Home / Reviews / KLEI™Pure Harmony plugs (used as a Digital/SPDIF) by Willy Low (AV2DAY.com)
KLEI™Pure Harmony plugs (used as a Digital/SPDIF) by Willy Low (AV2DAY.com)

KLEI™Pure Harmony plugs (used as a Digital/SPDIF) by Willy Low (AV2DAY.com)

The next generation Eichmann Bullet plug design

I last raved about the KLEI™Copper Harmony plugs sometime ago, and felt like they were the bee’s knees for what little outlay they require to purchase. I used the Copper®Harmony plugs, along with 0.5 meter of Furutech FC-63 cable stock for an ambitious low cost, high performance co-axial cable, to transmit digital signals between my Theta Pearl CD transport to the BDA-1 DAC. It was a gem of DIY cable find.

I was happily minding my own musical business when an e-mail from KL (Keith Louis Eichmann), the very man who started the Eichmann revolution in RCA plugs, asking me what my plans are with the 0.5 meter Furutech cable stock remaining which I had had initially planned to mate with a pair of Neutrik Profi connectors for comparison purposes, but some how never got around to doing so because I was super satisfied with the KLEI Copper Harmony plugs. KL suggested that I use the extra 0.5 meters on his flag ship KLEI Pure®Harmony plugs instead. I agreed and within the next 3 weeks or so, a 4pack of KLEI Pure Harmony plugs arrived in to my post box.


I raved about how easy it was to work with the KLEI Copper Harmony plugs and the KLEI Pure Harmony plugs were just as easy to terminate, due to the same smart V-shaped terminal design, for easy soldering. The KLEI Pure®Harmony looks and feels exactly the very same as with the KLEI Copper®Harmony plugs as I put them together side by side. I bet if I had mixed them up, it would be near impossible to tell the difference, except for the colour of the KLEI Logo and the KLEI Copper Harmony plug had a more matt coating finish to the connector pins. The KLEI Pure Harmony plug’s pins were a little more brilliant satin finish by comparison. Read about the DIY work in detail on my previous posting of the Copper Harmony plugs dated 2nd April 2014, other wise carry on.

The Sound

In comparison to the KLEI Copper®Harmony plugs, the KLEI Pure®Harmony offers wider dynamic range and bandwidth. In comparison, the Copper plug may sound a little rolled off on the extreme high end, causing the Pure plug to sound more airy and 3D in sound staging (the air between the musicians is phenomenal). The KLEI Pure®Harmony plug also sounded a little cleaner in the bottom end, although this can sometimes be mistaken as leaner by less experienced listener, or in less capable systems. The mid range has the same roundness, and robust quality for fully fleshed out imaging. The KLEI Pure®Harmony plug is even more transparent than the already superb KLEI Copper®Harmony plug, letting through more minute detail in the music mix. In most other aspects, the same familiar sound of the KLEI Copper®Harmony plug is carried over wholesale.


If one is willing to go all the way, and spend a little more $$$, my sincere advice is to go for the best KLEI Harmony plugs to satisfy one’s upgrade crave, once and for all. The KLEI Copper®Harmony plug is great value, but the KLEI Pure®Harmony plug offers excellent sound quality with little or no compromise in sound, all packaged in an understated form. After all if cables are mostly plugged in to the back of the HiFi equipment, who needs “bling” in back alley?


One comment

  1. Realize the Organic Realness in the Musical experience, with KLEI 🙂

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