Admittedly, I could be smarter and/or less sleep deprived, then maybe I wouldn’t be having trouble taking in all the technical information. So I’m not saying this is a bad article. But is there a thesis hidden somewhere (even a tl;dr, as the cool kids say)? I made it about half-way through without knowing what the actual problem is before I gave up (see above lack of smarts and sleep). I THINK it’s suboptimal audio quality? (Which, admittedly again, probability says it is, given this is about headphones)
tl;dr: me no brain good but me interested, eli5?
The observation is that most USB-C to 3.5mm (“aux jack”) audio dongles are supporting high quality audio but only support the USB Full Speed (FS) data rate which is not enough for the high quality audio. This causes problems.
Agreed, and this article is written backwards.
Problem: Audio is a low power (relatively low data) signal that goes over wire. Audio data (not audio) sent via USB needs decoding into audio before it gets sent down the headphone wire. Implementation fails due to insufficient bandwidth. Graphs and textual details go into details about the bottlenecks.
I have never owned a phone where the USB port remains functional.
It’s unclear to me what this person is on about. USB type c uses alt mode for audio. The adapters should be simple wires plus a few resistors. There is no adc or dac or amplifier in the dongle…
All two dongles I have used (Google, Apple) have a DAC.
I’m pretty sure the analog ones are the exception, not the rule.
I’m pretty sure the analog ones are the exception, not the rule.
That is correct, and at least part of the reason for that is that most notebooks, and even many smartphones, don’t support them. DACs are so incredibly cheap nowadays that it costs the manufacturer less to put one in the adapter, than to deal with the cost of half their customers returning the adapter because it doesn’t work with their device.
Analog ones require the USB host to support it. USB DACs on the other hand only require the OS to support them since they just use standard USB features. That’s much more compatible.
A lot of phones require DACs, because “internal DACs are noisier”.
