KLEI Pure Harmony RCA

KLEI Pure®Harmony RCA Plug - Turtable Review

If you’ve read the reviews of the KLE Innovations products on this site, it should be no surprise that I would at some point in time get around to installing the KLEI Pure®Harmony RCA Plug onto the one-piece silver litz loom installed in my Audiomods tone-arm that supports a Denon DL-103 moving coil cartridge.

Pure Harmony RGB
Turntable Background:

My Turntable started its life 32 years ago as a Rega Planar II, but over the years, after applying a series of modifications and upgrades (please see Turntable Mod's and Denon DL 103 Tweak for details) it has been transformed into a device with outstanding performance characteristics.

The only things left over from the old Rega turntable is the lid and the on/off switch.

Call me sentimental. Happy


The installation of the KLEI Pure®Harmony RCA Plug was very simple; the most difficult part of the operation was removing the stock RCA plugs, which had a crimped cable strain relief, but soldering the extremely light gauge wires was a doddle, thanks to its redesigned signal and neutral tabs.

Once installed, all that was left to do is burn them in - for 200 hours –
c’mon KL, really?

That’s an awful lot of exercise, finding an album, changing sides, putting them back on the shelf. No wonder audio streaming is getting popular. Gasp

But in reality…

Well, 200 hours may be the optimal burn-in time recommended by KLE Innovations for ultimate playback quality to prevail.

However, for this particular application, it appears you don’t have to wait that long for some really mind blowing improvements to be heard from your treasured analogue rig.

Initially, the
KLEI Pure®Harmony RCA Plug has a tendency to be a little bright and more than a little edgy, at least on my system. It took around 20 hours for that to settle down and transform into a very smooth and incredibly detailed performance. Which was nice, because with 180 hours left on the clock, I was giving some serious thought to installing the RCA’s onto an interconnect and letting my streamer and DAC complete the burn-in process – a much less time consuming approach.

At around 30 hours I became very impressed with the performance improvements.
  • Dynamics were very fast and extremely crisp.
  • The image is deeper than before, but there is more spacing between the instruments both left to right and front to back, e.g. each “section” in the orchestra (i.e. violins, violas, cellos etc.) have significantly more width to them.
  • The timbre of instruments having more details sounded even more natural
  • The venue acoustics are outstanding and really immerse you into the performance
  • The improved clarity in complex orchestral tracks allowed them to be played louder without distortion – 1812 with digital cannons anyone?

But the one outstanding quality of the
KLEI Pure®Harmony RCA Plug was their transmission of incredibly fine micro-details that seemed to bring a “new reality” to my vinyl collection, especially some older live recordings.

It was apparent on the very first track I played,
Baby Please Don’t Go from the 1973 album Better Days by Paul Butterfield, featuring Ronnie Barron, Amos Garret, Geoff Muldaur, Christopher Parker and Billy Rich.
  • I dropped the arm and was returning to my chair, but I never made it. As soon as the track started playing I spun around to listen more intently, standing, the sound so totally different from any previous plays.
  • The extremely fine details of the bottleneck sliding on the strings was just downright eerie, like a ghost from the past. Many tracks sounded as though they were recorded in a gospel hall with two mikes and a stereo reel-to-reel. The natural reverberations are melded superbly with the musicians and their vocals and then reproduced in my system with a haunting reality.

For me, this was a complete jaw-dropper. I’d heard some very expensive systems that may have approached this level of reproduction, but I never expected my current configuration would be capable of such a refined and detailed presentation.

And all this was due to the KLEI Pure®Harmony RCA Plug? - You got it!

Some other albums that grabbed my attention, mainly because of the amazing reproduction of those extremely fine details include…

  • The Doctor, by Doc Powel - with his beautifully mellow jazz guitar, piano, drums and bass. But the outstanding instrument for me was the superb reproduction of the drums, especially the cymbals. Again, the reproduction of the natural reverberations from within the venue is a significant contribution to the reality portrayed.
  • Songs From The Wood by Jethro Tull (1977) – I’ve mentioned this album in previous reviews, where I found the vocal harmonies to be the most profound of Tull’s “signature sounds”, but after installing these RCA’s the reproduction of those vocals to this level of detail is astounding.
  • Boomers Story, by Ry Cooder (1972) – again, I ‘ve mentioned this album in previous reviews and again I mention the superb reproduction of his use of the bottleneck.

What’s a Bottleneck?...
  • A “bottleneck” is a tube of glass or metal that the musician slides on the strings over the fretboard.
  • Why am I so enamoured by this particular sound?
  • Having played guitar for over 40 years, many of which were spent dabbling in the art of Delta Blues, provides one with first hand experience of the very distinctive sounds the bottleneck makes,
  • e.g. just the vibration of the strings against the bottleneck when simply sliding it up the strings is a detail seldom reproduced in a believable manner.
  • But when it is - goosebumps! Happy

Moving forward a few years …
  • LEGEND: The Best Of, by Bob Marley and the Wailers (1984) – whilst not really in the same league as those above for it’s natural venue acoustics, the studio tracks are extremely well engineered and yields the widest image of my entire collection) – which now exceed the width of the speakers by a couple of feet.
  • Down to the Moon by Andreas Vollenweider (1986) – again – not a really natural sounding album, but exceptionally well-engineered. The outstanding feature of this album is it’s micro details and associated dynamics, i.e. those little details you hear when strings are plucked, like the fingernail catching the plucked string – as with a Harp. This album brought Harp music to the mainstream back then, but it has never lost it’s appeal and now with the vastly improved reproduction it can be enjoyed all over again, like a new album.
  • Raising Sand by Robert Plant and Alison Krauss (2007) – for me, this was one of those albums you regret buying. You know, you get it home and it just doesn’t do anything for you. But it stayed on my shelf, seldom played. Well, that was until I started to audition the KLE Innovations product line, after which the album perked up and things started to gel. It seems that before installing KLEI products I was missing so many details in many of my recordings. In this case the album sounded lackluster and had no excitement – not any more, it reproduces extremely fine details and vocal textures from these two exceptional artists are outstanding.

One last artist that really presents a challenge to any system, particularly where clarity is concerned, is Mike Oldfield, remember
Tubular bells? There’s also Omadawn, and Five Miles Out among others. But the one thing they all share is big sound, lots of multi-tracking instruments and incredible details, a lot of which can be lost. Well not any more – with the KLEI Pure®Harmony RCA Plugs in the system those details shine through with scintillating glockenspiels, astounding tubular bells, crisp distorted guitar licks and airy background woodwinds – absolutely stunning.

I haven’t mentioned any classical recording, mainly because it would lengthen this review considerably. However, it is worth mentioning that the
KLEI Pure®Harmony RCA Plugs conveys a reproduction where the venue in many orchestral tracks appears as cavernous as the actual space it was recorded in, with a precise placement of musicians in the overall image and a clarity that completely exceeded my expectations from such a simple RCA upgrade.

And the Pricing?

A set of the
KLEI Pure®Harmony RCA Plugs cost around US$120 for a set of four, but the improvements made in my system on this one component was as significant as replacing the cartridge costing substantially more than that, making it an extremely attractive investment.

What do you do with the two remaining plugs? – you find an analogue buddy and you blow his mind as well.

KLE Innovations actually sell a six pack for AUD$185 – so you could convert your turntable and upgrade the RCA’s on the interconnect from the phono stage to the amp

I’m not really sure why they don’t offer two packs just for this purpose, particularly on this model – perhaps they will reconsider after reading this review


The most significant improvement the
KLEI Pure®Harmony RCA Plugs made for me was the reality that is now conveyed, which is one of those ethereal qualities that is so hard to measure and even more difficult to describe. It is also subject to our own experiences.
  • The greatly improved reproduction of venue acoustics from my system following this particular upgrade, often triggers memories of my own experience of playing in bands in many different locations, from small village halls, to nightclubs, to medium sized venues, each with their own very unique acoustic signature.

The Denon DL103 moving coil cartridge has been around for a very long time and at $229 it is a steal. There are a couple of minor warts and there are a few outfits than can modify this cartridge to get it to perform much much better. But before you opt to have the cantilever replaced, or have the cartridge “nuded” or have it mounted into an alloy or wooden head-shell, try this modification first. You will be amazed by the improvement in detail and you don’t have to wait the 6-9 weeks that the other options will take.

The 200 hours burn-in time appeared to me to be substantially shorter and I have not heard any improvements in performance since around the 60 hour mark. That may be due in part to the WBT high content (4%) silver solder I used, which I have found to perform extremely well when installing the
KLEI Pure®Harmony RCA Plugs onto my interconnects also.

If you consider implementing this tweak, I would also strongly recommend for the phono stage to amp connection, either the
KLEI Zero3 Interconnect , or better still the KLEI ®gZero6 Interconnect to compliment this change, since together, they will provide the best possible pathway from cartridge to amp you could possibly have.

My Review System:

  • Custom turntable with Denon DL103(modified) phono cartridge on and Audiomods Arm with one piece silver litz cable + KLEI Pure®Harmony RCA’s

  • 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-2This is definitely a “MUST HAVE” for turntable arms having a one piece continuous loom!

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