All inputs are pattern matched and buffered.
2 Likes
I’m always humble about what my ears hear, in the sense that I could be proven wrong. It’s surprising, though, that I heard such differences between USB cables. These were not subtle. The biggest difference is in the bass. With one USB cable I tried, the midbass was recessed and the low bass was lacking pitch definition. Through the coax input (with a Gustard U18 DDC and a very good coax cable I have) there’s prodigious bass. The difference is so startling that I can’t see how I’m imagining it. I can tell whether a low bass note is audible over the midrange instruments, or whether it has a clear pitch… at least I thought that was pretty obvious.
With several USB cables, there was very good resolution and a gorgeous, high-resolution midrange (but poor bass). With another USB cable there was less resolution, and with the coax input there’s a higher noise floor and a loss of refinement.
I suppose they weren’t as big as changing the DAC completely, but they had a big impact on my ability to enjoy the DAC and whether it had synergy with my headphones or speakers. In general the lower resolution options also had less extension, and there was no life in my dark classic LCD-2 headphones (although the sound was much better in a bright headphone). The ones with the gorgeous midrange also had the bass recession, so I couldn’t enjoy rock music or jazz as much.
I’ll be able to test the I2S input next week, and I want to let the U18 burn in for a while. Along with the HDMI cable. I’m working against a deadline on the return policy of the U18, so I can’t burn in the cable for hundreds of hours, but I can give it 100 hours or so before I evaluate it.
2 Likes
If the cables you are using are new, the bass may take the longest time to show up from break-in. AQ cables are notorious on break in; even a digital cable takes over 200 hours to reach its peak. I have not tried AQ Diamond before, but my Dragon48 I2S (and Firebird I used to own) and power cords all produce incredible deep bass.
1 Like
One thing that no one has mentioned, is cable length. You want the shortest as possible. Ideally 0.5m. Over 1m is degraded. This is for both usb and I2S each.
My cable lengths are 0.5 to 1 M. Most of them were bought used, but the best USB for the bass is brand new.
I got a hold of a 0.75 meter Transparent HDMI cable (brand new)… letting things warm up, but of course the U18 is very far from completed burn-in, and so is the cable… first listen is promising. It seems to have the best qualities of each of the previously tested USB cables all in one. Good bass (clear in volume level and pitch), refinement of the highs, and beautiful midrange. In fact I’m stunned how refined it is given that the U18 is about the cheapest DDC one can get.
Now for burn-in…
I know it’s best not to make any judgments before burn-in is completed, but my rule of thumb is that it has to least be promising at first and display quite a few excellent qualities. Burn-in improves elegance and refinement but doesn’t change the overall character in my experience.
2 Likes
I’m the same way, Mike. If something doesn’t sound “potential worthy” in my system from the get-go, IME it never will.
1 Like
Until I aquire an Airlens, I would like to try the shorting plug on the unused I2s input of my Mk1. I would like to ask what plug is recommended, I don’t want to use the wrong kind (if even a possibility) and damage anything.
You will have to make your own using replacement HDMI pin out connector. Also wrap in conductive foil also Or buy one from jkrichards or a member here selling theirs.
Don’t forget to short usb input too unless you need it.