Harmonic Technology Digital Copper III 50Ω cable
Feb 23, 2023 20:21:58 GMT
John, MikeMusic, and 4 more like this
Post by MartinT on Feb 23, 2023 20:21:58 GMT
Harmonic Technology Digital Copper III 50Ω cable
The US sourced HT is the only cable I can think of that is manufactured specifically as an audio grade master clock cable, not a general purpose S/PDIF or similar. It really ought to be good at its one job, then!
The HT has two claims to greatness as follows:
All this bodes well for excellent performance with maximum resistance against intrusive EMI/RFI noise. The cable is finished in an attractive translucent dark red PVC jacket. HT specifies that crimped connections must be used in order to preserve its performance. In HT’s words, “Harmonic richness is greatly increased due to the elimination of crystal boundaries and impurities that can disrupt the integrity of the complex harmonic digital waveform. A velvety-black background is also highlighted, such that small details appear to be holographically suspended in the soundstage.” They then go on to say “Since copper has a slightly “rich" sound, with added bass and slightly less treble detail than silver, this copper digital cable will be a great match for systems that need more “sweetness" in the highs.” I don’t know about sweetness, the reason why I chose copper over their silver version is that I find silver often accentuates brightness, which is one thing I do not like with my revealing system. We shall see.
I bought a 1m length since I never received any replies to my enquiries about 0.5m lengths, which is what I needed. Thanks to HK Audio Accessory for the very swift despatch. I listened first to the cable as supplied and I then cut it into two and terminated the open ends with 50Ω crimped BNC connectors to make two matching cables. The first 100 hours of burn-in were with the cable as a single length and subsequently another 100 hours have gone onto the two separate lengths, both fed from AfterDark sinewave clocks. As I well know, clock cables can take an age to burn-in and just recently, I learned with the LMR-400 how it can open up and bloom a good few hundred hours into use.
For the purposes of comparison, I have my Belden 4694R and LMR-400, the two most recently used cables, standing by.
Listening to this cable (or, more accurately, the effect it has on the music) gives the impression of a smooth, grain-free presentation with a large soundstage, very focussed imaging and a lively, vivid sound. It’s detailed but not harsh, music is highly dynamic and the bass goes very deep while retaining attack. Sounds ideal, doesn’t it?
In comparison with the Belden, it’s considerably less bright in presentation, the Belden giving a slightly relentless feeling to the proceedings. It also has incredible structural bass, descending into impressive air movements with the right music. The presentation from the LMR-400 is much closer but the latter (cheap but giant killing) cable is a little less smooth and more grainy in the treble, ultimately hurting resolution. The HT has the best resolving high frequencies but remains smooth and grain-free. It has modest improvement in punch and tightness over the LMR-400’s already impressive bass department. All three have a very open, non shut-in midrange with good vocal qualities.
Some music examples: in Melissa Tallon’s Tell Me So, the opening vocal is less congested and grainy and the accompanying bass has more power in the deepest notes; in Keith Richards’ You Don’t Move Me, the percussion is stunningly dynamic; in Bonaparte’s Last Two Lovers, Jundt's voice is remarkably textured; in London Grammar’s Wild Eyed, the acoustic decay is immense and the grit in her voice at full pelt more noticeable. In Kate Bush’s Waking the Witch, the separation of elements in the busy waking sequence is remarkable; in SBTRKT’s Wildfire, the combination of percussion strike and deep bass while holding Nagano’s voice steady is wonderful; in Allie Moss’ Already Down, her voice remains, for the first time, the right side of brittle and later when the ground shaking bass starts, the hammer blows have real impact. Finally, in Christina Pluhar’s Folia, the ambience, air and natural decay surrounding the interesting array of instruments makes it sound more wonderful still. Oh, and that dulcimer!
With only 200 hours on the clock (!) I feel there is more to come. At around £50, it’s quite outrageously good value for the performance delivered. One of those finds that worked out ever so well.
The US sourced HT is the only cable I can think of that is manufactured specifically as an audio grade master clock cable, not a general purpose S/PDIF or similar. It really ought to be good at its one job, then!
The HT has two claims to greatness as follows:
- This all-copper model’s 57-strand core is manufactured from 7N purity single crystal copper (OCC), with 22pF, 0.46uH and 0.008Ω per foot (apologies for the imperial metrics). Its characteristic transmission line impedance is 50Ω (there is a 75Ω model too).
- It is triple-shielded with a braided OFC copper outer shield, copper-mylar foil intermediate shield and a conductive PVC inner shield.
All this bodes well for excellent performance with maximum resistance against intrusive EMI/RFI noise. The cable is finished in an attractive translucent dark red PVC jacket. HT specifies that crimped connections must be used in order to preserve its performance. In HT’s words, “Harmonic richness is greatly increased due to the elimination of crystal boundaries and impurities that can disrupt the integrity of the complex harmonic digital waveform. A velvety-black background is also highlighted, such that small details appear to be holographically suspended in the soundstage.” They then go on to say “Since copper has a slightly “rich" sound, with added bass and slightly less treble detail than silver, this copper digital cable will be a great match for systems that need more “sweetness" in the highs.” I don’t know about sweetness, the reason why I chose copper over their silver version is that I find silver often accentuates brightness, which is one thing I do not like with my revealing system. We shall see.
I bought a 1m length since I never received any replies to my enquiries about 0.5m lengths, which is what I needed. Thanks to HK Audio Accessory for the very swift despatch. I listened first to the cable as supplied and I then cut it into two and terminated the open ends with 50Ω crimped BNC connectors to make two matching cables. The first 100 hours of burn-in were with the cable as a single length and subsequently another 100 hours have gone onto the two separate lengths, both fed from AfterDark sinewave clocks. As I well know, clock cables can take an age to burn-in and just recently, I learned with the LMR-400 how it can open up and bloom a good few hundred hours into use.
For the purposes of comparison, I have my Belden 4694R and LMR-400, the two most recently used cables, standing by.
Listening to this cable (or, more accurately, the effect it has on the music) gives the impression of a smooth, grain-free presentation with a large soundstage, very focussed imaging and a lively, vivid sound. It’s detailed but not harsh, music is highly dynamic and the bass goes very deep while retaining attack. Sounds ideal, doesn’t it?
In comparison with the Belden, it’s considerably less bright in presentation, the Belden giving a slightly relentless feeling to the proceedings. It also has incredible structural bass, descending into impressive air movements with the right music. The presentation from the LMR-400 is much closer but the latter (cheap but giant killing) cable is a little less smooth and more grainy in the treble, ultimately hurting resolution. The HT has the best resolving high frequencies but remains smooth and grain-free. It has modest improvement in punch and tightness over the LMR-400’s already impressive bass department. All three have a very open, non shut-in midrange with good vocal qualities.
Some music examples: in Melissa Tallon’s Tell Me So, the opening vocal is less congested and grainy and the accompanying bass has more power in the deepest notes; in Keith Richards’ You Don’t Move Me, the percussion is stunningly dynamic; in Bonaparte’s Last Two Lovers, Jundt's voice is remarkably textured; in London Grammar’s Wild Eyed, the acoustic decay is immense and the grit in her voice at full pelt more noticeable. In Kate Bush’s Waking the Witch, the separation of elements in the busy waking sequence is remarkable; in SBTRKT’s Wildfire, the combination of percussion strike and deep bass while holding Nagano’s voice steady is wonderful; in Allie Moss’ Already Down, her voice remains, for the first time, the right side of brittle and later when the ground shaking bass starts, the hammer blows have real impact. Finally, in Christina Pluhar’s Folia, the ambience, air and natural decay surrounding the interesting array of instruments makes it sound more wonderful still. Oh, and that dulcimer!
With only 200 hours on the clock (!) I feel there is more to come. At around £50, it’s quite outrageously good value for the performance delivered. One of those finds that worked out ever so well.
