Test: the impact of a dc cable

The reason for this test is a comment from a reader. He shares his experience (in Dutch) with a DIY dc cable based on a certain type of cable from manufacturer Canare. It turns out that Ghentaudio, a Chinese manufacturer, provides an affordable, assembled product based on the same cable.

I ordered this cable to make a comparison with the standard supplied dc cable from the LHY power supply I use to power the DLink GS108 switch. The question is whether there is an audible difference, and if so, how big the impact is. This is not an exotic cable, so an interesting experiment within reach of a wide audience of audio hobbyists.

The costs

A one-metre cable, without additional insulation of the cable itself, is US$ 33.
Shipping costs are added and on the credit card EUR 35.49 is charged. On top customs clearance fees and Post NL charges of EUR 10.86 are added, bringing the total costs to EUR 46.35.

The power cable has been replaced before

The power cable supplied with the LHY power supply was replaced with an Essential Audio Tools ‘Current Conductor S’ cable several years ago. This brings quite a difference, which was surprising. There is much less restlessness in the soundstage, the soundstage becomes more insightful in the sense that placement of instruments and voices improves, and the treble in particular becomes significantly deeper in sound and less sharp. In other words, the knock-on effect on the final jitter in the conversion in the DAC is lowered.

It depends on the power supply how much of a change the power cable brings, but we replaced the power cable on several power supplies of different price categories in Haarlem and it is audible in all cases.

In case you are now thinking ‘yeah right, the power cable of the linear power supply that powers the switch and where the switch galvanically decouples the Ethernet cable, how far-fetched is that!’. My only answer to that is: try it out and judge for yourself. We do not all hear the same thing or appreciate a change equally.

The test

The Ghent audio cable was placed between the power supply and the switch for weeks. The switch is on 24 hours a day, so power is always running through it. I did not pay attention to changes in sound during this period.

Then 2 tracks were compared, first with the new cable and then the old cable was put back: the third movement from ‘Myths’ by Szymanowski for violin and piano and ‘Sky Blue’ by Peter Gabriel. Both are pieces with nuance and detail. You can listen to the tracks on this playlist.

With the Ghentaudio dc cable:

In this almost microscopic recording, the Szymanoski composition has a nice reverb. This is especially audible in the reclining piano chords that resonate for a long time with a lot of harmonic information.

Subtle is the sound when the side of the bow is stroked across the strings, giving you a ‘sighing’ sound. The high is nicely defined, while treble is the critical point in this recording. The grand piano creates sounds akin to skate riders (insects that can float on water with their legs) making circles on the water. The double tones of the violin lie nicely on top of the sounds of the grand piano.

In ‘Sky Blue’, the shaker is clearly placed at the back, just right of centre, in the soundstage at the beginning and sounds like grains of rice being moved in a wooden cylinder. The deep bass and powerful guitar chords at the beginning are rendered with much tone. All instruments are well placed and there is no unpleasant sound to be detected, courtesy of the AKM chip implementation by Eversolo in the Z10 DAC.

The harmony vocals of The Blind Boys of Alabama at the end give goosebumps every time. I got to see this live in Rotterdam and that memory was brought back again. The guitar chords under the vocals sound full, rich and clear.

With included dc cable:

The sounds of the violin and grand piano become harsher. It is not bad, but you can clearly hear the difference. The reverb ends a bit more abruptly, the sighing sound of bowing with the side of the stick is also less rich in timbre. It is louder and a bit more metallic in sound. The skate riders have been exchanged for a little boy throwing pebbles into the water.

With Peter Gabriel, the deep basses are much less prominent. They are there, but it sounds more like someone blowing into a big pipe; it is also a more droning sound in comparison, as if the control is somewhat gone. The guitar chords at the beginning are harsh metallic sounds; they lack tone.

The differences are somewhat magnified in the text of this review, but are quite subtle in the real world. It is audible, but you do not know what you are missing until you put the supplied cable back in a direct comparison.

Conclusion

The final question is whether it is worth the expense. For me, the answer is ‘yes’. The experience of the music improves and that is the criterion. Nevertheless, replacing the dc cable is the very last thing I would consider replacing, though. Think of it as a gift to yourself in this, sometimes absurd, hobby.