Aug 21, 2019

On Sure Things…

By Bryan Geyer

When it comes to creating or upgrading a modern audio system, these are my ten general “good sense guidelines.” I apply them with confident certainty, and I recommend them without reservation.


(1) That solid-state class A (and pseudo class A) high-bias power amplifier design is extremely inefficient, and that such amplifiers run w-a-y too hot to be tolerable. In addition, those amplifiers commonly weigh ~ 100 pounds, a mass that’s grossly inconsistent with home decor and display. Instead, stick with solid-state class A/B bias, or the best of the new class D power amp. designs. For admirable excellence at a practical price ($1,495 list), consider Parasound’s recently upgraded model Halo A23+, http://www.parasound.com/a23+.php. It’s a well designed type A/B powerhouse (160 watts per channel into 8Ω, both channels driven) in a package that’s 17 1/4” wide by 15 1/4” deep, and weighs 27 pounds. This product will fit nicely on a 16” deep wall-mounted shelf if you use a replacement power cord (AWG 14, type SJT, fully molded) with a 90˚ angled C13 socket (refer http://www.stayonline.com/molded-cord-configurator.aspx). Also use right-angled RCA adapters, available at https://www.parts-express.com/gold-rca-right-angle-adapter-long--091-184.

(2) That a vacuum tube power amplifier bears consideration only if you intend to recreate a 1950s-’60s vintage replica, and knowingly accept all of the penalties that ensue when compared to a solid-state equivalent. Expect elevated hum+noise, 15X-to-40X more THD, a 8X-to-10X increase in output impedance, grossly inefficient operation, lots of heat, incessant bias drift, infrequent but inevitable failures, and periodic high expense to replace matched sets of archaic output tubes that are produced solely by obscure sources in China, Russia, and Slovakia.

(3) That an active analog crossover network is technically superior to a conventional passive crossover network in every vital respect: Initial accuracy, slope accuracy, long term stability, response flexibility, and operating convenience. Further, an external active analog 4th order crossover is essential if you expect to use subwoofers in your setup (refer “Tech Talk”, sidebar). Consider the Marchand XM66 active crossover that I currently use; https://www.marchandelec.com/xm66.html.

(4) That fully-sealed self-powered subwoofers (minimum = 2, but more are welcome if your space and decor permit) will improve the acoustic performance of any system, in any listening room that’s smaller than a public auditorium, regardless of the quality of the main speakers in use. Of course, all subs need to be optimally adjusted with respect to input gain and phase delay, but that’s easy to accomplish—with full visual assurance (see “Tech Talk”)—if you utilize some basic instrumentation.

(5) That a fine audio system should be located in the primary living room. It’s likely the largest enclosed space available—probably has the least number of fully-paired parallel surfaces—and it might have a higher ceiling. Do recognize that displaying your power amplifiers as a “techno-heap” in the middle of one end of that room is messy, obsessive, and selfish. (Also entirely unnecessary unless you own monstrous 50-100 lb. power amps.) Instead, use sturdy wall-mounted shelves, such as those sold by https://www.containerstore.com/s/elfa/components/elfa-solid-shelving/123, or buy some attractive contemporary audio furniture to house your electronic baggage. A giant mound of hi-end tech may seem gorgeous to audiophiles, but it looks like pawned overstock to others.

(6) That acoustic excellence can be achieved without resorting to massive loudspeakers, and that enjoyable listening rooms should never look like the photo that’s on this page.

(7) That classical music will become a vital source of great personal pleasure if you start by acquiring these redbook CDs: http://www.arkivmusic.com/classical/album.jsp?album_id=709279, plus a quality CD player. (I definitely recommend real CD discs rather than digital downloads. The latter process can vary; it’s not always as promised.) The Mozart piano concertos are forever fresh, and always good company. Given the benefit of regular exposure, even the junior members of the household will eventually concur, although realization might take 30 years.

(8) That Belden’s type 5000 loudspeaker wire, in AWG 10 or AWG 12, as sourced from Blue Jeans Cable (https://www.bluejeanscable.com/store/speaker/index.htm), will perform (and measure) every bit as good—or better—than anything else that you can buy, at any price, including the most exotic audiophile hi-end speaker cable from any source, anywhere. Science knows best.

(9) That you can be assured of top quality performance and long term zero-maintenance listening if you select compatible (has proper input/output impedance, correct stage gain) solid state components, and install your equipment in a stable and secure manner, in a logical layout, with adequate ventilation (no “stacking”). Assuming normal residential EMI environs and interconnect lengths that don’t exceed 1 meter (self-powered subwoofers excepted, and not an issue), good RCA style cordage will assure noise free performance that’s fully equivalent to what you’d get with an XLR hookup.

(10) That a good FM tuner (+ proper antenna) can still be a desirable input source if you have access to a reliable signal from a non-commercial public broadcast station that transmits classical music via the HD-FM process. (See https://en.wikipedia.org/wiki/HD_Radio.) I live on the central coast of California, midway between Los Angeles and San Francisco, where we have a local low power repeater that relays the HD-FM signal from KUSC/Los Angeles, the last non-commercial public radio station in the U.S. that’s dedicated exclusively to classical music, 24/7. (No NPR, no PRI, no news, no jazz or folk music—it’s purely classical*.) KUSC does much of this with live in-studio program hosts, so the music is properly identified, and there’s a concurrent playlist on their website. KUSC’s transmission consumes the full 96 kbps bandwidth of their federally licensed HD-FM allocation (no HD subcarriers), so listeners can access the best possible HD-FM broadcast fidelity. If you tune in with a top quality FM-HD receiver that’s optimally aligned, the sound is totally free of noise, with wide frequency response and fine dynamic range. It’s a whole lot better sound from radio than you ever heard before!

*Well, their programmers seem to feel that movie themes (think Star Wars) are classical too. There’s a bit too much of such John Williams’ music for me, but that might be more welcome in other galaxies.

BG (August 2019)

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