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Interconnect Prototypes

Galibier Design - Interconnect PrototypesI was going through my notes on the final round of cable prototypes.  This was the group of cables that pointed toward the production cable, and I invited Lynn Olson over for a listen.

Since Lynn has been an advocate of cotton for longer than I, I knew he’d welcome the opportunity for a comparison.

This last group of 4 contenders pointed me toward the production build, with the only functional difference between the “winner” and the production cable being a change from the now discontinued KLE Copper Harmony RCAs to their next generation – the ETI Kryos.

If you’re interested in the lineage of the Eichman Bullet Plugs / KLE Connectors / ETI connectors, click this link (opens in new window).

In the results below, Lynn is in 100% agreement with both the ranking and the attributes I’m reporting.

The envelope please …

All of these builds employ the same litz wire in the same geometry.  The difference lies in the sleeves and RCA connectors.  In addition to the four “contenders”, I pulled out an early prototype to serve as a historical baseline.  In order – from best to worst:

  1. KLE Copper Harmony RCAs with cotton braid outer sleeve
  2. 1st generation Eichman Bullet Plugs with cotton braid outer sleeve
  3. Radio Shack polystyrene RCA connectors with bare wire (no outer sleeve) – this was a “quick and dirty” historical baseline.
  4. KLE Copper Harmony RCAs with polyester braid outer sleeve
  5. 1st generation Eichman Bullet Plugs with polyester braid outer sleeve

He said what ???

OK … what follows sounds a lot like a review, and you could accuse me of being self-serving, but what did you expect?  I’m evaluating a product that I’m readying for production, and if it doesn’t move me, then I have no business bringing it to market.

If you read this far, I don’t expect you to believe me, but I do expect to convey the musical values that I’m looking for when designing a product.  If my priorities make sense to you, then it’s on me to prove this to you in real time (trust but verify).

First and foremost, my listening priorities are musical intelligibility and expressiveness (what are the musicians saying?  are they making sense?).  I’m looking for a coherent message that the composer and performer are trying to communicate, and tonality, rhythm, dynamics and noise floor support the message.

I look at soundstage as an artifact of the recording process.  Frequently it provides good cues as to what’s transpiring musically, and spaciousness can be pleasant, although it can frequently derive from out of phase anomalies.

If you’ve ever sat 20 feet from a string quartet, you know how difficult it is to pinpoint the individual performers, and if you’re listening to a performance with audiophile terms in mind, you’re getting it all wrong.  The last thing I’m going to do at a live performance is to obsess over the exact location of the saxaphone player.

In my experience, if the system reproduces music in a compelling manner, then all of the typical audiophile attributes follow.

Having said that …

The outer jacket – who woulda thunk …

The polyester braid forced the ranking into two groups, with polyester being at the bottom.  It masked enough detail to drop the KLE Copper Harmony build into position #4.


The KLE Copper Harmonys are dramatically better than the first generation Bullet Plugs.  The noise floor in particular is startlingly low in comparison, and upper frequencies fill in the harmonic structure of acoustic bass and the blown reed of a tenor sax in a way that the instruments are both lush and incisive.  The better connectors propelled the music rhythmically.

Knowing ETI’s reputation for innovation, attention to detail, and prioritization of metallurgy (no intermediate layer of nickel between the base metal and silver plating), I have every reason to expect the ETI Kryo RCAs to raise the bar beyond the KLE Harmonys.

ETI has demonstrated a rational approach to continual process improvement, and I’ll verify this in the next two weeks.  If for some reason, they represent a step backward (highly doubtful) the KLE version is in plentiful supply and we’ll stock up on them.  I highly doubt this will be the case, but I’ll update this blog post when we receive delivery.

From worst to first …

The worst of these cables was quite good.  They made it to the “finals”, and only in comparison with the winning group were their flaws exposed.  You don’t know better until you hear it.

Three records that have been in recent rotation are:

  • Tony Rice’s “Backwaters”
  • David Grissman’s “Dawg/Jazz”
  • David Amram’s “Havana/New York”

All three have complex, interweaving musical lines, with the first two exploring various forms of jazz-influenced bluegrass and gypsy jazz.

Amram’s work has some phenomenal musicianship – predating Ry Cooder’s “Buena Vista Social Club” by some 15 years.  “Havana New York” was perhaps the harshest acid test in this session, with its complex Afro-Cuban poly-rhythms, horns and sax.  It’s very dense music and can sound chaotic when something is off.

A bit of Little Feat (“Sailin Shoes”), It’s A Beautiful Day (self-titled album), Michael Hedges (“Arial Boundaries”) and Mark Knopfler (“All the Road Running”) rounded out today’s session.

Cable #4 & #5 (both with polyester braid) had the lowest resolution.  In particular, complex lines in the Grissman/Rice/Amram records were blurred, congested, gritty, and compressed.  There was an ambiguous nature to the rhythmic structure of the music when compared with the winners.  The horns and sax in “Havana/New York” were somewhat aggressive sounding.

In comparison, cable #1s through #3 were the inverse of the polyester builds:  dynamic, incisive, communicative, rhythmically incisive (a sense of forward motion), and most importantly, more refined.  Eliminating polyester is a major positive I can’t overemphasize.

Cable #1 was airy, easeful and not the least bit etched.  There was a compelling sense of immediacy in “Havana/New York”.  The polyrhythms just made sense, and the  harmonic structure of string bass and blown woodwinds was rich and yet incisive when called for.  There was a sense of rhythmic propulsion that #2 through #5 could only hint at.  The percussive strike of the clave sounded like what it is (real wood striking wood) and it lent immediacy to the performance.

The differences between #1 through #3 (all with cotton braid) were ones of degree, although the fall-off from #1 to #2 was quite dramatic.  The KLE RCA is a significant step up from the Bullet Plug.  Delivery of the next generation ETI Kryos is much anticipated.

Radio Shack – are you kidding me?

You might find the Radio Shack RCAs to be an odd choice (cable #3 – the historical baseline cable).  Many people in my listening group prefer them to the Cardas RCAs.

Essentially, they’re a poor man’s Bullet Plug due to their low mass, with virtually no metal.  ETI Kryos they’re not, but when you’re doing proof of concept prototyping, $80 to $100 for a set of connectors can be an onerous expense when you’re building some 30 prototypes (I’ll let you do the math).

The good news is that their errors are all ones of omission.  There’s no coarseness, and you can get a good general idea of the wire before committing your build to higher quality components.  They served us well during the early stages and coming back to them validated my prototyping approach.

Interconnects vs. Speaker Cables

Interestingly, the negative attributes of polyester sleeving translates differently to interconnects than it does to speaker cables.

With the speaker cables, the intelligibility and rhythmic timing held together quite well.  There was some blurring during dense passages, but not nearly as much as with the interconnects.  The key “negative” of polyester in speaker cables was the coarse layer of grit in the upper frequencies.

I suspect the different behavior was due to the speaker cables carrying more current and producing a larger electrical field (which interacts with the polyester).

Reality Check

Lastly, and as a control, I slipped the blue polyester braid you see in the photo over cable #1, and the loss of detail was quickly apparent.  #1 now became virtually indistinguishable from #4.

If you come to Galibier to audition, we can perform this “polyester elimination demo” for you in 3 minutes – on the same cable you’re auditioning, so you can hear the effects of polyester.  Once you hear its removal, you’ll never go back.

As I referenced in an earlier post, those of you who have had success with cable lifters (putting distance between your cables and your carpet) would do well to try our cables.  It ain’t braggin’ if it’s true 😉