KLEI gZero6 Speaker Cable Review

Fresh on the heels of the KLEI Speaker Cable Review on this blog, the guys at KLE Innovations (KLEI) sent me a pair of their top-of-the-line KLEI Zero6 Speaker Cables to review.


At first glance, the
KLEI gZero6 Speaker Cables look almost identical to the KLEI gZero2, but it appears to have a second conductor on the neutral line, as can be seen by the twisted conductor in the photo above. This is an indication that they utilize an enhanced implementation of the KLEI gZero cable architecture in the neutral line whereas the signal line appears identical.

Having now reviewed almost all of the items in the current KLEI Product Line-up, this being the last product to review, I've come realize that you really cannot
"judge these books by their covers"

SIDE BAR: The "Looks"Conundrum...

I am constantly amused by comments made in audio circles about the looks of cables and connectors. The nice gold or rhodium plating, the in-vogue carbon fibre look etc..

After all, cables generally sit behind the components and are seldom seen, unless of course you have the big mono-block amps that need their very own one cubic yard of open space and generally located to the front and between the speakers, since they provide some very pleasing
“Eye-Candy" - BUT CABLES?

So I ask - aren't the looks of a cable secondary to how they actually perform?

Not that any of the KLE Innovations cables look cheap - they are very nicely made, with a very understated appearance.

Anyhow, Back to the Books and their Covers....

So what is "under the covers"?

KLE Innovations take their competitive design advantage very seriously, so what is on their web site is about all you will find out about their construction methods.

Basically, they use a combination of very high quality copper and/or silver conductors that are constructed in accordance with
“KL's gZero architecture", which combats the effects of electrical noise that is induced into conductors from adjacent conductors and also all connected components during normal operation.

More Detail you say?
(extract from my KLEI gZero2 Speaker cable review)....

The Issues...

When you have two (or more) insulated adjacent (i.e. parallel) conductors, i.e. as in most “conventional” cable designs, the following issues can arise...
  • When an AC voltage is applied to one conductor, electrical "noise" will be induced into the adjacent conductor(s)
  • two adjacent cables will experience reactive/EMF/EF effects due to the cable's inductance and capacitance which varies with frequency
  • long straight wires are also prone to RF/EMF/EF effects from external sources
  • there is also "ground noise" which is introduced by the actual components attached to the cables.

But the team at KLEI has come up with a very different approach…
  • Their Goal: “The KLEI gZero architecture dynamically works to maintain a zero voltage Ground state”
  • Their approach: “In accordance with KL’s Signal/Ground Formula, the KLEI gZero architecture is comprised of hand wound conductors, and implemented in a manner to dynamically enhance electron flow in the Signal conductor, without the use of electronic components.
  • The Result: “This has the effect of protecting the signal conductor from ground induced capacitive and inductive reactance, which facilitates smooth uninterrupted signal flow from one component to another, effectively isolating them and allowing them to perform their task without interference.”

So, if their design works, then you should have about the purest transmission of a signal from one component to the next - Yes?

So - Did Their Design Work?

Yep! - there ya go! - they're awesome! - go out and buy them! - I'm done! Happy

But for those of you that would like further detail about their performance...

Thanks to the team at
KLE Innovations the cable set I received had undergone Factory Burn-in, otherwise I would have been faced with a recommended burn-in period of around 300 hours. As is, KLEI still suggested I allow 3 days before any serious listening.

But right from the first track, one improvement was very apparent, the extension to the bottom end was significantly lower with more control and more bass detail (not to be confused with "more bass" as in bloating)

This was an extension in
KLEI gZero2 Speaker Cables.

As time went by the openness of these cables made for an extremely open and realistic presentation, especially on tracks that were not
"over engineered" i.e. most classical albums, jazz albums and live performances. Even the over extended bass lines often present on R & B albums were still very well controlled and not prone to bloating, as can sometimes be the case.

Some tracks that really highlighted their openness include...
  • Norah Jones: Not Too Late - beautifully engineered in it's simplicity, very few effects are applied to her voice making for a truly individual performance
  • Norah Jones: My Little Room - even better, Just Norah, a guitar and Double bass - all in my living room playing to me.
  • Nellie Furtado: Saturday - again wonderful simplicity in the engineering with Nellie, an acoustic guitar, background vocalist and the natural acoustics of the studio - the fun they were having was superbly conveyed.
  • P!nk: Crystal Ball - just P!ink, a guitar and a harmonizing vocalist - simple, but incredibly pure
  • With this combination of excellent sound engineering and the KLEI gZero6 Speaker Cables - an artist has no where to hide imperfections.

As the burn-in period completed, the dynamics, openness and clarity these cables conveyed, for me, became their
“defining signature".

As my auditions progressed I also became aware that I was listening at a significantly louder level than normal, which for me is unusual, because I normally find loud music very difficult to focus on.

  • It seems these cables allows the amp to fully control the speakers such that the detail and clarity was never overwhelmed by a single instrument, e.g. drums or bass, that can sometimes occur when played at loud volumes.

In this respect, the album I had most fun with was Roxette's
Don't Bore Us - Get To The Chorus (Greatest Hits). It is possibly the most Dynamic album I have in my collection, with incredibly dynamic drums, piercing guitar riffs, deep synth work and very punchy bass lines.
This album alone demonstrated just how good the
KLEI gZero6 Speaker Cables are at exerting complete control over my speakers - even when played REALLY LOUD!. Happy

Out of curiosity, I reconnected the
KLEI gZero3 Interconnects, since I felt that their performance might also benefit from the extended abilities of the KLEI gZero6 Speaker Cables.
  • As suspected, they contributed nicely to their performance, elevating them to a more realistic and natural reproduction.
  • But when used in combination with the KLEI gZero6 Interconnects, they transport you into the heart of the performance.

Reflecting back on the performance of the
KLEI gZero2 Speaker Cables, I recall listening to them for the first time had me wondering whether the cables were colouring the sound, mainly because some of the more "engineered" tracks sounded so different.
  • To verify this was not the case. I turned to classical albums to assess their reproduction accuracy, which reassured me they were completely neutral and well balanced in their delivery.
  • Since the KLEI gZero6 speaker cables perform to an even higher level, listening to them for the first time may accentuate this phenomenon, so take time to audition a lot of tracks - they will astound!

So I guess, with more of everything and no downside,
KL’s Signal/Ground Formula has proven itself. Not only as a theory, but in a very practical demonstration at a level of performance I had not expected to achieve with my particular system components.

Things to Consider…

As stated in the
KLEI gZero2 Speaker Cable Review - there are a couple of aspects about the KLEI gZero line of speaker cables to consider...
  • a maximum length of 5 meters, but 2.5 or 3 meters is their preferred length and they start at 2 meters long.
  • KL recommends, that to ensure optimum performance, that the audio systems Speaker impedance, especially the average, needs to be >3ohms and that the Speaker Sensitivity needs to be >83db, but as KL mentioned.

And The Pricing?

The RRP of the KLEI
KLEI gZero6 Speaker Cables is AUD$605 per 2.0 m plus $60 per additional 0.5m

Yes, they are getting up there, but again, compared to the competition they are very reasonably priced, but especially if you consider what they actually accomplish.


If you want a big, bold, controlled presentation that is , dynamic, crystal clear and spacious then the
KLEI gZero6 Speaker Cables will not disappoint.

will change the sound of your system in ways you might not anticipate.

will contribute to significant improvements in systems of all price points, elevating the performance of even modestly priced systems to levels that equal systems of a much higher price point.

But as the performance level of the system becomes more articulate, detailed and well defined, so will the performance of the
KLEI gZero6 Speaker cables.

They will allow the amplifier to take control of your speaker and bring out their best performance.

KLEI gZero Cables are a family, they augment each others abilities, so it really does not matter which combinations you select - they will perform to an extremely high level.

A Review Qualification:
  • One thing that became apparent over the course of the reviews of the KLEI gZero and KLEI Harmony®Plug product lines from KLE Innovations, was the impact good power cables has on system performance.
  • To get the very best out of your system and these cables you need good power cables
  • If you try the KLEI gZero cables and feel that they do not perform to the levels I have observed in these reviews I would urge you to try some different power cables.
  • There are several posts on this blog that may assist you

My Review System:

  • Custom turntable with Denon DL103(modified) phono cartridge on and Audiomods Arm with one piece silver litz cable

  • Simaudio MOON LP5.3 RS phono stage

  • Schiit Bifrost USB DAC with UBER analogue upgrade

  • NAIM 5i integrated amp (has a passive pre-section)

  • Gershman Acoustics Sonogram speakers

  • the KLEI gZero6 Interconnect and Speaker Cable products

page6_blog_entry55-page6_blog_entry52-page6_blog_entry40-two-thumbs-up-2 A highly recommended product!

KLEI gZero6 Interconnect Cable Review

Pasted Graphic

The KLEI gZero6 Interconnect from KLE Innovations is their current top-of-the-line (TOTL) offering.

Not only is this their current TOTL Interconnect, it is fitted with their TOTL
KLEI Pure®Harmony RCA connectors.

Having just completed a review of the
Pure®Harmony RCA connectors attached to my own Stager Silver Solids Interconnect cables (see KLEI Pure®Harmony RCA Plug Review), I was very interested in hearing what improvements the "gZero" cable architecture of these cables would achieve.

The principal of the
"gZero" cable architecture is - and I quote from their web site...
  • In accordance with KL’s Signal/Ground Formula, the KLEI gZero architecture is comprised of hand wound conductors, and implemented in a manner to dynamically enhance electron flow in the Signal conductor, without the use of electronic components”
  • Each successive model in the KLEI gZero range, utilizes a progressively more complex and sophisticated cable architecture, employing varying combinations of multiple neutral/ground conductors, constructed from ultra high conductivity copper and/or silver.

in very simplistic terms, they are winding one or more neutral conductor(s) around the signal conductor!

This is a very different approach from many cable companies, in that many companies (not all) go out of their way to keep the signal and ground conductors exactly the same length and normally parallel to each other.

The purpose of this type of architecture? - again from their web site -....
  • The KLEI gZero architecture dynamically works to maintain a zero voltage Ground state”
Very Interesting - they endeavour to maintain a zero-voltage Ground state (reading between the lines - no noise!) - this would also prevent noise contamination into the circuitry of any of the connected components also.

I believe there are some people out there that may challenge the
“validity” of the gZero™ circuitry developed by Keith Louis Eichmann (aka KL), probably due more to a “belief” rather than actual empirical evidence!

The old “World is Flat” syndrome Happy.

At this point I'll refer you to their web site for more technical details if you are so inclined - I've already read it Happy...


OK - Enough of the Technical Blurb...

So, I set about comparing the performance of two 1 meter interconnect cables...

  • both having the very same KLEI Pure®Harmony RCA Plugs attached
  • each, in turn, connected to the very same components and allowed to burn-in
  • both reviewed in the same system - nothing else was changed
  • one interconnect utilizes a solid silver conductors of a twisted pair architecture
  • the other KLE Innovations gZero architecture, conductor material unknown, but I assume it’s very high quality copper

So - I know conductor quality is significant, but I believe it’s more about the cable architecture employed!

On To The Findings...

Bass Performance...

  • On the very first track played with the KLEI gZero6 Interconnect, I could tell there was added depth to the bass frequencies.
  • The bass was not bloated, as in "more bass", but the bottom end had extended to encompass lower frequencies than my own interconnects were capable of delivering. This was especially apparent on tracks with very low synth work and on tracks featuring pipe organs
  • the bass was also extremely well controlled, such that instrument specific textures in the bass register could easily be discerned.
  • How much difference was there? - I would compare it to getting new speakers with a larger bass driver! - yes, that much!
  • The "speed" of these two interconnects were very similar - hardly surprising considering the quality of materials used
  • Both exhibited extremely fast response to transient peaks - e.g. drums, rim shots, tambourines and cymbals responded in the same manner using either interconnect
  • Piercing guitar chords and brass instruments (mainly trumpets and trombones) had almost identical qualities
  • It was in the finer micro details of cymbals, tambourines and triangles that the the KLEI gZero6 Interconnect nudged into the lead.
Details and Clarity...
  • Here, the KLEI gZero6 Interconnect edged further ahead, partly because it sounded a little more detailed, but it was more than that…
  • In orchestral tracks there was better isolation of instruments across the board, e.g. violin and viola when playing the same notes are often difficult to distinguish, but now the viola had additional depth which now distinguished them more from the violins
  • There was an added warmth and fullness, or “body” across the entire frequency range which made large orchestral works appear smoother and much more enjoyable
  • There was more texture in individual instruments e.g. you could easily discern the drum skin on large orchestral bass drums vibrating – it had more texture to the rumble following the the initial strike, rather than a simple boom and wind instruments like the Oboe and Basoon had a more realistic conveyance of their individual timbres.
  • There was smoothness in the upper register of violin soloists - even Itzhak Perlman sounded mellower, even on his more vigorous pieces!
  • The KLEI gZero6 Interconnect revealed more in the area of micro details, such as the reverberation of instruments with a venue
Image and Spatial Integrity...
  • Again, the KLEI gZero6 Interconnect pulled ahead, serving up a wider and deeper image on those tracks subject to the most finicky of sound engineers.
  • The separation of instruments was more pronounced due to their pin-point placement and what is often referred to as "more air" around each instrument
  • The image also extended further forward to go beyond enveloping the listener, it was more like “immersing” the listener in the performance.
  • I didn’t witness any difference between the two cables on my system, both were exceptionally quiet
  • but, on another system the KLEI gZero6 Interconnect proved to be significantly “Blacker” than the very well respected Interconnect cable it replaced.
In Summary…

KLEI gZero6 Interconnect
  • Extends the range of the bass to very deep low frequencies with control.
  • Expands the image in three dimensions completely enveloping the listener, but it also separates the musicians/artists/instruments within that image by improving their individual spacing.
  • Clarity and details are significantly enhanced – perhaps in part due to the improved image.
  • Dynamics are lightning fast across the entire frequency range, But there is also an element of smoothness, particularly with violins and soprano, which can be quite shrill with other cables.
  • They are warm and full bodied – in essence, more complete.
  • They convey a very realistic sense of being “immersed in the venue”.
  • They are very quiet.


All of the above
"performance metrics" are well understood in audio circles and easily discernible.

But there are other "attributes" that are more of an “
ethereal nature” that is often more relevant to a musical performance, such as warmth, full bodied, richness, emotion etc...

These are observed at the time of playback and although, often as a result of technical/design improvements, they are more subjective and far from measurable - unless you are going to “
count the number of goose bumps” experienced Happy

One KEY factor…

The abilities of the system being used to evaluate the performance

My System…

  • is a modestly price system by today’s standards - e.g. there are many components these days cost more than my entire system.
  • From that perspective, I realize my system may not be “All Revealing” with respect to the considerable abilities of the KLEI gZero6 Interconnect - I believe they are capable of so much more.
  • But, in my system’s defence - it has some killer power cables which elevate its dynamic and spatial performance to systems costing many times its modest price.

Even though the KLE Innovations products worked exceptionally well on my system, I have since had the opportunity to hear them on what many would consider
“a system of higher resolving abilities”, the heart of which is a Gryphon integrated amp into Magico V2 speakers.
  • I was not surprised to find they also performed extremely well here, providing a spacious and very dynamic performance with a smoothness that made music from all genres that much more enjoyable.

In Short…

The Stager Silver Solids +
KLEI Pure®Harmony RCA's - $150 + $140
  • achieved an extremely high level of performance
  • For many albums the differences were discernible in only one or two of the above "performance metric" categories
  • However, they fell a little short in bass response and exhibiting attributes of a more ethereal nature.
  • KLEI gZero6 Interconnects - $565 (AUS)
  • Was the top performer - enough said!

Even though the
KLEI gZero6 Interconnect demonstrated its technical prowess across the board, it also delivered an exceptional "ethereal performance", having more warmth, body and emotion than my own interconnects, which, for me, translates into a much more enjoyable performance without any fatigue.

For those of you lucky enough to have a high resolving system, then it's a no-brainer - the
KLEI gZero6 Interconnects should be at the top of your Christmas List Winking

For the rest of us, we have to wrestle with the prospect of living on Hot Dogs for a couple of months. Happy

KLEI gZero6 Interconnects will not break the bank i.e. compared to much of their competition, but selling-off some old gear should expedite their arrival Happy


So you may be wondering what the acoustical difference there is between the
KLEI gZero6 Interconnect and it’s “little brother” the KLEI gZero3 Interconnect.
  • First let me state: the KLEI gZero3 Interconnect is an extremely adept interconnect.
  • It will outperform many other well respected cables and
  • it’s nobody’s “little brother”, just a more affordable member of a very good product lineup.
  • The tonal quality of both cables is exceptional and consistent, delivering a very neutral and very controlled performance.
  • the KLEI gZero6 Interconnect just has a little more depth and adds a dash of “soul”.

Having said that, perhaps the best way I can describe the difference…
  • – it’s like changing from a 40” TV to a 60” TV, both having identical technical specs
  • Everything is just bigger, clearer and that much more enjoyable!


The KLEI gZero6 Interconnect now utilizes the latest advances in KLEI gZero Architecture/Technology
Providing significant improvements in performance.

For details please see...
KLEI gZero6, gZero10 and gZero20 IC Product Update.

My Review System:

  • Custom turntable with Denon DL103(modified) phono cartridge on and Audiomods Arm with one piece silver litz cable
  • Simaudio MOON LP5.3 RS phono stage
  • Schiit Bifrost USB DAC with UBER analogue upgrade
  • NAIM 5i integrated amp (has a passive pre-section)
  • Gershman Acoustics Sonogram speakers

page6_blog_entry52-page6_blog_entry40-two-thumbs-up-2 A highly recommended product!

KLEI Pure®Harmony RCA Plug Review

Over the last few weeks I’ve had a chance to become accustomed to the tonal qualities of the KLEI Silver®Harmony RCA Plugs that were installed on my Stager Silver Solids Interconnects for the KLEI Silver®Harmony RCA Plug Review, but those interconnects were now the pipeline from my Simaudio Moon LP 5.3 RS phono stage to my Naim 5i integrated amp, the source being a modified Denon DL103 cartridge attached to an Audiomods Classic tonearm having a one piece silver litz cable.

As such, I have come to appreciate their extraordinary abilities of these RCA connectors, which includes extremely fast response to not only very fast highs generated by percussive instruments such as cymbals and tambourines, but also their superb control of bass details such as those generated by pipe organs and synthesizers.

Also, the image that the
Silver®Harmony RCA Plugs convey is wide, deep and very precise. But perhaps the best quality of all - they are very “spacious”.

What do I actually mean by “spacious”? - In this case, it’s the ability to convey the space around the musicians and the subtle reflections of sounds from of their instruments within the recording venue.


KLEI Pure®Harmony RCA Plug represents the pinnacle of the KLE Innovations Harmony®Plug range of RCA connectors and as such, should provide the best performance.

Their appearance is almost identical to the
KLEI Copper®Harmony and KLEI Silver®Harmony RCA Plugs except for the mauve colour of the logo stamped on the collar. But inside, the centre pin and neutral pins are made of solid silver in accordance with KL’s Signal/Ground formula, giving them an IACS conductivity rating of 106%

But I still had to wonder, after becoming accustomed to the already exceptional performance of the KLEI Silver®Harmony RCA Plugs which, due too its solid silver neutral conductor and the extra thick silver plating on the copper centre pin, has the same 106% rating. Exactly what was left to improve upon?

Thanks to the guys at KLE Innovations, they had saved me considerable time by sending a set of
KLEI Pure®Harmony RCA Plug which had already undergone the 150-200 hours burn-in normally required from new, so that period of time had now been reduced to around 24 hours hours.

Whilst waiting for the RCA’s to arrive I had selected several albums from my collection of vinyl which I thought might best demonstrate the improvements the
KLEI Pure®Harmony RCA Plug should bring to the party.

Since KLE Innovations is located in the “Land of Aus” (Oz) (aka Australia), what better album to select than
Business as Usual by Men at Work. The sound engineering on this album is superb. Details, such as the high frequency edginess of the the Sax and the crispness of the drums and guitar work to the more subtle changes in the textures of the various bass lines on the various tracks made it a very good album for the evaluation.

In very simple terms…
Everything got bigger, faster and cleaner!

The bass line now had added detail and texture, the cymbals were crisper and fuller, the mids were warmer, the dynamics were faster and the image just seemed more complete. There was an added “punch” to both the percussion and also to the hammering of the very muted guitar strings. Lastly, the vocal detailing is now very clear and very well isolated within the recording.

Songs from the Wood, by Jethro Tull, an album from my long distant past, has always been a favourite. It features some of the best harmonized and multi tracked vocals ever put onto vinyl. It was these vocals that the KLEI Pure®Harmony RCA Plug seemed to perform minor miracles with micro details, in order to separate each vocal into a clearly audible presentation.

For me, spatial integrity, i.e. how accurately the artists and instruments are represented in the space of the recording venue, is best portrayed by classical recordings, since most are recorded using very few microphones, which translates to less manipulation of the final product.

To this end, one of the best albums is from a bunch of very anal sound engineers that record on the Tacet label.

How anal you ask?

  • Side Two on the album Das Mikrofon Vol.II, contains 24 tracks, each track using a different microphone!
  • Side One contains some nice Jazz Happy

But it was Das Mikrofon Vol.I that I had selected to determine just how good the Pure®Harmony RCA Plug was at conveying some very large venues.
  • Track One on Side Two is Toccata Terzza in A, one of my favourite pipe organ tracks that I also use to determine how just well bass frequencies are reproduced, since with pipe organ music there are extremely complex low frequency textures produced by those massive pipes.
  • Not only did the KLEI Pure®Harmony RCA Plug convey the cavernous nature of the venue, but they displayed extremely fine control across the entire range of pipes from the smallest high pitched pipes to the low frequency behemoths.

How many albums/tracks can I list where the
KLEI Pure®Harmony RCA Plug made me sit up and listen? Pretty much all of them.

There are a few tracks where the improvements were more subtle…
  • such as the whispery textures of Diana Krall’s voice on her tribute to Nat King Cole album All For You.
  • The distinctive sound of the slide of a bottleneck on guitar strings of Ry Cooder on his album Boomer’s Story

Then there were improvements that leapt off the vinyl - the all-out in your face dynamics on albums such as..
  • the incredible percussion detailing and synth work on James Newton Howard & Friends - by James Newton Howard
  • some really deep synth and piecing guitar work on Under the Joshua Tree by U2
  • the explosive “rifle-crack” drums and excellent synth work on Back In The Highlife from Steve Winwood
  • the crispness of the guitar work on the album But Seriously Folks from Joe Walsh
  • And if you are a fan of Led Zepplin’s - Whole Lotta Love - you’ve never heard it like this - incredible!


Well, as I said above, while waiting for the
KLEI Pure®Harmony RCA Plug I wondered just what improvements would they provide. Was it going to be a serious case of “diminishing returns”?

The improvements I witnessed between my identical interconnects, one se
t with the KLEI Silver®Harmony RCA Plug and the second with the Pure®Harmony RCA Plug was immediately noticeable. Improvements in dynamics, clarity, image and bass extension, with a new “fullness” to the reproduction and a new “reality” in the performance.

I’ve experimented with cables of several types over the years and used a variety of connectors, including the Eichmann Silver Bullet, which I had rated very highly.

Then Keith Louis Eichmann requested I try his new
KLEI Copper®Harmony RCA Plug which performed even better. The KLEI Silver ®Harmony RCA Plug again proved to be a significant improvement over the Copper®Harmony, but the level of performance the KLEI Pure®Harmony RCA Plug has achieved is the new benchmark in RCA connector performance.

Achieving this level of performance simply with an RCA connector may sound unbelievable, almost “magical” and in my mind, makes the team at KLE Innovations…

“The Wizards of Aus”

If you like to dabble with making your own interconnect cables, then the
KLEI Harmony®Plug range of products are designed to fit your budget and perform exceedingly well.

The one thing the KLEI Harmony®Plug range is not...


There is no gold or rhodium plating, no carbon fibre casing, no cryo treatment

If you are after looks - select another product


If you want a serious product capable of the ultimate in RCA performance….

  • KLEI Pure®Harmony : pure genius, pure performance, pure magic!

page6_blog_entry52-page6_blog_entry40-two-thumbs-up-2 A highly recommended product!

ADDENDUM: especially for Turntable Enthusiasts - also see UPDATE: Pure®Harmony RCA Plug Review