i2s Cable for Denafrips Iris -> Pontus?

Hi all! Finally got all the pieces to my digital front end puzzle and am getting things hooked up and set up.

What I landed with:

Innuos Zen mk3
Denafrips Iris 12th DDC
Denafrips Pontus II 12th DAC

Right now, I have USB running from the Zen to the Iris DDC, and then using an HDMI cable for i2s out from DDC into the Pontus. I got things setup to where sound is playing, but I have some observations so far.

1. I was using the Zen into a digital input on my integrated. It sounded ok, but wasn't great. I wasn't expecting much, but wanted to have a baseline to see how the Denafrips gear would improve on this.

2. Connecting the Pontus on its own to the Zen, there was an immediate, drastic improvement in pretty much every aspect of the sound.

3. Adding the Iris and getting it configured is where I ran into an interesting issue. No problems getting sound to work by following the walkthrough video, so that was good. However, there seems to be a very slight muffling to the sound overall vs the DAC alone. The sound is less holographic and it took some of the sparkle off. To me, currently, it sounds like a slight downgrade vs the DAC on its own, which shouldn't be the case.

While some of this may be 'fresh out of the box' syndrome that break-in might change a bit, I suspect that possibly using a random HDMI cable for the i2s isn't the best approach and may be contributing to this issue.

Not sure if others that have this combo have run into this at all. If so, would like to hear if the cable choice was the problem or if it was some setting somewhere. The instructions for these aren't the most thorough, so it's definitely possible it's a setting issue as well.

Thanks for any help!



@soix I cannot find any HDMI cables 1 foot or less...DH makes an 20 inch, Wireworld a 24 and AQ a 30...any suggestions ?

@jl35 I use 6” cable from Monoprice for under $7 I mentioned above…


Given my results and at this price I’d highly recommend giving it a shot and see if something else can significantly better it.  Frankly I’m seriously wondering if cable quality or length is more important for an HDMI cable for i2S, and given my experience and what others have said I’m leaning toward the latter.  FWIW.


So quick update: after a few days of pretty heavy listening, it did seem to open up a little more (though some may be attributed to my ears adjusting to the sound). I did still hear a minor difference when the Iris was connected versus just running to the DAC, however.

I received the new cables from DH Labs and...it's a night and day difference. It's not even close. Removed what felt to be a veil over the sound immediately, along with improved the imaging, detail, etc.

While I've heard minor differences with different cables in the past with other components - like slightly blacker backgrounds with nicer power cables, etc - I've never experienced such a drastic improvement just from a couple cable swaps.

Some of it might be switching from a 1m cheap HDMI from amazon to a 0.5m HDMI, since the shorter length is ideal for i2s. Whatever it was, replacing the USB and HDMI cables did the trick and then some.

Congrats!  As I always say — don’t matter how you get there, just that you get there.  Goodonya for not giving up and sticking with it, and now you reap the rewards of your effort.  Would be interesting to hear if you heard more difference improving the USB or HDMI cable if you could ever do that comparison.  Congrats again!

@soix I actually just swapped the HDMI cable back to the old one in the middle of a song, and then back again to see. While the baseline change with just the USB was an improvement, the HDMI cable seems to make the biggest improvement here.

The USB changed alone sounds a bit tighter to me, with moderate improvements in the soundstage, imaging, etc over the old cables, but swapping out the HDMI really made it come alive. Whether it's due to the shorter HDMI cable length or cable quality or a combination of both, who knows, but that seems to be the majority of the improvement.

However, I can't really easily swap the USB back to the old one (it's ziptied up now since I'm a bit obsessive with cable management, so I can't really tell if the HDMI on its own makes the biggest improvement or if it really needs to be in combination.

Either way, now it all comes quite close to the sound from my much pricier vinyl setup. Not 100% there, but I did not expect that at this price point. Would probably need to step up in DAC & Streamer (zenith + terminator II+ maybe) to get much closer, at like 5x the cost. Very pleased!

Of course, it also comes down to the quality of the recordings and files ultimately. Some recordings just don't sound great digitally for one reason or another.