Crackly sound

[F. B. I. Guy]

Hi all,
I'm getting very annoying crackly sound from Quake. I tried both ProQuake 4.52 and DirectQ 1.9.0, both have this problem.

Here's a screenshot of the ProQuake start up console:

I suspect it may have to do with that ridiculously low sample rate, but have no idea why it's that low.

Thank You

[Baker]

My gut instinct:

You have too many tasks running or something eating CPU. Have you tried restart your computer? Anytime I've had that problem in the past, I had something in the background (another game) or was low on memory (press CTRL-ALT-DEL to bring up task manager and then click the processes tab ...)

But first, eliminate your sampling rate thought by trying this:

Start DirectQuake with -sndspeed 44100

Like "c:\Quake\DirectQ.exe" -sndspeed 44100 in the Start->Run box or however is easiest for you to do this.

[F. B. I. Guy]

Oh wow, thanks for that very fast reply! That definitely fixed it in DirectQ, but the switch didn't seem to change the sample rate in ProQuake. Is there an equivalent option?

[Baker]

Oh wow, thanks for that very fast reply! That definitely fixed it in DirectQ, but the switch didn't seem to change the sample rate in ProQuake. Is there an equivalent option?

I'm pretty sure there isn't an equivalent option in ProQuake [unless there is some super obscure GLQuake setting inherited.].

DirectQ pretty much does everything ProQuake does, so you should be set.

[F. B. I. Guy]

I'm alright with just using DirectQ, and I thank you for helping me with this, but do you have any idea what would cause the sample rate to be so low in ProQuake? I would prefer to use ProQuake as it is cross-platform (although I do mostly use Windows anyway) and I have the option to use OpenGL. I like to use open source software when it is an equal or better alternative to proprietary software (DirectX/Direct3D is closed source, right?). However, if you don't know, it is not a big deal at all.

Thank You

[Baker]

but do you have any idea what would cause the sample rate to be so low in ProQuake?

It is the Quake default. So that is what ProQuake uses.

I like to use open source software when it is an equal or better alternative to proprietary software (DirectX/Direct3D is closed source, right?

The DirectQ engine is open source. Although DirectX/Direct3D is Windows-only, is that any more proprietary than a closed source NVIDIA driver on, say, Linux?

DirectQ is just as open source as ProQuake.

[In fact, there are a number of similarities between DirectQ and ProQuake ... like the ProQuake Direct3D renderer version (dxpro452.exe) ... mp3 support on Windows ... the list goes on ...]

I'm a multi-platform guy myself who prefers open source when all things are equal. MH, the author of DirectQ, is as open source as you can get ... mhquake: Going Public

[F. B. I. Guy]

Oh, so does that mean the cracklyness I'm hearing is "normal" then? And I did know that DirectQ was open source, it was just the OpenGL vs. DirectX/Direct3D that I meant originally. It's not that I have a problem with closed source software though, I don't. Like your example, I do use the proprietary nvidia drivers when I use Linux just because the open source drivers can't perform nearly as well in 3d. Thanks for your quick help on this matter, and sorry if this has been asked before, I searched first and didn't find anything.

[Spike]

you can try increasing the _snd_mixahead cvar (yes, leading underscore).
it will increase latency but should reduce/stop crackling. too high a value will not work very well though (we're talking seconds here).

the default sample rate is 11025, which is generally very low by modern standards. many devices only actually support 48khz nowadays (rather than 44khz), and upsampling generally requires the driver has access to the audio in advance.
too low a mixahead value will mean your driver reads old data within each audio frame (more likely if you have another process stealing cpu), which can result in constant or periodic crackles.

quake's audio is all a very timing-dependant feature.

[F. B. I. Guy]

I tried setting _snd_mixahead very high and it is still crackling, I have a Realtek ALC888 which I have tested before to find it does not resample. Thank you for the suggestion, though. Since changing the sample rate in DirectQ fixed it, we have to assume it's just the sound sounding bad right? But I'm curious as to how DirectQ is able to change it; If DirectQ is able to change the sample rate to 44,100hz, and it makes a difference, doesn't that mean Quake's sounds are at least higher than 11,025hz? Or does DirectQ have its own sounds at different sample rates?

[Mindf!3ldzX]

have you tried changing the frequency from the Operating System side? It has helped me in the past, because the frequency that is being output + the frequency the game is using don't mix well.

[F. B. I. Guy]

No, since my card does not resample, it just outputs what it is given, and I do not have to set a sample rate. Thanks for looking here and trying to help . Could this cracklyness be aliasing from sound higher than 5512.5hz due to the Nyquist-Shannon sampling theorem? Has anyone listened closely to the default sounds? It's not a random crackling that would be caused by a buffer issue (like Spike kindly suggested), but it actually just sounds like almost every sound has a crackle to it, and to me it seems to correlate with higher frequencies, pointing to the theory I mentioned earlier in this post.

Thanks for all your time and effort!

[Mindf!3ldzX]

No, since my card does not resample, it just outputs what it is given, and I do not have to set a sample rate. Thanks for looking here and trying to help . Could this cracklyness be aliasing from sound higher than 5512.5hz due to the Nyquist-Shannon sampling theorem? Has anyone listened closely to the default sounds? It's not a random crackling that would be caused by a buffer issue (like Spike kindly suggested), but it actually just sounds like almost every sound has a crackle to it, and to me it seems to correlate with higher frequencies, pointing to the theory I mentioned earlier in this post.

Thanks for all your time and effort!

the program Audacity could re-sample the audio files possibly, to the frequency your needing to avoid the resample issue.

PakXplorer is what I use to dig inside Pak files. Rip out the audio files using a pak browsing like PakXplorer, change audio files sample rates, then stick them back in.

This is another avenue for 'forcing' a desired effect, because if you resample the actual audio files there is a chance Quake will be forced to acknowledge this change? Maybe it will break Quake? IDK! Its a thought though...

[F. B. I. Guy]

Alright, I extracted grenade.wav from pak0.pak, and it is indeed 11,025hz, so I'll assume all the sounds are at that rate. This must mean that DirectQ and other clients which provide a sample rate option just resample and possibly interpolate what is missing. I'm not sure how well this works, and upon learning that the files themselves are natively at 11,025hz, I'd rather use that rate. Another thing, I'm beginning to think this is a hardware thing because I played the file rapidly and the crackling sounded different each time. I then resampled it to 44,100hz and the crackling was gone. The important part is that the crackling sounded different each time I played the file because this means the crackling is not actually part of the file. I'm going to ask the people over at HydrogenAudio if they know of any hardware or software things which would cause this, as it is now definite that it isn't a problem with Quake. I will of course continue checking here for anything new if anyone has something to say .

Link to HydrogenAudio thread if anyone's interested

Thanks for that tip, Mindf!3ldzX

[Baker]

Me thinks you are chasing ghosts.

I could easily add -sndspeed parameter to ProQuake in any given 3 minutes of spare time.

But at this time, if I were to do an update to ProQuake Windows there would probably be 50 things I wanted to do it at the same time.

The code goes like this ... it is simple ...

	do
	{
		int sound_hz = 11025;  // Default
		
		do
		{
			int argnum = COM_CheckParm("-sndspeed");
			int sound_requested_hz;

			if (!argnum)
				break; // Command line param not found

			if (argnum + 1 >= com_argc)
				break; // Isn't a next argument

			sound_requested_hz = Q_atoi (com_argv[ argnum + 1]);
	
			if (sound_requested_hz != 44100 && sound_requested_hz != 22050 && sound_requested_hz != 11025)
				break; // Isn't one of the three accepted values		
	
			sound_hz = sound_requested_hz;
	
		} while (0);

		shm->speed = sound_hz;

	} while (0);

[F. B. I. Guy]

Well yes, but that has been determined to not be the problem. I figured that the problem is with my setup whether it be hardware or software, but it isn't Quake. The -sndspeed option would be a sort of fix, but it isn't ideal because the files themselves are at 11,025hz, and resampling them technically should not make a difference unless there is some sort of interpolation, in which case I would still prefer to use the original sounds as they were released. I want to find out what is causing this in my specific setup because it might be affecting other things without me having known before.

Thanks for the help you've given me thus far!