Listening #193: Nordost Flatline cables

Among the many bits of audio lore that never have and probably never will be aired in public is the story of the amp that ignited the reviewer's curtains. (I assume that at least some of you hoped I was going to say "pants.") I can't tell it in any great detail, partly because the reviewer in question is a friend (though not a Stereophile colleague), and I'm not sure how much of the story he wants out there. In any event, my object here is to offer a long-overdue apology, to all concerned, for having laughed at that story over the years, because it has now happened to me—not the part about the curtains, but definitely the part about the burning amp.

Yesterday, at about 5:15pm, I went into my kitchen and turned on the oven to pre-heat it. Ten minutes later, my wife and I both commented aloud about a strange, plasticky smell in the house. Naturally, suspicion fell on the oven—which, it turned out, contained nothing untoward. But within a matter of seconds the intensity of the smell went from zero to 60, I could see a filmy haze in the air, the downstairs smoke detector went off, and the dog started barking. Notes of panic were audible in Janet's and my voices as we asked each other, "Where's it coming from?" Then, with that clarity of mind reserved for non-audiophiles, Janet asked, "Is it the hi-fi?"

I dashed to the living room, by now the obvious source of the stink, and directed my attention to an amp that was in for review and, too big and heavy for my equipment rack, sitting on the floor. The system wasn't playing music at the time, but everything in it was powered up for that eventuality. I saw a column of smoke rising from the ventilation louvers on the amp's top plate, and below those louvers a small flame: Something inside the amp was literally on fire, a fact that my mind absorbed with only the greatest reluctance.

I urged Janet to get herself and the dog outside, which she did; a minute later I followed, but only after pulling the amp's power cord and making sure that that extinguished the flame. It did. A few minutes later, I took a couple of deep breaths of fresh air, then went back inside to open every window in the house, turn on every fan I could find, and put the chicken in the oven: as the poet William Laird wrote, "men must eat, though angels be their guests." (footnote 1)

On my next trip inside, I realized that the acrid smell was so pervasive that there was no way to tell whether the powered-down amp was still contributing to it. Nevertheless, like shooing a rabid skunk away from an outdoor wedding, getting rid of the amp seemed a reasonable precaution, so with Janet's help I dragged it out the front door and onto the front step, where it sat for an hour and a half. During that time, we had our chicken dinner in the back yard. Whether despite or because of the smoke, mosquitos ate us alive.

I didn't get much sleep that night, owing to the lingering stink—which had reached almost every corner of our home—and to my lingering worries about potential carcinogens. In the morning I set about cleaning the house, which proved a lengthy task: three days of scrubbing walls, ceilings, hardwood floors, and hardwood furniture, often multiple times—even after four washings, the wall behind the amp continued to reek—plus laundering bedsheets, pillowcases, slipcovers, and clothes that had been neither shut away in a closed drawer nor hung in a closed closet. Rugs and upholstered furniture were sprinkled with baking soda and vacuumed multiple times, and windows and other glass surfaces were washed twice. The dog got a bath, which she appeared to enjoy.

I contacted the manufacturer, who was equal parts horrified and apologetic. He vowed that no such accident had ever before befallen one of his products, and I believe him: Especially in our Google-review age, things like that get out.

The amplifier in question is a solid-state product of moderate output power that had performed admirably for the two weeks before the day of the fire—and during use, its case was never more than warm to the touch. (The curtain-burning amp mentioned in my opening paragraph, which remains in production and is in fact a truly fine-sounding amp, runs notoriously hot.) As I write this, a postmortem has yet to be performed on the new amp's innards, but a glance through the now-sooty louvers suggests that the cause was a failed electrolytic capacitor.

If there were even the slightest chance that naming the manufacturer would spare someone else this inconvenience and potential danger, I would do so, but the law of averages suggests that the next time a modern electrolytic capacitor fails in such spectacular fashion, it will be in the power supply of a product from a different company. (For the cynics among our readers: The company in question is not, and never has been, an advertiser in Stereophile's pages.) I'll have no part in putting a manufacturer out of business, and his employees out of their jobs, because one cap among the hundreds he buys each year unforeseeably failed.

However, bending to demands from my family, I have declined a second review sample, a refusal that the manufacturer acknowledged with good grace.

I've also decided to alter my listening and reviewing habits. (I love writing about policies: they're easier to unpack than anything else, easier to lift, and it doesn't cost a dime to send them back from whence they came.)

No, you run it in
Mandolinist David Grisman has a lot of great stories about the times he traveled with and performed alongside his hero, mandolinist Bill Monroe (1911–1996), the father of bluegrass music. My favorite: One time, at a bluegrass festival, a young woman approached Monroe and asked if she could take his picture. He assented, and when she asked if he could step back a little, he graciously did so. But when, while framing the shot and fiddling with her camera, she asked him to step back a little farther, Monroe replied, "No, you step back!"

The burning amp in my living room had escaped my attention, presumably for at least a few critical minutes, because I'd left it powered up all afternoon, to ensure its optimal performance during an after-dinner listening session. The outcome was unexpected, but the lead-up was standard operating procedure. Special emphasis on was.

Beginning with the Amber Series 70 power amp and NAD 1020 preamp I owned in the early 1980s, I tended to leave solid-state amplification components powered up 24/7, except during electrical storms or protracted absences from home. I've been more circumspect with tube amplifiers, but I've also been known to power up tube preamps first thing in the morning and power them down only at bedtime—and I was never terribly concerned on the many occasions when I absentmindedly left them powered up overnight. (I broke that habit a little over 10 years ago, when I bought my first products from Shindo Laboratory, which use mostly hard-to-find, NOS tubes. I came to learn that those tubes are usually operated conservatively in terms of their plate voltages, and that Shindo's amps and preamps alike perform exceptionally well after a mere 20 minutes of warm-up.)

Elsewhere in this issue I review the Cary CAD-805RS monoblock amplifier, whose manufacturer recommends 100 hours of run-in time. Other manufacturers observe that similar or longer—sometimes much longer—periods of time are required for their products to sound their best. I've even encountered a manufacturer of cables—cables, for God's sake!—who says that his products require a minimum of 300 hours before they can be properly evaluated. Assuming one listens to one's playback system for three hours a day, seven days a week, that means one's presumably very expensive high-end cables won't sound good until more than three months after their purchase date. It makes the idea of a 10-day home trial sound a bit silly.

Although the unlucky manufacturer in this story made no such demands, I intend from now on to ignore admonitions to leave review samples powered up around the clock. If a manufacturer wants me to review a product that's incapable of sounding good without more than a month of steady use, he or she has two choices: run it in themselves—not an unreasonable request especially for paying customers and for products with five- and six-figure price tags—or don't send it at all.

Flatline resurrected
Long ago, in the Spring 1996 issue of Listener, I wrote about Flatline and SuperFlatline speaker cables from the then-newish Nordost Corporation (footnote 2). Flatline was made with four flat copper conductors per run, separated from each other and from the cable's adjacent run with clear Teflon, also pressed flat; SuperFlatline was doubled-up Flatline, with eight conductors per run, thus 16 conductors per channel.



Footnote 1: "Traumerei at Ostendorff's," from The New Poetry: An Anthology, Harriet Monroe, ed. (MacMillan, 1917).

Footnote 2: Nordost, 93 Bartzak Drive, Holliston, MA 01746. Web: nordost.com.

ARTICLE CONTENTS

COMMENTS
Charles E Flynn's picture

The burning of some types of plastics produces soot that is not only annoying, but is corrosive as well. If the soot is not promptly removed from metal surfaces, they can be permanently damaged. I learned this after a fan in a router in a closet failed and filled half of the floor of a large building with soot. It took weeks for a team of people equipped with Nilfisk vacuum cleaners to complete their task. They had to clean thousands of objects while keeping them in order.

I was expecting you to discover that the cause of the fire was a failed fan. I once asked a maker of expensive hard drives that were intended to be as reliable as possible if they had particularly reliable fans, and was informed that "there are no suitable fans made in Switzerland".

Once you have had a fire, your relationship with fire is forever changed.

Anton's picture

My first recollection of Art in the Hi Fi publishing business is 1985.

He's probably been into Hi Fi even longer than that, but I will run with 1985.

In the past 33 years, you've had one flaming mishap.

If you pretend this never happened and keep doing things as you've always done, odds are the Grim Reaper will have discovered an alternate method for calling you home long before you'd experience another flaming amplifier.

If you really want to stack the odds in your favor, have Oswald Mills make you a slate amplifier platform and the worst that would happen is you end up making a sacrifice to the old Gods.

Glad you are OK!

tonykaz's picture

Amp designers are often talking about prototype amps burning.

Jason Stoddard is willing to regale us with his schiity design failures.

I hope you didn't inhale those toxic plastics.

Tony in Michigan

ps. Schiit Amps that I've owned don't catch fire or sound bad, they're quite good sounding, the Asgard 2 is OUTSTANDING!!!

AaronGarrett's picture

Del McCoury tells that story on Bluegrass Mandolin Extravaganza I think.

Ortofan's picture

... the amplifier's manufacturer, then would he be more willing to mention the brand of capacitor that failed?
Also, is it possible that the cap was installed backwards?

jmsent's picture

....could not possibly do so with a backward installed electrolytic capacitor. They simply will not function if reverse polarized and the capacitor would self destruct within seconds. There's not enough info here to ascertain what actually happened, and without actually seeing the amplifier, nobody can know for sure. Having worked on the technical side of the audio business for many years, I've seen my share of amplifier failures. Especially in the early days of high power solid state when failures were so common that compainies like Phase Linear were given the nickname "Flame Linear". But those failure were almost never from electrolytic capacitors. They were almost always due to failure of a transistor, causing a chain reaction of failures in the circuit, and burning up a few resistors along the way. They could certainly cause a small fire on the circuit board, and the stink was pretty intense. However, carbon resistors are seldom used today and transistors are way more reliable, so you would not normally see these kinds of failures anymore.
One issue that has cropped up in recent years is the growth of counterfeit components, including electrolytic caps. Ebay is overrun with them, and they sometimes even sneak into the inventory of trusted electronic distributors. Here's an interesting article (one of many) https://creativeelectron.com/2014/08/10/counterfeit-components-explode/

CG's picture

You've got that right!

Part of my day job is to do forensic engineering on equipment that fails in testing or in the field. A "one of" failure out of a zillion units usually isn't of much concern. You explain the statistics and move on. But, more than that one is an issue.

I'd say that after soldering errors in manufacture, electrolytic failure is the next most common malady.

Like most electronic components, electrolytic cars have more subtleties associated with their care and feeding than you can imagine. These are all described in the data sheets, right there in the large section everybody skips over. There's application notes galore. You can easily spend a solid week learning about proper electrolytic capacitor use.

Running electrolytic caps at an elevated temperature really degrades their life span. Same for running them too close to the specified voltage maximum. Presumably the amplifier manufacturer has taken all that into account.

But, that counterfeit cap thing is a very real problem. (It's not just caps, either... Semiconductor fakery is BIG business.) Sometimes what you find is a cap that looks right from the outside, with the right labeling, the right physical appearance, and is the right physical dimensions. But, if you take a can opener to it you find a much smaller cap inside that is wired to the proper can terminals. Smaller usually means lower capacitance, higher ESR, and maybe lower maximum operating voltage. All of those can conspire to let the cap overheat, sometimes to the point of catching on fire.

Or, it could just be bad luck for that one cap...

John Atkinson's picture
jmsent wrote:
I've seen my share of amplifier failures. Especially in the early days of high power solid state when failures were so common that companies like Phase Linear were given the nickname "Flame Linear".

Back in the mid-1970s, our band had 3 Phase Linear amplifiers: 1 for the left PA speaker stack; 1 for the right speaker stack; 1 being repaired from the night before.

John Atkinson
Editor, Stereophile

Bogolu Haranath's picture

May be that's the reason why you (JA) became an audio equipment reviewer, who also does measurements .......... May be we should thank Phase Linear for that :-) ..........

jimtavegia's picture

Planning ahead is always good.

Ortofan's picture

... backward installed electrolytic capacitor will "self destruct within seconds", regardless of how much - or how little - voltage is applied to it?

jmsent's picture

1. A rather large capacitor, given how much smoke filled Art's house when it failed.
2. The large capacitor having considerable voltage across it and considerable current being dissipated through it when it failed; e.g. a filter capacitor.
A small electrolytic capacitor installed backwards with low voltage across it would be highly unlikely to fail in such a spectacular manner.
It's all speculation anyway, and given the small amount of info, we can't even know if it was a capacitor that failed.

Long-time listener's picture

I recently bought an Audioquest Diamond coaxial digital cable. While I've had components that benefitted from break-in, I thought that the dialectric biasing system would probably render that unnecessary. So when I first connected it I was terribly dismayed at the bright, harsh, metallic sounds I got. But it really did break in over a period of about 20 hours, and now sounds fine.

Bogolu Haranath's picture

May be AD was playing Rap music too loud for too long :-) ..........

rschryer's picture

A week ago, my son and I were listening to Eminem's "Killshot" (a blisteringly fun retort to Machine Gun Kelly's "Rap Devil", a song in which MGK has the audacity to challenge Eminem's rapping skills) on my system when the bass driver on one of my speakers gave out.

BTW, I'm proof that you don't have to (generally) like rap to recognize rapping talent. For anyone curious enough, may I suggest checking out MGK's track on Youtube, then Eminem's. Eminem is at his best when challenged.

Just don't play the music too loud. :-)

Bogolu Haranath's picture

"Rap music is capitalistic ......... It is aimed at making money" .......... A Rap music fan :-) ........

tonykaz's picture

I thought it was Outlawed & Banned throughout Polite Canada. Egads!

Maybe you snuck over the Seaway to some Sleezy US listening post.

My own ears have nevah gotten any closer than a Way Too Loud Car on the Expressway.

I guess Rap explains the messy hair is the little photo, hmm. ( I hope that tilt to the Right isn't permanent damage from dubious Live Performances).

Lets hope JA doesn't penalize you for this "confession".

Tony in Michigan

ps. I once listened to Inna Godda De vita, after which I washed my face & hair with Holy Water & and said 3 Rosaries. ( that was before I became a Proud Pagan )

rschryer's picture

...from my last AWSI, Dr. Alyson's second rule: "You let your family decide what music to play." This includes rap. And it can still be fun and rewarding.

Oh, and my hair isn't messy; it's wavy. And that head tilt to the right has nothing to do with any damaging effect rap has had on my brain; it's just me striking my "casually confident" pose so people think I have my act together.

(I do hope that last admission won't hurt my chances of becoming President of an International Organization Recognizing Excellence in Audio Engineering.)

Charles E Flynn's picture

Two excerpts from https://www.resolvebylowes.com/guidance/fire/how-smoke-damages-a-home/11... :

Discoloration


 
Shortly after a fire, the effects of smoke damage are visible on walls, ceilings and surfaces, appearing as stains and discoloration. Within a few days, walls and flooring may begin to turn yellow; however, this yellowing affect doesn't show right away. Plastic surfaces/appliances and wood can also become discolored and warped. Several hours after a fire, metal hardware can show signs of rust and corrosion. If you have countertops, tiles or other surfaces that contain porous stone such as marble, granite or travertine, they usually become permanently discolored from the acidic residue found in soot. This residue can also permanently tarnish metals.

Corners


 
When smoke particles are ionized - or have an electrical charge - they are attracted to certain surfaces. Smoke produced by burning plastic carries a stronger charge than smoke from wood, paper or cotton. This causes smoke residue to form in clusters that look like cobwebs in the corners of rooms where walls and ceilings meet.

HammerSandwich's picture

I understand that this failure is an exceptional case & very probably not a design or build issue.

But hasn't JA stated that all products submitted for review will be reported on? How does Stereophile now align that policy with the current lack of disclosure? What is the (new?) policy on exceptions to the general rule?

Charles E Flynn's picture

Back when Roy F. Allison was vice-president of Acoustic Research, the products came with this disclaimer or one very similar. I wish I had saved a copy.

"Acoustic Research products, in common with all made-made objects, can develop defects in transportation, storage, or use."

jimtavegia's picture

Fire and smoke are the worst clean up ever. People don't realize what has to be done.

I had my condenser pan in the whole-house AC fail last summer and water flooded my man-cave, luckily in the basement. Once cleaned up and new carpet, paneling, etc., back in operation. Water, if contained, a much easier job. No black mold luckily.

Hope the equipment mfg is helping. Your new place seems very nice.

Howard's picture

If an amp (or another piece of equipment) is in standby mode, does that protect one from this kind of nightmare, or is powering down completely the only way to be totally safe? Thanks.

jimtavegia's picture

The only safe way.

Bogolu Haranath's picture

Exploded view (album) ........... Exploded view :-) ............

romath's picture

So are you telling readers that for the past 22 years you haven't been running in cables before reviewing them? Everything needs burning in, adjusting to new surroundings. No matter what manufacturers or developers say, cables typically take at least 400-500 hours to realize their potential, although sometimes around 300 one can have a good idea. It's hard to fathom that a writer for Stereophile doesn't know this...

rschryer's picture

...are a breath of fresh air, in the subjective sense.

Anton's picture

Everybody says they can hear cables break in, but nobody talks about the other end of their lifespan.

Most cables start to phone it in after an additional thousand hours, or so. 'Oxygen free' is not an eternal state. Silver starts to oxidize, cables get older and the crystalline structure changes, micro-fractures occur ever time they are handled. Those stupid things can have shorter life expectancies shorter than some cartridges.

I know people who've had the same tonearm wiring for decades. The thinner the gauge, the shorter the lifespan. Just ponder how often they have to move! Don't even get me started about the wire wrapping, insulation, etc.

Home wiring can be given a 100 year life expectancy, but high end audio isn't the same big gauge crude stuff like they use for plain old home wires.

This topic is rarely addressed, but is not less valid than cable break in.

How often to do you change out cables?

romath's picture

Perhaps it's not talked about because it is not common! Sure, there's oxidation over time, but that can be cleaned - even replugging can do wonders. And sometimes there's maybe some poor quality plastic that leaches, although with better stuff that's rate. But one will search a very long time to find anything remotely backing your "not less valid" claim.

Anton's picture

To paraphrase Dirty Hi Fi Harry, a man’s gotta know his cable’s limitations.

The hip kids will catch on and the discussion about the other sonic end of cable life will become a given. Do you think cable simply stops changing after your 500 hour claim?

It’s a bell shaped curve, with some cables being able to stretch their peak time vs. others.

Happens with many audio parts, I wouldn’t think it would be controversial. After break in, does anyone think gear enters an indefinite period of suspended animation?

romath's picture

No, after 500 hours it keeps getting better! Interesting that you've yet to cite any sources except "I know people."

Anton's picture

I heard the same argument from people who said wires didn't make a difference back in the day.

Keep listening, you'll get there! What breaks in, breaks down.

If you want citations, where is you data regarding "it keeps getting better after 500 hours?"

Is this an infinite progression for you?

I guess we should be buying cables from the telegraph days?

romath's picture

Still waiting for your evidence...

Anton's picture

Do you have some sort of objective measurement that shows your cables keep "getting better" up to or after 500 hours, or did you come across that by listening?

My advice: don't quit listening for break in and then quit in contented satisfaction expecting an eternity of "improved." Keep your critical faculties tuned for other changes over time.

Works with capacitors, tubes, turntable belts, cartridges, etc...like I said: "If it can break in, it can break down."

If you are able, simply start with Google and check changes in micro-crystalline structure, tensile behavior, etc. as wires age.

romath's picture

Ah, here we go... Scratch a cable cynic and out comes "objective measurement." But this time rather on the front end, it's the back. LOL. Good bye.

Anton's picture

As I pointed out, I listen.

I can hear an aging cable, you apparently cannot. You demand citations...then what citations do you have for ongoing improvement after 500 hours of break in?

I think the tail is wagging the dogma with you. You believe as "citations" tell you, but don't bother to keep listening?

Feel free to hear as you are told. I would advise you to listen in the longer term.

How old is your oldest cable? Do yours keep improving indefinitely? If not, do you think they peak and remain there for a century or two?

I find your premise ridiculous, and it smacks of you having learned to parrot what others tell you without listening with your own ears.

All I ask is that you question whatever "citations" you are relying on and listen. You say cables can only improve over time, but never diminish? That's a little bit funny.

There is ample "old fashion" materials science that shows wiring and metals change over time, why would you dispute that or call it cynical?

Are you at least careful not to keep bending and rebending your cables? If so, why?

I think we have run into a dogmatic rule based audiophile who runs with some rule based dogma about cables.

Think, my friend!

Bogolu Haranath's picture

AD is saying (singing) ...........

"I'm Alright" ........... Kenny Loggins (Theme from 'Caddyshack') :-) ..........

Bogolu Haranath's picture

Go 'wire-less' ......... Start listening to Bluetooth/wi-fi speakers :-) ...........

Bogolu Haranath's picture

Breaking bad? :-) .........

"Breakdown" ........... Tom Petty & The 'Heartbreakers' :-) ...........

"Breakdance" ............ Irene Cara :-) ...........

Relayer's picture

The Breaks- Kurtis Blow

irrelevant's picture

"unfortunately for manufacturers, Stereophile's policy is to review products that appear to be working as received, and if units with a below-par performance have slipped through the manufacturer's quality control net, then we assume that that can happen to readers also.​"

This is a quote from John Atkinson, January 1987 (Vol.10 No.1). Has Stereophile changed its policy in the intervening years, or just made an exception for this recent incident?

Zavato's picture

I had the same thought and had long believed it was Stereophile’s policy to report all experiences with gear in for review. Yes, there have been times when Stereophile deviated from its policy but years back JA assured readers that Stereophile would never again throw a well-reasoned policy into the wind (Vol. 15 #9). If an amp caught on fire in ADs home it can happened to any consumer buying the same amp. Whether it’s statistically unlikely really isn’t the point.

John Atkinson's picture
Zavato wrote:
I had the same thought and had long believed it was Stereophile’s policy to report all experiences with gear in for review. Yes, there have been times when Stereophile deviated from its policy but years back JA assured readers that Stereophile would never again throw a well-reasoned policy into the wind (Vol. 15 #9).

Art discussed this with me when we were preparing the January issue and did explain in this column why he felt an exception to our policy was justified.

John Atkinson
Editor, Stereophile

Bogolu Haranath's picture

"The young man knows the rules, but the old man knows the exceptions" ........ Oliver Wendell Holmes Sr. :-) ............

Nootje's picture

I am a bit surprised that you compare the Nordost cables with Luna Red speaker cables in your main system. You used to listen to Auditorium 23 speaker cables many years. I think that would be a more interesting comparison if you look at the price.

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