Flac 24 bit to Stereo/Mono wave file

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HpW
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Joined: Mon Jun 11, 2012 7:48 am

Flac 24 bit to Stereo/Mono wave file

Post by HpW »

Have with V6.51 an issue converting a stereo flac 24 bit 48kHz to a mono wave file.

1. Flac Stereo 24 bit to Stereo 24 bit PCM seams to work without level attenuation

2. Do Flac Stereo 24 bit to Mono 24 bit PCM (selected only channel 1 on GUI) reduces level be 6dB

Is this known or what's the beef about :roll: ??

Hp
Tristan
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Location: Southeast Michigan

Re: Flac 24 bit to Stereo/Mono wave file

Post by Tristan »

Have you had this problem before, with earlier versions of GoldWave, or is the first time you've tried the conversion? I don't really get why anyone would convert a file from a compressed format to an uncompressed one. It seems to me that's inviting trouble all by itself.

At any rate, it's hard to tell what you're doing from your description. Do you mean you select one channel in the FLAC file and convert that to a mono WAV file? Are you using the same sampling rates, before and after? Do you have the same problem converting from stereo FLAC to mono FLAC?

In the meantime, try a 2-stage conversion process: 1) Stereo FLAC to stereo WAV, then 2) stereo WAV to mono WAV. That should work. If you still get a 6dB level reduction after that, you'll know the problems isn't some conversion bug.
Last edited by Tristan on Thu Apr 23, 2020 1:57 pm, edited 1 time in total.
I don't want to read the manual either, but, then, it isn't my problem, is it?
HpW
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Joined: Mon Jun 11, 2012 7:48 am

Re: Flac 24 bit to Stereo/Mono wave file

Post by HpW »

>> Do you have the same problem converting from stereo FLAC to mono FLAC?

YES :lol: so we need some fixes.

Also an issue is converting with higher bit size as 24/32 to 16 bit!
There is no any dithering applied and ends up in artefacts :roll:

Hp
Tristan
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Location: Southeast Michigan

Re: Flac 24 bit to Stereo/Mono wave file

Post by Tristan »

OK, I asked for details, and you haven't given me any. So I still can't tell what you're doing that might lead to conversion issues. For all I know, you could just be pushing buttons at random and praying for the right results.

I convert files from 24-bit to 16-bit in GW all of the time, and I never experience artifacts. I don't know why you're having problems.

I still think you ought to just try my 2-stage conversion suggestion, because that sounds like it would work. You might accidentally discover solutions to some of your other problems in the process.

Update: I see the way to scare you off is to start asking questions. :lol:
Last edited by Tristan on Sat Apr 25, 2020 1:12 pm, edited 1 time in total.
I don't want to read the manual either, but, then, it isn't my problem, is it?
DougDbug
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Re: Flac 24 bit to Stereo/Mono wave file

Post by DougDbug »

2. Do Flac Stereo 24 bit to Mono 24 bit PCM (selected only channel 1 on GUI) reduces level be 6dB
Mixing is done by summation so it's common to reduce both channels by -6dB (50%) before mixing to mono to prevent clipping. If one channel is silent, muted, or excluded, the result will be 6db lower.
Also an issue is converting with higher bit size as 24/32 to 16 bit!
There is no any dithering applied and ends up in artefacts
There is an option to dither 8-bit files: Options -> Plug-in -> File -> GoldWave.

It is considered "correct" to dither whenever downsampling but if you are hearing artifacts, dither, (or the the effects of dither) at 16-bits or better you're not dong a proper-blind ABX test. :P

But if it's important to you, there are lots of other re-sampling applications/tools that will dither.

..Dither is added noise so it's a compromise and some people actually complain about hearing the dither, but you have to do "unnatural" things like cranking-up the volume during very quiet parts to hear it (at 16-bits or better).
GoldWave Inc.
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Re: Flac 24 bit to Stereo/Mono wave file

Post by GoldWave Inc. »

DougDbug is correct. When saving a stereo file as mono, the channels are averaged to ensure there is no clipping [(L+R)/2]. For precise control over how the channels are mixed, I'd recommend using the Channel Mixer effect to mix all the channels into the Left channel, then select only the Left channel (use the "Maxmize" effect, if required) and use "Save Selection As" to save as mono.
DougA
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Re: Flac 24 bit to Stereo/Mono wave file

Post by DougA »

I found this thread because it most closely matches the issue I'm having, and IMO the extra detail in the OP is clouding the real issue, and that's the 6db drop in volume. Well, that's my issue anyway.

I have a stereo .wav file, nothing special, except that when it's recorded there is only a left signal, the right side is 0.
I simply want to "delete" the right track and save the left track in mono mode. But when I do, the two tracks get merged, hence the 6bd drop. (should be easy to reproduce, just make a stereo recording and disconnect one input channel)
I do click the green check box on that channel, and it turns the track black, the icon is a red cross out.
Changing the attributes on the save to 'mono'.
A warning box pops up: "Save with a reduced sampling rate or channels? ... The current attributes have a lower sampling rate or fewer channels than the current file" ... that's good, just what we want .... BUT, go ahead and save it and then respond yes to the "Update sound window with the new format" .. again, good, just what we want .... BUT, while you DO get a mono file, you've lost 6db ... it didn't drop the channel, it merged it !

I believe this is exactly what the OP was all about

The work around's, (copy/paste, etc) if this were just a "one of" would accomplish the issue, but this is a production occurrence and that's not acceptable.
Need I insert, it works on Audacity ? (my current work around) .... but really, that's not an acceptable solution either.

so, bottom line, what am I (we) missing or doing wrong? how does one just "DROP" a channel ... that's all, simple, DROP a channel
Doug
GoldWave Inc.
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Re: Flac 24 bit to Stereo/Mono wave file

Post by GoldWave Inc. »

Simply select the left channel and use File | Save Selection As. That will save the left channel only. Be sure to select "stereo" attributes with the Attributes button if you want a stereo file.

Or you can use Effect | Stereo | Channel Mixer to replace the right channel with the left channel before saving.

Or you can select the left channel, use Edit | Copy, then select the right channel and use Edit | Replace.
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