The Fifth Element #10

The fundamental object of the invention is to provide...the listener a realistic impression that the intelligence is being communicated to him over two acoustic paths in the same manner as he experiences in listening to everyday acoustic intercourse....—Blumlein, et al, British Patent #394,325, issued June 14, 1933

Rare indeed is the audiophile who has not experienced—at least momentarily—the strong desire to make a high-quality recording of something. Many audiophiles are not only music lovers, but musical amateurs as well, or at least have family members or friends who sing or play an instrument. This month's column is about getting good-sounding recording equipment without breaking the bank.

A state-of-the-art purist-minimalist stereo recording setup for recording music in a natural space costs anywhere from $20,000 to more than $50,000. The equipment I recommend here costs approximately $1500 (not including a CD-R recorder), but it makes recordings that can sound better than many commercially available CDs.

The Denecke AD-20 microphone preamplifier and analog-to-digital converter is contained in a blue metal chassis about the size of a Stephen King paperback. It accepts balanced professional microphone inputs by means of two XLR connectors. Digital output level (or channel balance) is adjusted by two very small knobs.

The AD-20 converts analog to digital at 20 bits/44.1kHz. The AD-20 does not redither the signal—its output is a true 20-bit signal with a noise floor of about -98dB. When a 16-bit DAT deck truncates the last four bits of the 20-bit signal, the noise floor is claimed to act as "natural" dither. The AD-20's S/PDIF output is carried on a 1/8" mini phone jack.

Unlike a Stephen King paperback, the AD-20 is crisply no-nonsense in design and execution. (It also has a belt clip.) The AD-20 provides a clean signal that, to my ears, is noticeably quieter than affordable analog microphone preamplifiers. The most startling feature, though, is the AD-20's price: $325. Given that the AD-20 costs about the same as an entry-level analog microphone preamplifier, it's almost a no-brainer.

The "almost" is because most professional-quality microphones require outside power (carried on the signal cable, in fact) to operate. The AD-20 was designed with ENG (Electronic News Gathering) and other video work as its primary market. Power consumption was a prime consideration, so the AD-20 does not provide "phantom" mike power.

The AD-20's lack of phantom powering is no real obstacle, for two reasons. First, there are a few high-quality microphones that operate on their own internal batteries. Also, Denecke offers a two-channel battery-powered phantom power supply for $150.

Component-sized DAT recorders are better machines, in terms of performance and longevity, than "consumer" portable DAT recorders. They also cost much less than professional-quality portable DAT recorders. Markertek, a broadcast supply house whose catalog is a veritable cornucopia of things you don't yet know you really need, sells the Sony PCM-R300 DAT recorder (list $995) for $649. For about $30, Markertek will make a custom Canare S/PDIF digital cable for you to go from Denecke to DAT with a mini mono phone plug on one end and an RCA plug on the other.

DAT is, as far as I am concerned, the most practical and intuitive approach to affordable live digital recording. Recording live to a computer's hard disk is a long way away from being practical for amateurs, and costs a lot more to get started. (I'd be concerned about disk-access noises, too.) Most CD recorders are kludgy and impractical for live recording. They're good for archiving data but not for capturing it (but see below for new developments). Mini-Disc recorders are even less robust and practical, but do have the advantage of giveaway pricing.

The only drawbacks to using a component-sized DAT deck are its bulk and its need for wall power. In the first instance, I assume that your recording activities will be with the permission of all involved, so setting up your equipment and getting access to a wall socket should not be issues. Be alert that many older buildings have a lot of fluorescent light noise and dimmer hash on their power, and a good power-noise filter (not necessarily the same thing as a surge protector!) may be necessary if your recordings are not to suffer. But, on balance, it's preferable to have to find wall power than to have your portable recorder's batteries run down in the middle of a performance.

If you're recording in a home or a small space, the K&M KM-201A2 microphone stand ($44) will do. If you're recording a chorus or orchestra in an auditorium or church, a photographer's light stand that can get the microphone 12' or so up above floor level, such as the Avenger AVG-A635B, will prove itself worth the $95. Both are available from Markertek.

Keep in mind that you'll usually set up your recording equipment in the same acoustic environment in which you'll be recording. Use closed-back headphones, so you don't get leakage either way. My cheap'n'cheerful recommendation is the Sony MDR-7506 (list $135, Markertek $99), which JA used (along with more expensive sets from Stax and Sennheiser) for location monitoring for Cantus' Let Your Voice Be Heard CD.

Jerry Bruck, chief engineer and owner-CEO of Posthorn Recordings, is the former US importer of Schoeps microphones, and he remains a dealer. Schoeps microphones are a prime choice for professional engineers, but most likely cost too much for most amateur use. However, Schoeps does make the only full-fledged professional-quality condenser microphone that runs on an internal battery: the Schoeps CMBI. Two CMBIs and a stereo mounting bracket cost about $2500. (People are happily using the Denecke AD-20 with Schoeps CMBIs. The Denecke is that good.)

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