Help. SACD ISO to FLAC files are getting BIGGER.

elee532 · « **on:** 27 Feb 2016, 01:34 pm »

I'm using Foobar to convert SACD ISO to FLAC files. For example, I have a 3.5gb ISO. If I extract just the multi-channel tracks from that ISO, I end up with 6gb of files. I've tried the maximum FLAC compression setting, but it only mages a tiny difference.

What am I doing wrong?

Thanks!

Phil A · « **Reply #1 on:** 27 Feb 2016, 02:04 pm »

ISO files may contain various mixes (e.g. multi-channel, CD layer). I've used Foobar to convert DFF to WAV

Phil A · « **Reply #2 on:** 27 Feb 2016, 02:06 pm »

Are you trying to get 2-channel FLAC files?

Phil A · « **Reply #3 on:** 27 Feb 2016, 02:08 pm »

There are threads in places like - https://hydrogenaud.io/index.php/topic,90011.0.html

ted_b · « **Reply #4 on:** 27 Feb 2016, 02:09 pm »

SACD ISOS can contain large amount of compression (DST) in order to fit both the multichannel and stereo titles on it. Once extracted the DST should now be decompressed, and therefore larger.

Example: Budapest Festival Orchestra - Mahler 4 (ISO is 2.94GB)
Stereo title is 2.24GB
Multichannel is 5.62GB

And that's just DSD64. Let's say you then convert to 24/192 (a file format larger than DSD64)....those sizes increase even more, then get compressed by whatever FLAC setting you use.

For an experiment I converted the above stereo DSFs to 24/352.8k PCM (aka DXD) at compression level 5 and came up with nearly an identically sized folder, even after compression (2.14GB).

elee532 · « **Reply #5 on:** 27 Feb 2016, 06:32 pm »

Thank you both. So, it sounds like 6GB is about what I should expect when extracting the multi-channel tracks from an SACD ISO to individual FLAC files? Much larger than I would have expected.

I did just discover that if I change the sample rate for SACD in Foobar from 176,400 to 88,200, the FLAC file sizes are cut about in half. Conversely, I also see an option for 352,800 which I assume would increase my FLAC files by two-fold.

So, I guess the next question is... any recommendations for setting a sample rate when going from SACD ISO to FLAC?

I really just wish Kodi could handle the SACD ISO files. Make my life a lot easier.

ted_b · « **Reply #6 on:** 27 Feb 2016, 06:37 pm »

JRiver can read ISOs directly.

Yes, sample rate doubles, size doubles. Your best sample rate is what sounds best on your DAC, period. It's called the DAC's sweetspot, and although normally the highest it can handle, is does not always follow that logic. The clocks in the dac may prefer one sample rate family (44k vs 48k) over the other.

elee532 · « **Reply #7 on:** 27 Feb 2016, 06:44 pm »

Yeah, I like JRiver a lot, and that's what I had been using.

However, I'm now playing from my QNAP NAS. Unfortunately, the 10' interface on the QNAP app for JRiver doesn't seem to work.