On “Hi-End” AC Line Cords…

By Bryan Geyer

I always wonder if anybody using esoteric “high end” AC power line cords has paused to consider the household wiring on the other side of their own listening room wall. That wire is ordinary AWG 12 Romex if it's for a 20 ampere circuit breaker, or (more likely) AWG 14 Romex if it’s for a 15 ampere circuit breaker. And what about that other ~ 10 miles of power line cable that extends back to the local distribution yard? Hey, can your AC power line purity really be improved by adding that last few feet of costly “audiophile grade” power cord?

The short answer is: Who cares? All of those alternating current pulses, however fine or fuzzy, are going to be converted into a smooth, flat stream of direct current. It's only this strained and purified DC, not any spurious AC, that will operate the ensuing electronic circuits. A modern solid state linear power supply utilizes full wave AC-to-DC rectification with very heavy filtering. Active components are added to enhance DC stability. Zener diodes clamp voltage levels and chop ripple. Precise series regulator stages are implemented where there’s justifiable merit, and high capacity electrolytic filter capacitors are used throughout, to assure good inter-stage isolation and smooth DC reserve. The consequent supply is scrubbed free of extraneous AC artifacts--it’s just plain/pure/smooth/steady direct current, and you can view and verify that flat DC waveform on an oscilloscope.

While every audio component has its own unique DC power supply, every supply draws its AC fuel from the same source, so it’s vital to provide enough AC current to run all the DC engines--refer paper “On Assuring Adequate AC Power.”  The latter addresses cumulative AC line current drain.

AC power line cords serve as pipelines that route the required AC fuel to each DC engine. There’s no benefit served by making the pipe fatter than needed. Every DC engine has a basic design task, and it can’t store or utilize any excess AC fuel. Power line cord delivery capacity is defined by its conductor diameter. The original circuit designer selects a wire diameter gauge (AWG) that’s appropriate for the AC current required. If you have need for a shorter or longer cord, or perhaps one with an angled C13 connector (to reduce rear clearance—see photos), simply let the designer’s original AWG be your guide. Increase the diameter if you have to extend the cord (by some appreciable amount) beyond its original reach. Technically, there’s no harm incurred by moving to the next fatter gauge--I personally favor utilizing AWG 14 for a stereo power amplifier that was shipped with AWG 16 wire—but nothing whatever is gained by moving to grossly oversized cordage like AWG 10 or 12. Such cords serve no benefit, and become awkward handling and routing annoyances that invite problems.

With respect to AC line cord construction and insulation, the heavy-duty commercial standard for prime quality is type SJT, with molded construction. It’s quite excellent, and all that you’ll ever need.

Be aware that you can buy top quality SJT molded AC line cords, in AWG 14, 16, or 18, that’s made to any desired length--refer http://www.stayonline.com/molded-cord-configurator.aspx. The price for such custom cord will be quite low when compared to a high-end “audiophile grade” line cord, but it will be functionally equivalent and of optimum length, with no need to hide coiled excess. Do utilize AC surge protection at the feed socket; it might help if there’s some aberration on the power line.

BG (March 2019)

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Meet the Staff

Meet the Staff
John J. Puccio, Editor, Publisher, Reviewer

Understand, I'm just an everyday guy reacting to something I love. And I've been doing it for a very long time, my appreciation for classical music starting with the musical excerpts on the Big Jon and Sparkie radio show in the early Fifties and the purchase of my first recording, The 101 Strings Play the Classics, around 1956. In the late Sixties I began teaching high school English and Film Studies as well as becoming interested in hi-fi, my audio ambitions graduating me from a pair of AR-3 speakers to the Fulton J's recommended by The Stereophile's J. Gordon Holt. In the early Seventies, I began writing for a number of audio magazines, including Audio Excellence, Audio Forum, The Boston Audio Society Speaker, The American Record Guide, and from 1976 until 2008, The $ensible Sound, for which I served as Classical Music Editor.

Today, I'm retired from teaching and use a pair of bi-amped VMPS RM40s loudspeakers for my listening. In addition to writing the Classical Candor blog, I served as the Movie Review Editor for the Web site Movie Metropolis (formerly DVDTown) from 1997-2013. Music and movies. Life couldn't be better.
Karl W. Nehring, Contributing Reviewer

For more than 20 years I was the editor of The $ensible Sound magazine and a regular contributor to its classical review pages. I would not presume to present myself as some sort of expert on music, but I have a deep love for and appreciation of many types of music, "classical" especially, and have listened to thousands of recordings over the years, many of which still line the walls of my listening room (and occasionally spill onto the furniture and floor, much to the chagrin of my long-suffering wife). I have always taken the approach as a reviewer that what I am trying to do is simply to point out to readers that I have come across a recording that I have found of interest, a recording that I think they might appreciate my having pointed out to them. I suppose that sounds a bit simpleminded, but I know I appreciate reading reviews by others that do the same for me -- point out recordings that I think I might enjoy.

For readers who might be wondering about what kind of system I am using to do my listening, I should probably point out that I do a LOT of music listening and employ a variety of means to do so in a variety of environments, as I would imagine many music lovers also do. Starting at the more grandiose end of the scale, the system in which I do my most serious listening comprises an Arcam CDS50 CSD/SACD CD player, Goldpoint SA4 Passive Preamp, Legacy Audio PowerBloc2 amplifier, and a pair of Legacy Audio Focus SE loudspeakers. I also do a lot of listening while driving in my 2016 Acura RDX with its nice-sounding ELS Studio sound system through which I play CDs (the ones I especially like I rip to the Acura's hard drive so that I can listen to them whenever I want) or stream music through the system using my cell phone. For more casual listening at home when I am not in my listening room, I often stream music through the phone into a Vizio soundbar system that has remarkably nice sound for such a diminutive physical presence. And finally, at the least grandiose end of the scale, I have an Ultimate Ears Wonderboom Bluetooth speaker for those occasions where I am somewhere by myself without a sound system but in desperate need of a musical fix. I just can't imagine life without music and I am humbly grateful for the technology that enables us to enjoy it in so many wonderful ways.
Bryan Geyer, Technical Analyst

I initially embraced classical music in 1954 when I mistuned my car radio and heard the Heifetz recording of Mendelssohn's Violin Concerto. That inspired me to board the new "hi-fi" DIY bandwagon. In 1957 I joined one of the pioneer semiconductor makers and spent the next 32 years marketing transistors and microcircuits to military contractors. Home audio DIY projects remained a personal passion until 1989 when we created our own new photography equipment company. I later (2012) revived my interest in two channel audio when we "downsized" our life and determined that mini-monitors + paired subwoofers were a great way to mate fine music with the space constraints of condo living.

Visitors that view my technical papers on this site may wonder why they appear here, rather than on a site that features audio equipment reviews. My reason is that I tried the latter, and prefer to publish for people who actually want to listen to music; not to equipment. My focus is in describing what's technically beneficial to assure that the sound of the system will accurately replicate the source input signal (i. e. exhibit high accuracy) without inordinate cost and complexity. Conversely, most of the audiophiles of today strive to achieve sound that's euphonic, i.e. be personally satisfying. In essence, audiophiles seek sound that's consistent with their desire; the music is simply a test signal.

William (Bill) Heck, Contributing Reviewer

Among my early childhood memories are those of listening to my mother playing records (some even 78 rpm ones!) of both classical music and jazz tunes. I suppose that her love of music was transmitted genetically, and my interest was sustained by years of playing in rock bands – until I realized that this was no way to make a living. The interest in classical music was rekindled in grad school when the university FM station serving as background music for studying happened to play the Brahms First Symphony. As the work came to an end, it struck me forcibly that this was the most beautiful thing I had ever heard, and from that point on, I never looked back. This revelation was to the detriment of my studies, as I subsequently spent way too much time simply listening, but music has remained a significant part of my life. These days, although I still can tell a trumpet from a bassoon and a quarter note from a treble clef, I have to admit that I remain a nonexpert. But I do love music in general and classical music in particular, and I enjoy sharing both information and opinions about it.

The audiophile bug bit about the same time that I returned to that classical music. I’ve gone through plenty of equipment, brands from Audio Research to Yamaha, and the best of it has opened new audio insights. Along the way, I reviewed components, and occasionally recordings, for The $ensible Sound magazine. Recently I’ve rebuilt--I prefer to say reinvigorated--my audio system, with a Sangean FM HD tuner and (for the moment) an ancient Toshiba multi-format disk player serving as a transport, both feeding a NAD C 658 streaming preamp/DAC, which in turn connects to a Legacy Powerbloc2 amplifier driving my trusty Waveform Mach Solo speakers, supplemented by a Hsu Research ULS 15 Mk II subwoofer.

Mission Statement

It is the goal of Classical Candor to promote the enjoyment of classical music. Other forms of music come and go--minuets, waltzes, ragtime, blues, jazz, bebop, country-western, rock-'n'-roll, heavy metal, rap, and the rest--but classical music has been around for hundreds of years and will continue to be around for hundreds more. It's no accident that every major city in the world has one or more symphony orchestras.

When I was young, I heard it said that only intellectuals could appreciate classical music, that it required dedicated concentration to appreciate. Nonsense. I'm no intellectual, and I've always loved classical music. Anyone who's ever seen and enjoyed Disney's Fantasia or a Looney Tunes cartoon playing Rossini's William Tell Overture or Liszt's Hungarian Rhapsody No. 2 can attest to the power and joy of classical music, and that's just about everybody.

So, if Classical Candor can expand one's awareness of classical music and bring more joy to one's life, more power to it. It's done its job. --John J. Puccio

Contact Information

Readers with polite, courteous, helpful letters may send them to classicalcandor@gmail.com

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"Their Master's Voice" by Michael Sowa

"Their Master's Voice" by Michael Sowa