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Why does USB feature so much in discussions about DACs when the newer HDMI seems better?

I am a bit confused about the frequent mention of USB in the context of stand-alone Digital to Analog Converters (DAC).  Why is HDMI left out?  Is this a US versus Europe / Asia thing?

The Universal Serial Bus (USB) was introduced in 1996 by a group of computer manufacturers primarily to support plug-and-play for peripherals like keyboards and printers.  It has only two signal wires, plus two wires that can supply DC power.

The High-Definition Multimedia Interface (HDMI) was specifically designed by a group of television manufacturers for transmitting digital audio and video in many formats.  It hit the shops around 2004.  There are 19 pins supporting four shielded twisted pairs, and seven other wires (3 of which can instead form a shielded twisted pair for Ethernet).

I have three universal disk players from Sony, Panasonic and Reavon, which all have two HDMI outputs, one can be dedicated to audio only, the other carries video or video plus audio.  (Only the Panasonic does not support SACD).  My Marantz AV 8802 pre-processor has 11 HDMI connections and only two USBs.

Of course, both USB and HDMI continue to evolve.  Then there is the Media-Oriented System Transport (MOST) bus designed by the automotive industry, which looks even better.

Why is it so?

128x128richardbrand
richardbrand's avatar
richardbrand OP
189 posts
 

@emergingsoul

All of my recently purchased silver disk spinners support two HDMI connections, from the very cheap Sony transport (A$250 or so) and up, I guess for exactly this reason. In my case, the lauded Texas Instruments Burr Brown DACs in my Reavon player turned out to be far worse than the eight 2-channel AKM DACs in my AV pre-processor.

I would encourage you to read the specification sheets of any DAC chipset you are considering. For me, it is very important that they natively support Direct Stream Digital (DSD) which I guess rules out R2R. If the specification sheet does not mention DSD, you can bet your top dollar the DAC does not support DSD.

I note in passing that DSD can be mathematically converted to multi-bit without interpolation, but multi-bit needs interpolation (guesses) to go the other way.

larsman's avatar
larsman
1,982 posts
 

@richardbrand - can't say for sure, but I'd guess that most people who stream do it from their phones.... 

mapman's avatar
mapman
22,311 posts
 

@emergingsoul maybe this. I have one I’ve used just for digital audio output and worked well.

 

https://a.co/d/fGmgPpQ

skeptikal's avatar
skeptikal
33 posts
 

@rbstehno 

How do you figure?  USB is almost always bit-perfect.  When it's not, due to something being horribly wrong, you would definitely hear clicks and pops.  High end USB cables are snake oil, and there is nothing wrong with USB in general.

rbstehno
1,458 posts
 

I don’t reply to cable naysayers, if you can’t hear a difference between cables, no sense talking anything audio to you.

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