24 or 32 bit audio capture within WinUAE

[EAUniW]

Is it possible to record audio within WinUAE at 24 or 32 bit resolution? I record unfiltered, non-interpolated audio in 4 channel mode at 192khz but the resolution is limited to 16 bits and I'd like to ensure the resolution remains as high as possible until I've finished mixing and render down to 44.1khz / 16 bit audio at the end.

[Toni Wilen]

There isn't really need for higher bit depths because Paula is 100% digital (even volume control is digital PWM). It is also fully linear (minus small errors in DAC in real world).

8-bit sample + 6 bit volume (actually range is 0-64, 63 is not full but 64 is full volume so it rounds up to 7 bits) = 15 bits, which is enough without losing any quality.

[EAUniW]

I know there isn't a big reason for going beyond 16 bit resolution in that circumstance but it'd be good to have especially when recording at 192 khz to ensure complete accuracy across every part of the recording and mixing stage.

Then again, once I'm mixing and using EQ etc I'm hardly representing the unfurnished original audio.

[ceztko]

Originally Posted by EAUniW

I know there isn't a big reason for going beyond 16 bit resolution in that circumstance but it'd be good to have especially when recording at 192 khz to ensure complete accuracy across every part of the recording and mixing stage.

Then again, once I'm mixing and using EQ etc I'm hardly representing the unfurnished original audio.

I think what Toni want to say is that you there's no potential quality gain if WinUAE would record naively at higher bit depth or sample rate. At 16 bit you already have the most pristine rendition that Amiga can give you. If you need to mix you just resample, as you are probably already doing.

[BastyCDGS]

Hi Toni!

Originally Posted by Toni Wilen

There isn't really need for higher bit depths because Paula is 100% digital (even volume control is digital PWM). It is also fully linear (minus small errors in DAC in real world).

8-bit sample + 6 bit volume (actually range is 0-64, 63 is not full but 64 is full volume so it rounds up to 7 bits) = 15 bits, which is enough without losing any quality.

Remember that Paula supports sample rates up to 56kHz and that the OP might record from Toccata output? So at least having a higher sample rate would be nice.

If recording audio from Toccata output is possible, 24-bit might be useful as well, since Toccata supports 16-bit samples (not sure about volume bit depth, but I guess it's 6 or 8 bits).

Anyway, the best solution probably would be to use Windows codec system (if WinUAE doesn't already do that).

A solution for the OP that would work now is to install a virtual soundcard driver which records to harddrive. Would this work if the virtual soundcard driver is set to 24bit and 192kHz. Would WinUAE render it to that solution?

[Toni Wilen]

Originally Posted by ceztko

I think what Toni want to say is that you there's no potential quality gain if WinUAE would record naively at higher bit depth or sample rate. At 16 bit you already have the most pristine rendition that Amiga can give you. If you need to mix you just resample, as you are probably already doing.

Exactly. Sample editors will use 32-bits internally anyway.

Originally Posted by BastyCDGS

So at least having a higher sample rate would be nice.

Just type higher sample rate in the dialog box!

If recording audio from Toccata output is possible, 24-bit might be useful as well, since Toccata supports 16-bit samples (not sure about volume bit depth, but I guess it's 6 or 8 bits).

It is not same thing as Paula volume. Volume in sound cards is user setting (like volume knob in stereos), no program that plays via sound card adjust volume in real time. Recording stores audio before volume control.

[BastyCDGS]

Originally Posted by Toni Wilen

Just type higher sample rate in the dialog box!

Ah ok, didn't test that. Nice to know! Thank you!

It is not same thing as Paula volume. Volume in sound cards is user setting (like volume knob in stereos), no program that plays via sound card adjust volume in real time. Recording stores audio before volume control.

Ok, didn't know that recording happens before volume control.
Then using more than 16 bit really doesn't make any sense.
Unless Paula would have more than 4 channels. However, there is a special case which should be consiered:
If interpolation is used (don't know, if recording honors interpolation settings) the output technically takes advantage of 24 bit and 32 bit resolutions.
However, I doubt that someone would be able to hear the difference.

[Thorham]

Unless Toni adds Paula's DAC's non-linear characteristics to WinUAE (and even then it's doubtful), there's no point in more than 16bits because there's no data to put in the extra bits. If you need extra bits for editing, just add them with your audio software.