I don’t see rationale to use anything longer than one-meter, (outside of convenience) if performance is a primary criteria in the system design… I personally consider one-meter, the maximum length for a wire-design USB digital-audio transmission cable… 
The sweet spot for performance of a well designed USB cable seems to be 1.5 meters.
This is also the lenght I would consider to be perfect for convenience.
The WW USB-C cable is only USB 3.1 specs so according to @Jud it should be possible to offer lenghts above one meter.
@matt
Since I use two DACs, I’m using two 1.5m AudioQuest Cinnamon USB cables.
USB 2.0.
They work perfectly.
I think this size is ideal.
I read once, I don’t know if it’s true, that short USB cables measuring 0.5m or 0.75m are more subject to interference.
Agree,
I found this post from 2021 with USB cable length comparisons:
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It is well known that a longer cable acts like a filter… We want to manage the EMI emissions from the USB cable and EMF, VHF and UHF interference migrating into the cable, [ 30 - 300 MHz (VHF) {wavelength = 10–1 m} ], [ 300 MHz - 3G Hz (UHF) {wavelength = 1 m–100 mm} ]… A well designed USB cable will reject RF interference in concert with a good earthing/grounding scheme.
The longer the cable the higher the latency… What works for one system may not be so good for another as there are many synergies to consider that influence the digital-audio code integrity.
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Another viewpoint to consider…
This test Amirm did doesn’t make any sense.
He took the worst DAC that existed at the time, to come to the conclusion that shorter cables were better.
In the final conclusions he corrected this.
Summary
For the first time anywhere, we have shown that we can change the analog output of a DAC by changing how we feed it in digital domain in USB. Shorter cables provided improvements that were visible. Alas, two other factors conspire to make this non-news:
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Schiit Modi 2 that I have tested is horribly designed. It is sensitive to both USB power and data noise. Even a cheaper DAC like Behringer shows that such sensitivity is due to poor DAC design than anything to do with USB cables. The Behringer performance is better than Schiit with any cable and shows no need for tweaking the USB cable.
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I have hugely magnified these differences. Without this magnification, the differences even with lousy DACs like Schiit are literally in the noise.
So nothing here explains the fantastical subjective differences people report between USB cables. I suggest those people conduct some blind test to get to the truth of whether they are hearing any differences especially if they are using better DACs than Schiit Modi 2.
It appears that given the USB transceiver implementation of the Schiit DAC, the measurements show a difference, and this is clearly explained in the comparison to the Behringer DAC, where no appreciable differences were observed, apparently due to better USB transceiver implementation in its design topology… But there was an observable difference with a shorter cable on the Schiit DAC… This was not an anomaly, however audible this may or not be, under subjective evaluation.
My take-away from this was that any well designed USB 2.0 cable of reasonable length, will get the signals to the DAC with relative integrity to the entire signal path. He does not compare USB 3.0 to USB 2.0 cables in this investigation and he defers to a subjective listening evaluation.
In this context it should be mentioned that Schiit Audio have since 2020 their own USB solution named Unison™ which is not based on XMOS or Amanero. This solution is engineered very well and sounds very good according to people around the world who listened to.
The Modi which was measured by ASR is the cheapest Schiit DAC and I don’t know if it was equipped with Schiit’s Unison™ solution at the time of reviewing.
I would recommend to take the comments of ASR with a grain of salt.
https://www.schiit.com/news/news/usb-elevated-introducing-unison-usb
Only if you are considering purchasing the updated version of the Modi DAC with the new Unison™ USB topology based on this investigation… Otherwise this particular investigation is valid, as a comparative DAC was juxtaposed, in-order to provide more insights…
As is always the case… take all subjective impressions and quasi-objective observations by third-party pundits, with some level of skepticism… It’s all part of the learning process and the qualification process in determining the value of the information provided… From this point I recommend digging deeper into the technology and the processes of evaluation.
What we do see in the ASR evaluation is a difference in response of the DAC under test, corollary to the length of the USB cable… In the graphical display below, which is showing differences at -130 dB to -140 dB, we see the UpTone USB 2.0 adapter performing better… The question is whether or not this difference translates into a tangibly perceptible, and qualitative improvement in output sound-quality.
(This is the comparison of the ‘worst long USB 2.0 cable’ (YELLOW) and the UpTone Audio USB 2.0 adapter at full-scale) (RED)
Because the results of scientific experiments show our memory for sound characteristics (except loudness) without a lot of training lasts about 4 seconds, I don’t think the usual sorts of blind tests would do much good. Diana Deutsch - Short Term Memory for Tones>
I’m not arguing sighted tests are any better, and in fact of course they can be worse. I’m just saying that the sorts of informal comparisons you can do at home, blinded or not, should probably not be used to come to any hard objective conclusions about whether differences can or do exist. But as far as I’m concerned, that just means you can’t tell anyone else what to like. Be happy with whatever you enjoy.
I put this summary of Amirm’s test, because I thought he should have gotten a good DAC to do the test and measure if there was any difference.
Our auditory memory is actually very short. Some say that by the time you change a CD, you’ve lost track of what you heard.
Basically the 4 seconds you wrote.
I already had and still have some USB cables. In my opinion there may be differences, but they are subtle.
But of course, when you look at a well-built cable, it visually gives the impression that it could be helping to improve quality.
And of course, the best thing is for the person to feel happy with what they like.
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The Diana Deutsch experiment is based on discrete tones and relationship to other discrete tones… 
Music is a complex synergy of timbre, pitch and dynamics… If you can’t remember the sound of the melody of “Mary had a Little Lamb” or some other little ditty, playing on your system, then of course you will have problems retaining more complex interplay of all musical and contextual sonic elements as they are perceived through your playback system…
This is patently not true…
Musicians can hear the music in there minds-eye and transmogrify these complex interplays of timbre, pitch and dynamics into musical reality through their instruments, voice, and in the creation of complex compositions… If you ever watch a great instrumentalist performing without sheet music to guide them, you will realize this person is recalling every nuance of the performance, from memory. (I know because I am a musician that does not read music)
What we perceive is individual in nature, yet relative to the common reality we all share…
You are confusing what auditory memory is.
It’s one thing to remember how to play a song, its arrangements, etc.
Another thing is how this song played to compare, this time is in the order of seconds. What you keep is the feeling of whether you liked it or not.
Unlike you, I studied music in a conservatory for many years as a child, reading sheet music, but today I no longer remember it.
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Familiarity is reinforced by repetition, and familiarization of tonal memory and nuance is reinforced by the repetitive experience of listening to the sound of our systems… Just as any musician is familiarized with the nuances of timbre, etc, produced by their instrument… For instance, I can discern the nuanced tonal spectral differences between a Bösendorfer and a Steinway in a recording, or a concert grand from an upright grand, without seeing the instrument, no matter the pianist, from the memory of recorded performances I have repetitive familiarity with, when I hear these instruments in a recording that I have never listened to previously.
That’s pattern matching, at which humans excel. But it takes quite a lot of repetition. Experiments have been done that suggest a week of full days of training is insufficient for some types of musical pattern matching.
And the differences we’re trying to get at are often subtle, nothing so apparent as just remembering the correct pitch, as in the Deutsch experiment I linked.
One interesting corollary of what you mentioned is that what we hear repeatedly is what sounds right to us. It becomes the pattern we match against. This may correspond to objective accuracy in some respects, perhaps not in others.
It is a reference from which to juxtapose against…
The cognitive bias of “what sounds right to us” is a product of familiarization… This bias is revealed in double-blind comparisons… Floyd Toole and Sean Olive demonstrated this in their studies on subject-based cognitive bias, and this bias can be mitigated in the subjective assessment during simple blind juxtapositions.
In the context of our playback systems, we have a familiarization bias that we use in the comparative juxtapositions of the changes we make in the configuration at any level of the experience, that is highly refined in one that is an active and critical listener… It is difficult to make moot the the cognitive biases that may influence that interpretation, however. This requires a more disciplined dogma of constant self re-evaluation.
Our biases filter our perspectives about our auditory perceptions and can enhance or diminish our ability to engage with the reality as presented by our systems, and the reality presented by any changes we make to our systems, of which we are sensitized.
I like to use this simple demonstration to reveal how sensitive we are to auditory perceptual change… It goes like this.… Close your eyes and walk into a closet (empty or filled) stay there for a minute, keeping your eyes closed… Keep your eyes closed and exit the closet, with your eyes closed… You will immediately discern the transition from one space to the other.
I don’t believe that with DACs of similar quality, even from a different brand, in a blind test anyone could know which one is working.
Even with music that we are used to listening to frequently.
Maybe those who only use headphones have an advantage. I use headphones occasionally, I’m sure I wouldn’t notice.
A while ago I received a video, where people listening to music had to try to figure out what type of device it was.
Everyone praised the quality and mentioned several expensive brands and models.
When the equipment was shown, it was very simple and old audio equipment.
It was fun to see people’s faces. 
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