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Comment by mangecoeur | Hacker News Reader

The Bluetooth headset latency kills me, especially now so many devices are losing the headphone jack. As a hobbyist musician its unusable, same issue for games.

It’s just worse in every respect and the headsets cost three times as much for the equivalent sound quality.

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I agree for music creation or gaming, but in general wires are definitely annoying and limiting. I could never give up my Bluetooth headphones now for everyday use - wireless plus noise cancellation makes such a big difference when commuting or in the office.

The weird thing is, low latency wireless audio transmission is quite common. Like those used for in-ear monitoring on stage, or wireless guitar cables, that just broadcast over rf frequencies. I don’t understand why no one sells headphones using technologies like this, even if it meant a dongle that needs to be plugged into your computer as well.

Interference would probably be an issue if a full train car of people were trying to use this or something, so I get why Bluetooth is a better, more standardized default. But I would love to have the option of an alternative. I would definitely buy low latency wireless headphones to use while playing music.

// low latency wireless audio transmission is quite common.

The new Qualcomm aptX adaptive standard supports lowish latency - ~80ms.

list of official supported devices: https://www.aptx.com/product-listing?aptx_type=336

It might also work in general , with android 10 devices, but this need verifying.

As a musician I'd call anything ≤10ms low, while 20ms would be okay and usable. Something like 80ms would just be distracting fo anything rhythmic (okay for pad stuff or other slow swelling sounds)

Lhdc ll has 30msec latency.It's included in Android 10.

Maybe this would be ok?

Latency is only an issue if it is not accounted for. I am not sure if this is the case for video on android

Assuming my audio interface is telling me the truth about roundtrip latency, for me anything above 8ms starts to be detectable when playing guitar. Between 8-15ms or so it's subtle and you can kind of trick your brain into ignoring it but it's definitely still there if you pay attention.

And from what I've seen in the best case scenario a usb audio interface is going to have a roundtrip latency of 4-5ms (thunderbolt can be much better, there are some that claim 1 or 1.5 ms).

So IMO that means ideally wireless headphones need to stay < 3-5ms to be an unnoticeable replacement for wired ones.

The GGP says he is a musician--80ms is going to be much too high.

More niche, but close to my heart, it also basically kills rhythm video games. Those can mostly compensate for display latency, but compensating for audio latency is more troublesome--particularly if the exact amount of latency isn't constant.

To follow up, in most rhythm games, the "perfect" timing window is around +/-33ms. In DDR, the "marvelous" timing is around +/-16ms. 80ms is almost a combo breaker.

Top level players can stay in the +/-33ms window for thousands of notes without making a single mistake, and "full marvelous combos" where you stay in the +/-16ms window for an entire song are not unheard of.

That's the kind of timing we are talking about.

...it's interesting to note, though, that because DDR doesn't provide auditory feedback when you hit a note, it should actually be able to compensate for audio latency quite well. The big caveat being, you have to know what the latency is, and that latency must stay consistent, neither of which apply to Bluetooth headphones.

80ms is a roundtrip across the US, that may be low latency for bluetooth, but it's not low latency for the world.

There are wireless headphones using other technologies than Bluetooth. I'm currently using a Steelseries Arctis 7 and it has no perceivable latency (I play rhythm games with it).

And it indeed comes with a USB "dongle"/base-station, with a cable and about the size of a watch, so not really usable on a train etc. (I use wired headphones when working away from my desk).

The best part is that the headset can be connected with a wire to both Xbox and PS4 controllers.

Also the custom dongle has an 3.5mm output plug for speakers, which will automatically turn off when you switch on your headset.

If only Steelseries would make noise-cancelling headphones...

I think the first gen AirPod was 200ms, and current AirPod Pro had it down to ~150ms. Which is already the outliner in the industry as most are still 250ms+.

Compared to Wired Headphone of 5ms latency.

At least Apple continues the R&D to lower latency. Hopefully someday it will reach sub 50ms.

Does the phone adjust for this when playing videos? Because I find even 50ms desync between audio and video to be very jarring.

That is a very good point. I have no idea as I dont use it to watch video. Would not be surprised to see if that was the case.

Yes, phones delay video playback so it matches the reported latency of the audio device. This works via networked audio protocols as well, at least on Apple devices in my experience.

The popular type is from Qualcomm called AptX Low Latency (not the same as 'lossless' AptX HD versions) and you need it on both sides xmt/receive. I have never seen this supported natively before so I got them as a pair of headphone jack to BT dongle adapters. Video works fine on Hotel TVs which was my normal useage.

A normal old school ISM band headphone with transmitter base is better for TV but the dongles travel better.

This can be easily seen in action when playing audio over AirPlay where the latency is ~2 seconds. When you press Play the video waits for a moment to compensate for the audio delay and only starts after the two-second delay to sync with audio.

1 frame at 30fps lasts 33.33 ms. I work as a freelance rerecording mixer and can assure you that a shift of one frame can definitly be noticible.

However there are some people who are more sensitive to this than others.

50ms would be two frames at 25fps, which is already quite much indeed. Anything beyond that is just a crime against anybody who worked hard to sync sound and image.

No need to wait for apple. Low latency was a thing many years ago... Where we are talking about ~40ms over bluetooth.

What devices support that/

Not sure what the best way to look for it is, but searching for devices that support aptx low latency might be a decent indication.

https://www.aptx.com/product-listing?product_category=7&aptx...

40ms is not low latency. It's good for Bluetooth, but it's not low. Low latency, as usable for rhythm games or music, is more like 10ms.

My TV already has higher latency than that and I manage on Rock Band just fine - anything that depends on A/V synchronization is generally aware of latency being a problem and has knobs for the users to adjust for it.

That being said, waiting multiple frames for video playback to start while audio buffers fill and transmit is a shitty experience - so it’s always good to reduce it.

I don't think wired headphones really have latency of their own. A single audio sample takes less than a microsecond. The latency will all come from upstream buffering, which will depend on the application and the OS.

Yup, not sure where the OP got the 5mSec number; perhaps it's about the soundcard buffering but then it's probably sort of high end using ASIO drivers and a rather small buffersize (say 192 samples at 44.1kHz) because I duoubt your everyday buit-in soundcard achieves that. But it cannot be about the speed of the analog signal from the DAC until it reaches your speaker: too lazy too look it up but worst case IIRC is still half the speed of light so not even near mSec range.

5 milliseconds is about what you'll measure for latency if you measure a wired headset, but yes, you're really measuring your sound card.

c ≈ 1ns/ft

Tyvm, this is super handy! More precisely, ~1.01670 ns/ft (~0.983571 ft/ns).

1ns = 300mm (or 30cm)

1us = 300m

1ms = 300km

Just to be pedant, c is the speed of a photon in a vacuum. Electrons are much heavier and are traveling in a medium, copper.

[0] https://en.wikipedia.org/wiki/Drift_velocity

The signal speed has nothing to do with the electrons’ drift velocity. It is a bit slower than c, but negligibly so.

I completely agree with you .. The latency in wireless headphones is bad .. It is clearly noticeable in games and even in general music playing sometimes .. I cant imagine people playing serious games on mobile devices without headphone jack.

I simply can't imagine people playing serious games on mobile devices period.

i feel ya.

people with a desktop computer are a minority thou.

I simply can't imagine serious games.

I got tired of having ads constantly shoved in my face for games I already paid for that then go free. That's when I realised games on mobile were never going to work for me.

Handheld consoles have lots of serious games. You just need to be on a platform that values serious gaming, not 5 min play sessions.

The only advantage is that when I'm running there isn't an annoying cable to fuck with. There is no other benefit that I can see. But I started running more to justify the purchase. Ahahaa.

Same here, but now when I run past other people using wireless devices the sound breaks up. Still probably better than a cable swinging around.

Same. I only got bluetooth earbuds for going to the gym. I specifically got ones that are sweat and water proof because otherwise I wouldn't use them. Cabled earbuds are far superior in every other way.

I’m waiting for some airpods to be delivered today so this is painful to read. I don’t mind a few ms of latency but are we talking noticeably bad latency? The only experience I have is with BT pairing with my car for music. I don’t even use voice in the car.

For playing music or even calls you won’t notice any difference.

The problem is trying to use and app like GarageBand where you need instant response to instrument control. In fact, first time you open GarageBand and it detects you’re using Bluetooth it’ll give you that warning.

Thanks. Just arrived and saw that. It’s not that bad though. I’m not using them for GarageBand though. Phew :)

> For playing music

What do you mean by "playing"? I play the digital piano with wired headphones, and with bluetooth sound it is absolutely unplayable due to the latency.

Playing as in pressing play and listening. He was separately talking about interactive playing with the GarageBand example.

In my experience it varies a lot. I don't have airpods but I have some other wireless earbuds without any noticeable latency. Later I bought a different model from the same manufacturer (Anker) and they are useless for video of any kind. I also have a pair of Sony wireless headphones that have no latency I can discern.

Watching videos and listening to music is fine, devices usually delay video playback to match the latency so you don't notice any difference. The latency problem really only matters for when you need instant feedback for your actions: playing games, editing audio etc. Even then you get used to it.

I only notice it on my AirPods when I pause what I’m listening to. I have “double tap right pod” as toggle play/pause. “Tap tap” and wait, often I’ll “tap tap” again just as it pauses only then to have caused it to play again. I have to trust that my initial tap tap registered.

I’m definitely 9/10 for wires rather than against.

But on the minus side, I have a chirp in my headset (obviously some interference from the motherboard) when connecting with a wire that isn’t there over Bluetooth.

Sometimes wires fail too.

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