up for the expected losses that would otherwise occur in the mastering and pressing chain, and thus he's preserving what the producer created. If he no longer knows just what the end product will sound like, depending on whether the listener does or doesn't own a decoder, how can he continue to call the shots? Again, his career could he at stake. Further muddying the waters is CBS itself. In a press release announcing that RCA had signed a CX license, CBS says: "CX encoded records can be played on conventional stereo equipment and will sound the same as standard records." Now that's just asking for an argument. "Will sound the same?" Not exactly, even in CBS's own theory. "Standard records?" What is standard? If CBS goes back to its original tapes of Boulez and the New York Philharmonic, remixes them (without any compression) for CX, encodes them, and re-masters, the results should not sound the same as the "standard" product now on the market-much less like DG's "standard" with Karajan and the Berlin Philharmonic playing the same music. But I'm theorizing on the basis of what should happen with classical recordings. What does happen on the only CX masterings--all pop--I've been able to listen to at my leisure so far is not worth fussing about in terms of the arguments we've been examining. Any expander--including the CX decoder--exaggerates level differences: where there are none to speak of it has nothing to exaggerate. There simply isn't enough dynamic range in this pop program material to make the decoded playback significantly different from the undecoded playback most of the time. The lead-in grooves and the spirals between numbers are another story, of course. Without decoding, they contain the usual collection of noises, almost--all of which disappear when the decoder is switched in. That demonstrates what's at stake: a really dramatic improvement in dynamic range for recordings produced to make use of it-which the pop pressings are not. But there's a much bigger message here: Give CX a chance! Everybody seems to be choosing up sides like kids at a pickup baseball game. That's what happened with quadriphonics, which eventually became a dirty word in the audio industry because everybody got kicked in the shins in the subsequent in fighting between systems. Not that CX is another quad: With companies responsible for an estimated half of the country's annual new recordings already signed up for CX, there's already more of a consensus than there ever was on any quad system. But let's not lose our heads in either direction. We've got to do a lot more listening: you, producers, engineers, musicians, journalists and critics everybody. Only then will a consensus on CX, if it emerges, mean anything. -HF ---- Backbeat -- Pop-Pourri by Sam Sutherland: Will CBS's new dynamic-range expansion system save the record industry? Trends to watch in the music industry. Will CX Be an RX for the Record Industry?THE CX COMPANSION disc (see story above), unveiled by CBS Technology Center late last year, makes an impressive promise that would be welcome in deed if kept: By means of low cost add on technology, it would sidestep much of the extraneous noise incurred by the limitations of mass disc manufacturing and poor pressing compound. With consumer digital audio still years away from the broader marketplace, CX offers an attractive interim solution to the current gap between hardware and software audio capabilities. The principle behind CX-compressing the signal during the first stage of processing and then expanding it electronically during playback by means of a decoder-isn't new. What is new is its alleged universal compatibility: Its proprietors say their discs will sound fine when played back without a decoder (which probably will cost between $50 and $100). With the discs selling at the same price as conventional stereo al bums, and, decoded, boasting some 20 decibels of added dynamic range over regular records (bringing them within 10 dB of that claimed for digital systems), it's no wonder that the prospect of CX seems so attractive to record manufacturers continuing to face a soft market. Warner Communications and RCA have both agreed to encode their LPs for CX, sewing up a potential market share of at least 60% even without commitments from other labels. With that preordained clout, the CX disc has to be a shoo-in, right? Hardly. As quick as its acceptance by major soft ware manufacturers has been, the actual use of the system on new releases re mains contingent on the blessings of major artists and producers. Although CBS and Warner jointly issued a statement promising adoption of the system, Warner later qualified its stance by stating that an act must give its consent to have its tapes encoded prior to disc mastering. Thus far, there are only thirteen CX encoded discs commercially avail able, all from CBS labels. The earliest-and most vocal-reaction to CX has come from professional disc -cutters, whose outcry at pressure to install encoders in their mastering facilities first broke in Billboard (June 27, 1981). Major mastering engineers such as Doug Sax, Bob Ludwig, and Ken Perry-representing such well-known shops as the Mastering Lab, Masterdisk, and Capitol respectively-termed CX's effect on program "a disaster and not compatible" (Sax), "a pain in the butt" (Perry), and, in the case of Murray Allen, president of the Society of Professional Audio Recording Studios (SPARS), "a step backward." The engineers claimed... ---- The blessings of artists, producers, and engineers are vital for success. ---- ...that CX discs played back without a de coder do, in fact, reveal audible problems, primarily in a compressed dynamic range and imbalances between low and high frequencies. And Sterling Sound's Lee Hulko said that calibration of the decoder by consumers will also pose problems. Apart from CBS's defense that the system hasn't had sufficient time to be accurately assessed, the irony in all this is that the first crop of new CX recordings doesn't give would-be critics a solid basis for comparison anyway: Most of the artists involved are unknowns, and most are involved with highly amplified music. Contemporary pop and rock long ago sacrificed dynamic range and purity of signal processing to the pressures of competition for airplay: With typical platinum contenders containing a host of intentional signal distortions and al ready compressed for maximum clout over tiny radio speakers, the effect of CX-decoded or no-is practically sub-liminal. Only on relatively uncompressed, untreated programs. such as acoustic jazz and classical recordings, can CX's effect be judged properly. Yet it is the pop clout of these engineers--many of them recognized masters, to be sure, but also influential because of their record chart statistics and their pop -oriented clients--that gives their umbrage significance. That they have a vested interest must also be recognized. Sax, one of the most vocal opponents and a long-term advocate of such audiophile alternatives as direct-to-disc, reveals his bias in the statement that the analog disc "with all its faults has always allowed the best musical efforts of producers, engineers, and artists to appear on disc. CX now breaks the chain." In other words, it sidesteps much of the cutting engineer's control over the final sound quality. Still, it's hard to blame them for their cynicism, given such costly past furors as the Four Channel Wars, the lightweight Dynaflex disc, and "enhanced" stereo from mono. Perhaps even more immediate is the issue of CX's acceptance by hardware interests. CBS claims that its circuitry, when reduced to a simple inexpensive module, could be incorporated in future amplifiers and receivers and engaged with a front-panel switch, adding on only about $5 to the end cost. Yet thus far only five conspicuously small companies have taken licenses to manufacture the outboard decoder: Phase Linear, Sound Concepts, Audio Inter national, Audionics, and MXR. Chari table observers could simply attribute the electronic giants' lack of interest in CX to traditional Japanese caution in new format commitments, or perhaps corporate rivalry is behind their reticence. In any case, until a firm of the magnitude of Pioneer, Technics, or Yamaha adopts the system, CX is hardly at first base. Whether or not the Japanese majors (who remain silent) view the sys tem as an obstacle to marketing true consumer digital audio, it's not out of line to wonder whether their first exposure to CX raised questions about its efficacy. All of this leaves the consumer very much in the middle for the foreseeable future. CBS's contention that the system hasn't been given enough of a test is worth noting, as is the promise of a process that would add 20 dB of added head room to conventionally priced LPs. Pressed on the new generations of domestic pressing compound such as Quiex or Keysor Corporation's newly-developed quieter vinyl (see "High Fidelity News," ), CX might be a bridge to the digital era, not a barrier. Yet past experience doesn't really encourage those expectations, nor does the music industry's current dilemma of soft sales and spiraling costs. In a mass-merchandising trade where volume is the top priority, there is a very real threat that CX would be used as a panacea for all common problems of record production. It won't solve groove wear, and no matter how cheaply the circuitry is built, it can't heal a record scarred in pressing or un-playably warped in transit. The audiophile LP trade underscores this issue with the success of remastered pop material that, in many cases, benefits as much from extra care in pressing and handling as it does from esoteric cutting techniques. It has already been theorized in some quarters that a high-powered CX campaign might scuttle the new premium-disc trade; how CBS juggles its own Mastersound audiophile products with its CX venture should be a revealing barometer. -HF ---- Also see: The Autophile, by Robert Angus--Two developments foretell profound improvement in stereo FM reception
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