Question about possible eARC audio delay

[Jon-Slow]

I've been thinking of getting some speakers for my TV, maybe 5.1, ( movies and games) but I didn't know that apparently I have to buy an AVR. There is so much conflicting information about everything and I'm very confused. 

 

Seems like the audio community that I've asked questions from outside of here are not gamers and so I haven't been able to get conclusive answers. I don't want to pass my video signal through an AVR, the video part of an AVR is useless to me because I'm primarily scared of adding input delay and want my picture to go directly from my PC/PS5 to my TV, and secondly AVRs with proper HDMI 2.1 are so much more expensive.

 

I thought I could get the audio out of my TV through the eARC output and feed it to the AVR. But it seems like that would add delay to the audio. Or maybe not? I'm very confused because I've heard some say it will and some say it wont. I can't be spending lots of money on an AVR and speakers only to findout that games wont have synced audio. I could alternatively, get audio from the optical audio output from my TV and feed it to the AVR, but then I'm told not to do that because the audio would be lossy if I have more than 2 speakers.

 

So it seems like option 1 is to go buy a super expensive AVR with HDMI 2.1 support not knowing if it will add input delay to games, or to use eARC to either feed it to the AVR directly or to add an eARC audio extractor device in between eARC output and AVR( if the AVR doesn't have an eARC port)

 

Is there anyone here using a 5.1 system to play games as well as to watch movies?  

 

( Also I thought maybe I could use the eARC extractor with a used amplifier that would power the speakers and send signal to them, but I'm told that's also not possible. As you can see I'm not an audio person.

[johnt]

25 minutes ago, Jon-Slow said:

Is there anyone here using a 5.1 system to play games as well as to watch movies?

I'm trying to save you from all the audio troubles I've experienced. I would not bother with surround sound for PC gaming. You absolutely need to feed HDMI from your GPU to the AVR for the best sound management. You also need HDMI 2.1, I think, to take advantage of VRR. Audio/video sync issues are abundant with home theater equipment. Sometimes it's as simple as restarting the source media or just living with it.

 

I wouldn't spend my time with surround sound on PC anymore. The intricacies are so frustrating. Optical doesn't support more than 6 channels, however, the game you're playing has to support surround over optical. Most of the time video games and programs just support 2 channel through optical. Second, even with HDMI, gaming in surround sound is not guaranteed or optimal. If the game supports full 8 channels, then consider yourself lucky. Most of the time they do not support a separate LFE or subwoofer channel, and of course the sound is not encoded in a surround platform like Dolby Atmos or Digital, so you are usually leaving it up to your AVR to decide what information gets routed to which speaker. This isn't an issue with movies bc they are decoded. You can usually select a direct mode on your AVR, but if the source doesn't have an LFE channel, then you hear nothing from a subwoofer. Do you need a subwoofer? Nope. But it is a dedicated channel for surround. And then the best part of surround sound is the calibration. It's just not worth it in the long run. It is 100% better in every way when it's working properly. But most of the time it doesn't work the way you think it should. Let me be clear, this is all before you even notice the syncing issues lol

 

I probably spent somewhere north of $20k on audio equipment over the past ten years. I have a simple Audioengine A2+ without a subwoofer at my gaming desk.

[cmndr]

post processing and time matching between speakers usually means you end up with something like +20ms delay. 
If you're not being paid professionally to play games (i.e. you're not making $100+ a month from the activity), deal with an MMR that's like 2 points lower and relax.
Human reaction time is usually around 100ms and the video part will matter more to you. 

As far as modern AVRs are concerned, they support ALLM. You're mostly fine. 

My general set up is videocard -> TV -> EARC to AVR -> speakers
This is a 7.4.4 set up. 


If you're paranoid about latency... go analog to a pair of speakers with a passive crossover and avoid DSP as much as possible. 
This really shouldn't matter. 
Your goal should probably be to have fun, not to get the best score. 

 

Worrying about a relatively modest latency difference is like a runner shaving their legs for aerodynamics and losing to some hairy guy that's just a way better runner. 

[Jon-Slow]

@johnt Hi, thanks for the reply. I already do have a fiber optic HDMI 2.1 going all the way from my PC room to my bedroom and could potentially use that  to even connect directly to the AVR. I could also use an HDMI 2.1 cable to get audio out of my TV into the AVR. So I understand the limitations of optical audio, but my main concern right now is if input delay or audio delay would be a concern with eARC specifically. If even if at the end of the day some games do and some don't support a 5.1 channel, I wouldn't mind switching back to 2.1 for games that don't. But would rather have the system in place.

 

 

@cmndr So do you mean that any 5.1 setup will have delay regardless of if it is eARC or other methods? Because what I've heard about eARC is that it specifically has the delay.

4 hours ago, cmndr said:

If you're paranoid about latency... go analog to a pair of speakers with a passive crossover and avoid DSP as much as possible. 
This really shouldn't matter. 
Your goal should probably be to have fun, not to get the best score. 

 

Worrying about a relatively modest latency difference is like a runner shaving their legs for aerodynamics and losing to some hairy guy that's just a way better runner. 

 

Well I've heard conflicting reports. So I've heard that there could be noticeable latency with eARC, so much so that lipsync would be an issue. After doing long hours of looking into it, I'm no closer to finding a definitive answer. So looking to find people that do this and have experience with it to confirm what audio latancy they get using eARC from TV to AVR

 

I saw a video from HDTVtest on youtube saying the HDMI 2.1 output from AVR to TV doesn' have latancy( which is not exactly what I'm looking for becuase I'm trying to feed audio from TV to AVR), but at the end of it he says something like "this isn't conclusive and he needs better equipment to test".

 

 

 

[cmndr]

14 hours ago, Jon-Slow said:

 

@cmndr So do you mean that any 5.1 setup will have delay regardless of if it is eARC or other methods? Because what I've heard about eARC is that it specifically has the delay.

 

Well I've heard conflicting reports. So I've heard that there could be noticeable latency with eARC, so much so that lipsync would be an issue. After doing long hours of looking into it, I'm no closer to finding a definitive answer. So looking to find people that do this and have experience with it to confirm what audio latancy they get using eARC from TV to AVR

 

I saw a video from HDTVtest on youtube saying the HDMI 2.1 output from AVR to TV doesn' have latancy( which is not exactly what I'm looking for becuase I'm trying to feed audio from TV to AVR), but at the end of it he says something like "this isn't conclusive and he needs better equipment to test".

At most you're losing a frame or two of responsiveness. It's not going to matter unless you're in the top 1% of people in a response sensitive title. RTS, racing, RPGs, etc. won't matter. I don't think arcade style fighting games that require FRAME PERFECT input have many sound signals. The only real "use case" is hearing footsteps in a shooter and even then clear and accurate positioning is going to matter more than getting the sound 1 frame earlier. Headphones can do that pretty well but... then you have to wear headphones. 
 

SOME delay will happen if you need to delay the closer speakers so that the sound from them arrives at the same time as the further speakers. Also subwoofers tend to have a bit of delay into them as well due to their own DSP. 

Data transmission delay is pretty modest, practically negligible. I'm going to guess on the order of nanoseconds (1 millionth of an ms)
It's the time it takes to do digital signal processing (5-20ms usually). 

It's on the order of 20-40ms in totality, including the intentional delay added so that the sound from all the speakers arrives at the same time to the listening position.  It takes a little under 1ms per foot for sound to move, so if you have 1 speaker next to you and 1 that's 10 feet further away it'd end up around 10ms delayed (on top of the time it takes for sound to move). 

I want to emphasize, you shouldn't be worried much about delay unless it's revenue generating. Visual latency is going to matter 10x as much as audio latency and actually HEARING the foot step and telling where it's from will matter more than if it's delayed slightly. 

Don't go on gaming forums (and reddit) for sensible advice, go on them if you want someone to tell you how they doubled the power draw of their system to get 2% more FPS in minecraft and all it cost was enough fan noise that they couldn't concentrate. 

(Also don't go on audio forums... that's how I ended up with 4 subwoofers)

 

Here's an LLM response to sanity check me