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Ask HN: Why isn't an open source A/V receiver a thing?

15 points by cromka ↗ HN
So FFmpeg can decode pretty much any modern home theatre audio standard, including the multi-channel Atmos and DTS. It can take HDMI input, process the audio as separate channels on the fly, mapping them to a sound card, while passing through the video further out. There are very good sound cards that can process the channels and pass the analog signal to also very good and inexpensive, audiofile-level amplifiers.

Why isn’t building a modular A/V receiver a thing, then? Not only it would allow to stay up to date with all the current audio standards, it would allow to update the sound cards and amplifiers independently as the needs change.

Meanwhile we’re pretty much forced to upgrade our receivers every couple years because they don’t update them to support new standards — like the Dolby Vision, which a receiver merely needs to pass through to a TV/projector(!).

9 comments

[ 1.8 ms ] story [ 46.3 ms ] thread
jiveturkey
Arent the numerous Android based media players just that?
cromka
They’re just media players, they pass through signal to a receiver for it to decode it into analog sound. I’m asking to replace the receiver itself.
ilkhan4
I've wondered this too, and I even tried to build one a few years back, but I came to the conclusion that most people who care that much about audio don't really care about open source or hacking hardware. They like buying a big, expensive black box that just does the thing and are fine upgrading every few years. Everyone else buys sound bars and there's not much in between.
cromka
I can see that. But as with many other status quos, things change once a relatively viable project appears and gains momentum. The A/V receiver market seems like it’s totally ripe for a disruption. I see no reason why the overpriced hi-fi companies get to own that market entirely. How come the Chinese haven’t taken a stab at it? It’s not like they care about open source licenses, taking ffmpeg, wrapping it up and selling it half the price of high street hi-fi would be befitting.
stormbeard
You can't make an open source HDMI 2.1 driver:

https://arstechnica.com/gadgets/2024/02/hdmi-forum-to-amd-no...

cromka
Well, for now. But 2.1 is bleeding edge and like most stuff it eventually finds its way to Linux or FFmpeg.
selbyk
And by then, what new technology will be out? People dropping money on this stuff often don't want to be constantly 3-5 years behind

Just playing devil's advocate. OSS receiver would be cool

cromka
I don’t think there are many people who drop money on a new receiver every time a new standard comes out. The idea here is that when the time comes to upgrade—say, they update their TV to support Dolby Vision that requires latest HDMI standard—chances are they wouldn’t have to because the standard would already be supported.

Logic and the history of open-source software (OSS) also dictate that as a project gains popularity, more people tend to contribute, so hopefully, new standards would be adopted more quickly.

It's a good question, though!

realityfactchex
Based on a web search, the answer is at [0] by somebodyelse, as follows: "If you want half-way recent codecs or HDMI standards in a diy hardware project the licensing and chipset availability will kill it unfortunately. The same developer has dropped the HDMI from the follow up project because as a DIYer you can't get the chips needed..."

Also, many people presumably do use a PC as a media server. But, I imagine one would still output that to "real" audio and/or video equipment, if one has a listening/viewing setup that warrants it.

Also, I think there are plenty of open source audio amplifier projects. That simpler problem is not exactly applicable to the OP, though, and not subject to the same licensing and chip availability issues as a full blown AV receiver, apparently.

[0] https://www.audiosciencereview.com/forum/index.php?threads/o...