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Comment by recursive | Hacker News Reader

I'm a grumpy old man, and no one can ever make me care about any audio transport fancier than analog stereo. To my dismay, it's getting hard to find TVs that can even provide usable stereo output without some kind of extra decoder box or something. Luckily, last time I bought a TV, I was still (barely) able to find one that had a headphone jack, which I use as a stereo line out.

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Some TVs have a SPDIF output that you can connect to a D/A converter, but that's also an external box which you don't want. The thing here is that modern TVs typically have an integrated Class D amp for their speakers that has a direct I2S input for the DSP. The TV manufacturer doesn't bother adding in a seperate D/A chip on the board as it doesn't need it.

The good thing though is that those cheap $10 HDMI audio extractors work well for this use case if you have a playback device that outputs PCM over HDMI. As a side note those extractors are also a great way of getting 5.1 surround sound from a HTPC running the Dcaenc DTS encoder [1] into an old pre-HDMI AVR.

1. https://gitlab.com/patrakov/dcaenc

This might be off-topic, but I'd like to use this opportunity to complain that basically every modern home theater setup has like hundreds of milliseconds of audio latency.

Is that the same 'every' that have wireless speakers or 'soundbars'?

Because I'm pretty sure mine doesn't. I hate it, I'm the first to point it out or only one bothered by it. I haven't done anything (other than run Audyssey) to stop it, it just hasn't been a problem as far as I can tell.

And I know you're exaggerating, anyone would notice 'hundreds of milliseconds', but still.

I get that audio latency matters for say phone calls (and I can rant about that getting only worse over time), but does it matter for home theater as long as it's known and adjusted for? Maybe it's a bit annoying if you pause and the audio doesn't stop right away, but otherwise, give me a 2 second audio latency and I don't care as long as you've got a/v sync so the sound and the picture line up where I'm sitting.

It makes a fancy HT setup unusable for gaming.

In many cases, that's intentional and required.

Decoding, distributing, processing, and rendering across all the involved components can take in the order of 100's of ms. HDMI 1.3 and up has had a mechanism for equipment to communicate internal delays so audio remains time-aligned with the rendered image.

Some devices will also have manual overrides for this. If you are experiencing significant drift something is likely borked in the setup.

What's it matter if the DAC is inside the TV or out, beyond the one in the TV is probably a cheap piece of crap. The important thing is the TV support plain Jane 2 channel PCM for digital output. From there you can go anywhere and do anything without loss or codec compatibility nightmares.

For me it's because there is no other dac. TV to mixer to monitor speakers via 1/4" TS.

It's still TV to mixer to speakers in that case just the TV<->mixer portion is SPDIF digital instead of TRS analogue. I.e. the mixer is the DAC instead of the TV and the analog portion is limited to the actual connection to the speakers.

TV selection options go through the roof while analog loss and interference in the mixer is eliminated.

Next time I'm in the market, I'll consider this. I'll probably have to get a mixer then too, instead of using this half broken 30 year old one I have kicking around.

fwiw, you can get a higher quality output (if your tv has it) via optical and/or hdmi looking for the "PCM" output setting. on my recent tv (an LG) it was buried in the settings and greyed out until i turned off all the Ai processing bs. only then could my external stereo DAC work.

Is there a DAC that takes HDMI input? That's not big/expensive?

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