Maximizing the potential of headphones

Guo Hancheng - Original text and photos

Note: This version is a translation of the original article.

How to fully realize the potential of headphones? Headphone amplifiers are usually the fastest route to firmly controlling the headphone unit with enough power, but once you've solved the headphone drive problem, the next upgrade is likely to be the headphone cable. The Duet headphone cable from Crystal Cable in the Netherlands, the first product from Crystal Cable Portable, certainly deserves attention.

portable duet

Portable Cable
The Duet is not the same as the Crystal Cable we know, but the technology inside is the same. Crystal Cable's audio cable, like its name, is almost always transparent, using a coaxial construction, and the conductor is the signature gold and silver alloy. It has a thin layer of high-strength PE material to reduce the resistance of the cable. With Duet, however, there is a slight variation. The conductor is still the signature gold and silver alloy, but the appearance is black and white, with a braided winding, and the outer jacket is made of medical grade plastic, which is soft and durable for mobile listening.There is also a Crystal Cable decoration in the center of the headphone cable, which is marked with the original serial number for verification.


Diversified headphone jack specifications
Although the Duet is a headphone cable, the terminals can be changed to RCA terminals. Depending on the headphone jack, Crystal Cable also offers corresponding terminal options. I got my hands on the IEM MMCX terminal - you can also buy the IEM 2-pin, 2.5mm TS, 3.5mm terminal, these are common standard terminals. Crystal Cable also offers the Lemo terminal for Focal Utopia, HD800 terminal, and the Mini-XLR 4-pole terminal for Audeze. As for the terminals to connect to the source, Crystal Cable has a wide variety of options as well, including 2.5mm, 3.5mm, and 6.35mm standard headphone jacks, and the choice of balanced jacks is also extensive, including the new 4.4mm specification, 4-pole XLR, or dual 3-pole XLR.

It's dazzling, isn't it? If you're an HD800 user, just buy the HD800 terminal, they take care of both Focal Utopia and Audeze users. If you need to balance the output, Crystal Cable can build it to suit your needs.

Diversified headphone jacks

Transparent, bright and wide bandwidth
I got the Duet headphone cable with a standard 3.5mm headphone jack, using Japanese Oyaide high end parts, and a standard MMCX in the headphone section, with two headphones on hand to match, an Acoustune HS 1551 CU, a Sony Just Ear XJE-MH2 custom headphone demo sample, and Sony's own Kimber Cable headphone cable to match.

The original Sony XJE MH2 (I'm listening to the Listening version) comes with the original headphone cable, which obviously lost in the first round, so if you're going to order the XJE MH2 custom headphones, the upgrade cable will be obvious . As for Acoustune's headphone cable, Sony's Kimber Kable headphone cable and the Duet, all three have their own benefits, and the Duet does have its own distinct sound signature.

What kind of sound features? Deeper low frequencies, more transparent mid-high frequencies, cleaner and faster music transients! But I'm not saying Duet beat out the other two headphone cables, but rather that Duet's personality is sharp in these three sections; Acoustune and Kimber Kable are both twist braided cables, with Acoustune being the thickest, Kimber Kable the thinnest, Duet sandwiched in the middle, Acoustune having the most low-frequency feel, rock atmosphere the highest, Kimber Kable range balanced and sounding soft and smooth , and Duet winning in tonal clarity. That's why I say that each of the three lines has its own merits and the sound direction is different.



The sound transparency is immediately audible
If you have a high demand for sound transparency, then the Duet might be your cup of tea. For example, the Japanese jazz recording "Misty" by the Three Blind Mice is auditioned with Duet and Acoustune HS 1551 CU headphones, and it's obviously better than the original cable that came with it. The sound is also brighter, with the brushes brushing against the ear, and Duet reveals the beauty of the recording. When I replaced the HS 1551 CU with the original cable, the thickness of the low and mid frequencies was better, but the vibrancy of the high and mid frequencies was slightly less than that of the Duet.

I don't want to say which cable is better, because each has its own advantages, and the choice depends on your taste in music: Duet is good at showing the tension and vividness of music, while the HS 1551 CU's original cable has a good sound thickness, full and thick in the low frequencies, and Kimber Kable's voice wins out with balanced sound, soft and smooth. Each of these three cables excels, but the tone and taste of the expressive music is slightly different.

Three Blind Mice


Complementing the gorgeousness of the mid to high frequencies
The HS 1551 CU's sonic tonality is quite strong in the low and mid frequencies, and with Duet behind it, the mids and highs add a touch of grandeur to the sound. Like listening to Bill Evans' "Waltz For Debby," "My Foolish Heart", because it's a live recording, and there's a fine-grained bistro background noise behind the jazz, which you won't miss when paired with Duet, adding to the warmth of the live recording. Listening to it with the original line, the instrument is larger in shape and thicker in sound, and the background cup shake staggered detail is slightly further away and interesting. However, if you like bright, quick and rich musical details, then Duet will certainly not disappoint you.

Waltz For Debby

Duet's low frequencies take a clear and fast path, with no hitch and a natural extension of the low frequency dive. When listening to the "Tricycle" album, the electric piano starts the intro, followed by the blasting jazz drums, Duet's blasting low frequencies with a clear sense of speed, full of impact, the electric bass is full and powerful, the notes are clear , the bass Solo's phrasing technique is gorgeous. With Duet's clean and clear low frequency performance, you can clearly hear the Bass player's superb technique.


With Richie Lee Jones' "Pop Pop" album, the soundtrack "Spring Can Really Hang You Up Most", the nylon guitar starts the intro, Duet shows a clean strumming line, while Richie Lee Jones' vocals are light and sweet with a lazy, guttural sexy expression, it's fascinating to listen to with Duet, Duet's low frequencies are well resolved, you can't mistake Double Bass for electric bass, because of the subtle hairy edge of the Double Bass strumming, and the natural volume decay after the Double Bass strumming, the detailed low frequencies are full of beefy tendons, instead of electronic flavor.

Pop Pop

Classical Music Verified Quality Enhancement
For classical music lovers, Duet's transparent and natural mid-to-high-frequency performance is a definite upgrade. I was at a music talk talking about the slow movement of "Chopin Piano Concerto No. 2," using Pierce's version, and I listened to it on a HS 1551 CU with Duet headphone cables. The piano's rhyme extends beautifully, and the theme repeats itself in high octaves after the theme is repeated, making the piano appear gorgeous and romantic.

Wait a minute, let me compare with the version of the new Chopin Piano Competition winner, Avdeeva. The orchestra is an eighteenth-century orchestra (retro), and the sound is not as gorgeous as the Royal Philharmonic Orchestra with Piers, which is relatively rustic and dense, but Avdeeva's piano is a romantic mastery of speed.

What kind of speed is called romance? The music of Duet's headphone cable's vivid music analytic power has made me devote myself to Avdeeva's romantic feelings, and I can't help but admire this Chopin Piano Competition winner. What a well-deserved name!

Chopin Piano Concerto No 2

A good choice for bandwidth, speed, and detail

Duet is Crystal Cable's first adventure into the headphone market. While they've already made a name for themselves in the home audio market with their gold and silver alloy and coaxial cable construction, their first offering to the new market is a highly finished headphone cable. The Duet is clearly a headphone cable with a personality, and for music lovers who are looking for details, lines, bandwidth and speed, the Duet is an upgrade cable worth trying.

Duet Presentation

Original text (in Chinese)  


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