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King Mustard
24th January 2020, 17:25
I have a FLAC music album.

The final track has a hidden song at the end, meaning the track has a few minutes of silence in the middle.

I have selected the parts I don't want in Audacity and deleted it from the timeline.

I've then gone to Edit > Preference > Quality > High-quality conversion and set Dither to None, as I've heard this is the best thing to do in my scenario.

I've gone to File > Export > Export Audio and selected FLAC as Type but there are two options:

Level (0 (fastest) to 8 (best))
Bit depth (16 bit, 24 bit)
Since I don't want to re-encode (as, I believe, FLAC is similar to WAV in that it's lossless?), what should I do next?

I'm happy to use alternate software.

tebasuna51
25th January 2020, 10:59
1) Level: always is lossless. Fast implies big output size, slow (best) -> less output size. Like with modern computers the time difference is inappreciable use best.

2) Bit depth: use the same as the source. If source is 16 bit you waste space with 24 bit, if source is 24 bit you losse quality with 16 bit.
If source is from a CD audio is only 16 bit. You can use MediaInfo or other tool to know the bit depth of the source.

You can use use Audacity to edit the source, if you only do cuts the best option to avoid any conversion is, before load the flac, do:
Edit > Preferences > Quality > Default Sample Format: 16 or 24 like source
The other Quality settings are not used if you only cut.

chros
27th January 2020, 12:43
You can use use Audacity to edit the source, if you only do cuts the best option to avoid any conversion is, before load the flac, do:
Edit > Preferences > Quality > Default Sample Format: 16 or 24 like source
The other Quality settings are not used if you only cut.
Yes. I thought mp3directcut (https://mpesch3.de/) can handle flac as well, but only mp3 and aac is supported (yet?).

StainlessS
27th January 2020, 13:26
If source is from a CD audio is only 16 bit.

I'm pretty sure that I borrowed [EDIT: what purported to be] a 24 bit CD from local libary maybe about 15 years ago, I dont remember what the album was [maybe something like Mike Oldfield Tubular Bells].

EDIT: Maybe it required a special 24 bit player for 24 bit capability, dont remember, or maybe just advertising hype.

EDIT: Seem to have some 24 bit HDCD hits here [played ok in standard CD player]:- https://www.google.com/search?ei=Y9wuXr2eB-Gy8gLc6bbIDQ&q=tubular+bells+%2224+bit+CD%22&oq=tubular+bells+%2224+bit+CD%22&gs_l=psy-ab.3...6012.8450..8765...0.0..0.298.811.0j2j2......0....1..gws-wiz.RYrav-X65hQ&ved=0ahUKEwj9293S6KPnAhVhmVwKHdy0DdkQ4dUDCAo&uact=5

EDIT: HDCD on Wikipedia[High Definition Compatible Digital, D9 gets a mention]:- https://en.wikipedia.org/wiki/High_Definition_Compatible_Digital
a proprietary audio encode-decode process that claims to provide increased dynamic range over that of standard Red Book audio CDs, while retaining backward compatibility with existing compact disc players.

Technical overview

HDCD encodes the equivalent of 20 bits worth of data in a 16-bit digital audio signal by using custom dithering, audio filters, and some reversible amplitude and gain encoding: Peak Extend, which is a reversible soft limiter; and Low Level Range Extend, which is a reversible gain on low-level signals. There is thus a benefit at the expense of a very minor increase in noise.[3]

The claim that the encoding process is compatible with ordinary CD players (without audible distortion) is disputed: not being able to decode the peak soft limiting, a normal CD player will output distorted peaks

In 2000, Pacific Microsonics folded and Microsoft acquired the company and all of its intellectual property.[5][6] Microsoft discontinued the official HDCD website in 2005.

EDIT: The D9 thread mentioned on Wikipedia [HDCD Software Decoder]:- https://forum.doom9.org/showthread.php?t=129136

EDIT: Interesting post in above thread [seems some bits stored in CD sub channel]:
Hi there,

i always wondered why my backup of Kari Bemnes "Norwegian Moods" sounded much worse when burned from wavs i extracted with eac before from my original disc (HDCD, but not labeled as one). I found out why:
while looking through the internet collecting information about hdcd i found an article from a guy called _Ilya_ (http://www.head-fi.org/t/151329/hdcd-technology-in-detales):

"Data range from -30000 : 30000 is linear. Range above and below is non linear. Multiplier coefficients are recorded in sub-channel (part of audio CD format). Sub channel is not big enough to keep additional 4 bits, but it can keep multiplication coefficient.

In other words HDCD data format is a 2 pieswise interpolation to logarithmic scale. Full range is appropriate to 20 bit. Data precision at any point is 16 bit. (technology similar to voice A-law, M-law compression).

HDCD played on standard CD equipment will distort high levels.
HDCD played on separate transport and processor may be distorted because if sub channel is not transmitted, but processor is HDCD capable, processor will try to apply HDCD decoding because it will find HDCD patterns in upper levels, but without sub channel it does not know how to amplify it. The result is floating level (The same may be achieved if you copy HDCD using NERO but do not copy sub channel).
HDCD can not be saved in .wav because sub channel will be lost. HDCD processor will find patterns in peaks, led will flash."

I thought to myself, that would be an explanation why my copies sound so strange, lifeless.

I made a copy with clonecd, activating "read infos from subchannels" and made an image.

Before burning the image, i set the option "don't correct subchannel streams". Burned with Burning Speed 1x, because the subchannels don't have any crc correction, thought it would be safer that way.

And ... got an epiphany after inserting the fresh burned cd in my hdcd-player: I sounded exactly like the original. Finally. Now i know why. Have to rip my other hdcds again as an image with subchannel information.

Without the subchannel - Information it's quite possible you just get quasi 15 bit resolution in your 20 bit file with no dynamic expansion at all.