FLAC files from 16/44 CD (WAV) files are smaller than MP3s.

[dalethorn]

Note: This is going to be a little complicated, so I will try to cover every factor in this problem I've had.

 

I purchased some DSD (352 khz) files of solo piano music that's fairly dynamic and detailed, with loads of gorgeous harmonics.  I prefer to play my music in 24/88 or 24/96 format, and also be able to convert to 16/44 WAV to play on my 256 gb Apple devices.

 

So I purchased a well-respected converter (Mac version) to make the 24/88 FLAC and WAV files, and carefully followed the instructions given by the music critic who promoted the album, as well as the detailed instructions given by the converter gurus.  Those 24/88 conversions not only wouldn't play on my PC in Foobar2000, they corrupted Foobar so badly that I had to reinstall it.  That process of conversion from DSD to 24/88 and attempts to play on Foobar followed by reinstallation was repeated many times, with input from the persons noted above, with no success.

 

Note that I have over a thousand high-res (24/88 to 24/192) WAV and FLAC files from HDTracks and several other such sites, and I've never had a single problem playing those on my Foobar2000 player.  And I tested a number of those again during this process.

 

So I finally decided to convert the DSDs to 16/44 WAV files, and those played just fine on Foobar2000.  But when I converted those WAV files to FLAC, the FLAC files (Level 5 FLAC) were smaller than MP3s, i.e. about 23 percent of the 16/44 WAV size.  Using that same Foobar2000 and both FLAC converters I have (ca. 2007 and 2014), I've converted several thousand CD/WAV rips to FLAC over the years, and none of those FLACs were less than 60 percent of the WAV file size.

 

I even went a step further to see how my trusty FLAC converter could make files smaller than the corresponding MP3s - I converted a few MP3s (320 kbps, 4 minutes and 10 mb each) to 16/44 WAV tracks (44 mb each), and then I restarted Foobar and converted those WAVs to FLAC.  Those FLACs, which originated from the MP3 files, were now 24 MB each, and Foobar showed a bitrate around 760 kbps when playing.  The "23 percent" FLACs noted above showed a bitrate playing in Foobar of 290 kbps.

 

So my question is, given that I cannot make a FLAC that's 23 percent of a WAV file size from any of the thousands of WAV files that I've ripped or purchased, or even from up-rez'd MP3s, what could possibly be in the WAV files I got from the well-regarded Mac converter that I purchased, that would trick my FLAC converter into making FLACs smaller than MP3s?  The converter software gurus say that the DSD recordings have "extremely low complexity", which makes no sense, and doesn't fit with all of the other experience I've described.

[esldude]

You say your DSD is 352 khz.  Is that DXD?  DSD typically goes 64, 128, 256, and 512.

[mansr]

If you post a sample file exhibiting the phenomenon, someone can probably explain it.

[esldude]

Another thought, Yuri is a member here, and writes software to do this for Mac and Windows.  Maybe even his software you have.  Perhaps he could help.  

 

audiventory

 

Is the user name for Yuri here.  

[dalethorn]

2 hours ago, esldude said:

You say your DSD is 352 khz.  Is that DXD?  DSD typically goes 64, 128, 256, and 512.

 

It's supposed to be "DSD64" I think, but if I'm remembering right, the sample rate is 352.

[mansr]

2 minutes ago, dalethorn said:

It's supposed to be "DSD64" I think, but if I'm remembering right, the sample rate is 352.

The sample rate of DSD64 is 2.8224 MHz, that is 64 * 44.1 kHz.

[esldude]

http://www.sonore.us/dsd2flac.html

 

Here is a free conversion for Mac or Linux.  I have used it myself.  I didn't suggest it before because it only does DSD64 and 128.  Converts to Flac up to 352 khz rates.  Rather simple, but works.  You could try that and see how the results turn out versus what you have done already.   

[dalethorn]

Ignore - bad link.

[dalethorn]

2 minutes ago, esldude said:

http://www.sonore.us/dsd2flac.html

 

Here is a free conversion for Mac or Linux.  I have used it myself.  I didn't suggest it before because it only does DSD64 and 128.  Converts to Flac up to 352 khz rates.  Rather simple, but works.  You could try that and see how the results turn out versus what you have done already.   

 

I will in a bit, thanks!

[esldude]

1 minute ago, dalethorn said:

 

https://www.dropbox.com/sh/st6goiq1q0mjmsz/AACgOP4f6dQLD4m0KLWlb8yJa?dl=0

 

Here's a DSD and the JRiver-made 16/44 WAV.

 

 

I get an error saying the file can't be found on your link. 

[dalethorn]

5 minutes ago, mansr said:

The sample rate of DSD64 is 2.8224 MHz, that is 64 * 44.1 kHz.

 

By my calculation, that would mean the player has to process 11.5 mb per second, which is quite a feat for the free Vox player on the little Macbook 12-inch I have.

[dalethorn]

4 minutes ago, esldude said:

I get an error saying the file can't be found on your link. 

 

Amazing how bad copy and paste is on these computers...

 

 

https://www.dropbox.com/sh/st6goiq1q0mjmsz/AACgOP4f6dQLD4m0KLWlb8yJa?dl=0

[mansr]

5 minutes ago, dalethorn said:

By my calculation, that would mean the player has to process 11.5 mb per second, which is quite a feat for the free Vox player on the little Macbook 12-inch I have.

That's only a little more than DVD bit rate. Mid-90s PCs could play DVDs, and that requires a lot more processing.

[mansr]

21 minutes ago, dalethorn said:

Amazing how bad copy and paste is on these computers...

 

https://www.dropbox.com/sh/st6goiq1q0mjmsz/AACgOP4f6dQLD4m0KLWlb8yJa?dl=0

Here's the spectrogram of that:

 

There's hardly any content above 5 kHz. No wonder it compresses well. This typical of piano music.

[esldude]

I converted to 24/88 with the Sonore software.  Works fine.  

 

The FLAC from the conversion was 39 meg.  Opening it and saving as a wav resulted in 78 meg.  So 50% compression which is about right for FLAC.  The 16/44 wav downloaded from dropbox was 26 meg which also is in line with a 78 meg wav in 24/88 form.  Considering the parameters of DSD64 being close to 96/24 in size the 100 meg size of it seems about okay too. 

 

Glad to hear a recording using the Isomike setup anyway.  Thanks. 

[dalethorn]

9 minutes ago, mansr said:

Here's the spectrogram of that:

 

There's hardly any content above 5 kHz. No wonder it compresses well. This typical of piano music.

 

If you would read my long post, it asks why:

 

1) The FLAC converter never went below 55 percent on thousands of other conversions.

 

2) JRiver's conversions to 24/88 totally corrupted my Foobar player.

 

3) My Foobar player plays over a thousand 24/88 to 24/192 HDTracks and other sites' downloads perfectly.

 

4) My Foobar conversion of a 128 k (or 320 k) MP3 to FLAC still makes a FLAC file several times larger than the MP3.

 

The "low resolution/content" does not explain any of the above.

[mansr]

The posted WAV compresses to 24% of original size using the reference FLAC encoder at level 5. A 16/44 WAV converted from the DSD file with Sox compresses equally well. Seems to me it's simply a music track that compresses unusually well.

[dalethorn]

5 minutes ago, esldude said:

I converted to 24/88 with the Sonore software.  Works fine.  

 

The FLAC from the conversion was 39 meg.  Opening it and saving as a wav resulted in 78 meg.  So 50% compression which is about right for FLAC.  The 16/44 wav downloaded from dropbox was 26 meg which also is in line with a 78 meg wav in 24/88 form.  Considering the parameters of DSD64 being close to 96/24 in size the 100 meg size of it seems about okay too. 

 

Glad to hear a recording using the Isomike setup anyway.  Thanks. 

 

So if I read this right, the only anomaly (based on the 1-4 post I just made) is the FLAC conversion from JRiver's 16/44 WAV file.

[dalethorn]

Just now, mansr said:

The posted WAV compresses to 24% of original size using the reference FLAC encoder at level 5. A 16/44 WAV converted from the DSD file with Sox compresses equally well. Seems to me it's simply a music track that compresses unusually well.

 

As I said many times, I have *never* had a legitimate WAV file compress less than 55 percent.  I even took a 128 k MP3, converted to WAV, then back to a FLAC several times larger than the MP3.  My FLAC encoder is doing something with JRiver's WAV that it has never done (and still does not do) with *any*other low-res file.

 

Compression is obviously not the issue.

[mansr]

2 minutes ago, dalethorn said:

If you would read my long post, it asks why:

 

1) The FLAC converter never went below 55 percent on thousands of other conversions.

Yes, 50-60% is typical. This piano piece is much simpler than average music and thus compresses better. I admit 24% is pretty unusual though.

 

2 minutes ago, dalethorn said:

2) JRiver's conversions to 24/88 totally corrupted my Foobar player.

That's obviously worrying. Could you share one of these "toxic" files?

 

2 minutes ago, dalethorn said:

3) My Foobar player plays over a thousand 24/88 to 24/192 HDTracks and other sites' downloads perfectly.

I'd hope so.

 

2 minutes ago, dalethorn said:

4) My Foobar conversion of a 128 k (or 320 k) MP3 to FLAC still makes a FLAC file several times larger than the MP3.

That's to be expected.

 

2 minutes ago, dalethorn said:

The "low resolution/content" does not explain any of the above.

What is the source of the DSD files?

[esldude]

Okay, I took your 44 wav file.  Compressed it to 24 bit Flac and about 45% size reduction.  When I compressed it to 16 bit I see what you mean.  The file size was 6 meg or so.  I also have never seen one compress that well.  I have played with FLAC before and signals with extremely low signal levels and curtailed highs will compress less than 50% though I haven't seen one compress this much.

[dalethorn]

4 minutes ago, mansr said:

Yes, 50-60% is typical. This piano piece is much simpler than average music and thus compresses better. I admit 24% is pretty unusual though.

 

That's obviously worrying. Could you share one of these "toxic" files?

 

I'd hope so.

 

That's to be expected.

 

What is the source of the DSD files?

 

The source is from NativeDSD I think - the recordings done by Ray Kimber, as featured in Stereophile.

 

If I can do so later on, I'll do a 24/88 conversion to FLAC using JRiver and upload it to Dropbox.

[esldude]

Okay, I took the 88/24 wav file from the Sonore conversion.  Opened it in Audacity, exported it as a 44/16 level 5 Flac.  The result was slightly larger than compressing your 44 wav file at 7 meg (your file compressed to 6 meg).  Still a smaller size than is the norm. 

 

I think mansr is correct, it simply is a file that compresses well due to no high frequencies and low noise levels in the recording. 

 

BTW, if you use the Sonore converter.  It has an option to adjust the output level.  Default is +4 db.  I find this to come close to matching PCM files of the same material.  This was 4db higher in level than your conversion there at 44 khz. 

[kumakuma]

I used XiSRC to convert both the DSF file and WAV files to 16/44.1 FLAC files.

 

The resulting files were 7.4 MB in size which is 28% of the WAV size. Both files played fine in JRiver. 

 

MP3 files (320 CBR) created directly from JRiver were 6MB in size. 

[dalethorn]

6 minutes ago, esldude said:

Okay, I took your 44 wav file.  Compressed it to 24 bit Flac and about 45% size reduction.  When I compressed it to 16 bit I see what you mean.  The file size was 6 meg or so.  I also have never seen one compress that well.  I have played with FLAC before and signals with extremely low signal levels and curtailed highs will compress less than 50% though I haven't seen one compress this much.

 

And don't forget, the free FLAC codec I have (2 versions) will create a WAV from any MP3 and then convert the WAV to FLAC, and the FLAC will be several times as large as the MP3.  Meaning: It's not a compressions issue.