When I hesitantly (due to the $500/1.5m price tag) reviewed the SOtM dCBL-CAT7 ethernet cable back in March, I realized the importance of having a high-quality ethernet cable in the chain. Now I have a dCBL-CAT7 running from my modem to my router and two more for my actual source components. I felt the performance justified the price as the sonic improvements were even greater than some high-end interconnects and power cables I’ve tried.

As with all components, the SOtM dCBL-CAT7 isn’t perfect. Aside from its physical unwieldiness, the midrange is slightly recessed and it’s an overall leaner sounding cable. Though possible, it’s atypical for one to tune a system by daisy-chaining multiple interconnects or speaker cables. With an analog signal, this may result in something sonically confusing or veiled.

So what can we do in the digital domain? This is where the SOtM iSO-CAT6 isolator comes in. May Park from SOtM mentioned better sound quality could be obtained by using the iSO-CAT6 isolator in-between two audiophile-grade ethernet cables. The SOtM iSO-CAT6 isolator is a passive and directional device which assists in the taming of EMI/RFI noise that propagates along the cable, even with cables of very short lengths.

The SOtM iSO-CAT6 Special Edition comes with three cables (gray, dark gray, and black) to enable the listener to tune to her liking. The iSO-CAT6 also comes with a generic short cable. I personally would avoid this cable as it sometimes deteriorates the overall sound quality of the cable before it. In other words, if you’re going to use this generic cable, you may as well forego the iSO-CAT6 and stick to a single ethernet cable.

In addition to filtering, the side-benefit of the SOtM iSO-CAT6 grants us the ability to tune our systems in the digital domain. The question is: Does it come at a cost sonically when tuned this way?


In order for the SOtM iSO-CAT6 to shine, you’ll need quality cables on both ends. At a minimum, I would suggest the Supra CAT8 or the SOtM SE black cable. When using the same quality ethernet cables on both ends, the iSO-CAT6 unequivocally provides many SQ improvements:

  • Tightens up and rounds out the sound. Without the iSO-CAT6, instruments and voices sound a bit flatter and less delineated.
  • More vivid, dynamic, and airy. The music just breathes and opens up more freely into space.
  • Enlarges the soundstage a significant amount. Without the iSO-CAT6, the music (surprisingly) sounded more congested and less extended, even with the dCBL-CAT7 cable.
  • Tone and timbre improve and maintain their integrity.
  • Better resolution of micro-details and dynamics, articulation, and overall realism. The stroke of a bow, the pluck of a guitar, and the attack of a kick drum are made more apparent.
  • Imaging, separation, and layering improve substantially.

With quality or identical ethernet cables on both ends, the iSO-CAT6 enhances the qualities of that cable. You’ll get a better sense of grip, definition, and coherence while being bathed in an enormous soundstage. It’s very clean with no artifacts or fuzziness around the edges. You’ll get more of that “the speakers disappear” effect. The only drawback with certain combinations is a leaner sound with a slightly recessed midrange (which could be remedied with other cables/components).

Seasoning Your Sound

At this point, I’ve decided that in order to achieve the highest fidelity, the iSO-CAT6 will have to be an integral part of the audio chain. I thoroughly enjoy the flexibility of tuning with the iSO-CAT6 as you could essentially “blend” the best of two cables. As always, YMMV as the effects of a cable is system dependent. From my experience, even changing out a single power cable could alter the sound completely. However, I feel the relative differences between cables remain true, just perhaps not at the same magnitude. For that reason, I’ve tested these cables across many systems for a more holistic assessment. This included multiple speakers, headphones, routers/modems, the Lumin S1, SOtM sMS-200, and Sonore microRendu.

Quick Tip: The connector on the iSO-CAT6 will easily break the locking tab on the dCBL-CAT7 and perhaps other cables. Just make sure you depress fully before detaching from the iSO-CAT6.

For reference:

  • I prefer a sound with a tilt towards the warmer side of neutral.
  • Timbre is non-negotiable for me. Voices and instruments have to sound natural and palpable.
  • 35-year-old ears with zero listening impairments.