[sdiy] Ray tracing hardware for audio simulation

[Guy McCusker]

Ahh, the AES paper referred to in that article, which may be found
here: http://jd-xlabs.com/AES_Latency.pdf is quite interesting.

For vocals specifically, if monitoring with IEMs, you have essentially
no leeway if this study is to be believed. It seems plausible that
hearing your own voice piped straight into your ears on a short delay
would feel unsettling at the very least.

On Tue, Aug 2, 2022 at 2:24 PM Mike Bryant <mbryant at futurehorizons.com> wrote:
>
> There's hundreds of articles and papers to the AES on this if you Google.  Opinions vary but this is one of the more simplistic ones I refer people to when they complain as it puts the ball back in their court.
>
> https://www.churchproduction.com/education/latency-and-its-affect-on-performers/
>
> As you can see, once you have a wireless microphone and a wireless monitor together with a digital mixer (usually an X32 nowadays - they are just everywhere even though the WING was supposed to replace it)  then you really have no margin left and the singers will already be noticing the effects of the delay.  And there's often nothing you can really do about it of course other than go and buy an old Midas or Soundcraft analogue mixer and a lot of cables for a separate monitor system like in the old days :-)
>
>
> -----Original Message-----
> From: Synth-diy [mailto:synth-diy-bounces at synth-diy.org] On Behalf Of Guy McCusker via Synth-diy
> Sent: 02 August 2022 14:08
> To: synth-diy at synth-diy.org
> Subject: Re: [sdiy] Ray tracing hardware for audio simulation
>
> On Mon, Aug 1, 2022 at 2:41 PM Matthew Skala via Synth-diy <synth-diy at synth-diy.org> wrote:
> >
> > On Mon, 1 Aug 2022, Mike Bryant wrote:
> > > 1mS delay is too much for live voice processing so they need to work
> > > on
> >
> > Move the speaker a foot closer to the listener
>
> I was intrigued by the discussion around the significance of such small latency and started reading about human's ability to perceive such timing differences. Some internet searches led me to the Haas effect, aka precedence effect, as described e.g. here https://en.wikipedia.org/wiki/Precedence_effect
>
> I found it quite interesting to play around with adding a few ms of delay to one channel of an audio track and listening to the effect.
> For me, anything up to 40ms, and a bit more in fact, manifested itself as a shift in the perceived location of some of the sounds. High frequencies in particular seemed to shift left as I made the right channel play later. I did not perceive the two tracks as being offset from one another at all. Beyond 40ms delay the two tracks did begin to separate and sound like a very short echo. If you have not experienced this before it's quite an interesting use of a few minutes! I am starting to think that this is also the reason that manufacturers of hifi speakers recommend placing the speakers a couple of feet away from walls for a "wider soundstage" -- reflections will cause this kind of effect and spread out the perceived location of the sound; presumably at the cost of a weird frequency response thanks to cancellations. If someone here knows more about this stuff I'd be glad for any good references to read up on it.
>
> On the topic of avoiding latency, the above strongly suggests that 1ms here or there is not a problem. But that does not mean you should not try to avoid introducing latency if you can. These systems will be chained together, latencies will add up, and uncontrolled latency can't be a good thing, especially if you don't know which paths have what latency. So it seems smart for engineers to keep it down as much as they can, and it is obvious that manufacturers of low-latency products will trumpet that as a benefit, and others had better catch up.
>
> So I guess I agree with both Mike and Matthew, but Matthew's message made my day, as well as prompting me to look into this, which I have enjoyed. Thanks!
>
> Guy.
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>