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daleyb
05-31-2015, 10:30 AM
Dont Like dragging this one back up- its been discussed a few times before...But Can I take that If I use Level 5 (default setting) to rip via Flac- playback is fine.I kinda get the impression that if I Even go to Highest level..The sound difference is Minimal..unless I have Supersonic hearing There no point in as the compression rate is So minor (and at level 5 -it also saves space..)

There was one person on forum using level 6 (Cant see a lot of point there..) But maybe he/she knows something I dont. I was thinking of being a bit album selective- by choosing 5 for albums Iam not that keen on..Then Highest for my Favourite Cds. (but again maybe this is pointless).

If I had streamer I could do a A/B comparison-but don't have that luxury yet...But dont want to regret anything further down the line...

garym
05-31-2015, 12:15 PM
Dont Like dragging this one back up- its been discussed a few times before...But Can I take that If I use Level 5 (default setting) to rip via Flac- playback is fine.I kinda get the impression that if I Even go to Highest level..The sound difference is Minimal..unless I have Supersonic hearing There no point in as the compression rate is So minor (and at level 5 -it also saves space..)

There was one person on forum using level 6 (Cant see a lot of point there..) But maybe he/she knows something I dont. I was thinking of being a bit album selective- by choosing 5 for albums Iam not that keen on..Then Highest for my Favourite Cds. (but again maybe this is pointless).

If I had streamer I could do a A/B comparison-but don't have that luxury yet...But dont want to regret anything further down the line...

NO, NO, NO, NO, a thousand times NO. There is NO difference in potential sound quality based on compression level of a FLAC file, not matter how good your hearing, or a computer that is designed to detect sound quality down to a million trillion levels of perception. Whether encoded as a 0, 5, 8, etc., a FLAC file will decode to the exact same bit perfect audio file for playback. Any problems with this decode process (which is either your server or player doing the decoding) would not be subtle changes in sound quality, but errors in the playback (that is, file won't play!).

I think you are missing the point that the encoding compression is simply how small the file is made when it is encoded *into* FLAC. But any FLAC file, encoded at any level, 0-8, will have to be *decoded* from that FLAC file back to the ultimate file that is PLAYED, and that ultimate file will be bit perfect back to the original CD you ripped it from,** regardless of whether you encoded the FLAC as 0, 5, 6, 8 or whatever.

**assuming of course your original rip produced a bit perfect file, but of course this question is entirely independent of the compression rate used on the FLAC file.

schmidj
05-31-2015, 12:33 PM
The compression in FLAC at all "levels" is not psychoacoustic like mp3, m4a. it is mathematical and fully reversible, like zip for documents or data files. If you zip a document and then unzip it, it doesn't leave some of the letters out. If you convert a PCM (.WAV) file to FLAC, all the bits are still there, just stored in a more efficient manner. Zip will work with .wav files also, but you'd have to unzip the file before your player would recognize it, players that recognize FLAC files are essentially "unFLACing" them before playing them inside the player. Also the FLAC encoder is optimized to better reduce the size of the particular bit patterns that occur commonly in PCM data than zip. Unless your player is badly broken, the bitstream presented to the digital-to-analog converter in your playback device is identical for FLAC and.WAV.

A simple example of this compression, lets say there are a string of 20 "0"s in the bitstream. The FLAC (or zip) encoder will look at that and replace it with a shorthand code functionally like (20:0) which is a lot shorter than 00000000000000000000. The decoder sees that code and puts all the zeros back in. The FLAC encoder is particularly optimized to find long bit patterns that tend to be repeated often in PCM waveforms, and replace them with shorthand abbreviations.

The different higher levels of FLAC simply spend more time looking for what it expects to be less common bit patterns in the PCM data to replace with shorthand abbreviations. .WAV is basically PCM, Pulse Code Modulation - which is what comes out of an Analog to Digital Converter - made into a computer recognizable file. So the trade-off is not for audio quality versus size, it is for processing time versus size. And that processing time is almost completely on the encoding side, which is not a real-time process anyway.

As others have pointed out here, the whole discussion of FLAC levels is now academic unless you have a very very slow processor (then use level 1) or are putting your FLAC files on a memory stick to play in a portable device (then use FLAC 8). At this point you might say "storage is cheap, I'll leave them as .WAV files, direct encoding of PCM" There are at least two issues: One of the biggest advantage of FLAC is that it plays well with metadata. Now you can actually add metadata to .wav files, one of the dBPoweramp DSP codecs does that very well, but much of the software in existence doesn't recognize it or deal well with it. mp3tag and many other tag editors won't edit it. The tags are an integral part of the FLAC specification, and most players will use them, or at least some of them. The second issue: Some players, particularly stand-alone players can't play .wav files, particularly at greater bitdepths or higher bitrates. My Yamaha receiver plays FLAC fine, 16 or 24 bit 44.1. It occasionally hiccups with 16 bit 44.1 .WAV files, and won't play 24 bit 44.1 .WAV files at all.

I also think it is easy to obsess too much on audio quality in this day and age. Any recorded audio, analog or digital, is "compressed" or at least different from the original acoustic image. To start with any microphone has limitations. No two microphones sound exactly the same. There are differences in frequency response, noise, distortion, linearity, and furthermore for a given mike there are significant differences depending on what angle the sound source is to the microphone. Then the capture and storage system makes compromises. It captures a limited frequency range, with a limited signal-to-noise ratio with distortion and non-linearity particular to the particular device as well as the type of device (say analog tape versus digital storage). The mixing engineer now processes it much more by the very process of mixing, where (s)he varies the levels of the different microphones, changes the EQ, changes the dynamics, adds reverb, (nowadays may pitch shift the singers voice to correct off key singing) or whatever. Good mixing engineers are looking to make an end product that they (and the producer) think sound good, not in most cases a transparent copy of the sound in the recording studio. You should think the same: Is it pleasing to my ear? Not "is it 110% accurate", whatever that is.

Also you have to think of the listening environment. What I want to hear inside my living room is very different than in my car, or with headphones and an Ipod or phone. An example: Some of you may know I have a large collection of Caribbean music, including a lot of steelband recordings. I also do quite a bit of my own steelband recording. You may not be aware but steelbands are known for playing classical music, at least in the Caribbean, and quite a bit of it has been recorded. Now there is a tremendous difference in sound pressure level between a quiet part with one pannist (the correct name for a steel drum is a pan or steelpan) playing softly, and the entire 60 to 120 musician orchestra playing loudly. Many of the recordings have captured that with a minimum of dynamic compression. Now that sounds great when played in my living room. In my car, the same recording consists of long periods of silence (the solo pannist is well below the road noise) followed by periods of deafening loudness. The processing of the recording needs to match the listening environment.

Enough for now. Enjoy the music, don't fret the details.

daleyb
05-31-2015, 01:02 PM
Thanks Garym as always ( a Thousand Thanks)... and WOW schmidj ...Thats Some Info..... Looks like 5 is the Magic Number!

garym
05-31-2015, 01:45 PM
excellent post schmidj!

BrodyBoy
05-31-2015, 02:36 PM
Dont Like dragging this one back up- its been discussed a few times before...

Is has....many, many times before. And to be honest, the question you posed suggests that maybe you haven't read any of that discussion.

A suggestion: Many of the issues and questions one might have as they delve into the world of digital music have indeed been brought up and discussed here. Before starting a new thread for every question you think of, you might consider doing a quick forum search on it. Not only will you find fast answers to most of your questions, but in reading previous discussions, you're apt to pick up a lot of information you hadn't even thought to ask about yet! :) I find it to be the best, most efficient way to learn about stuff like this.

mville
05-31-2015, 09:36 PM
A suggestion: Many of the issues and questions one might have as they delve into the world of digital music have indeed been brought up and discussed here. Before starting a new thread for every question you think of, you might consider doing a quick forum search on it. Not only will you find fast answers to most of your questions, but in reading previous discussions, you're apt to pick up a lot of information you hadn't even thought to ask about yet! :) I find it to be the best, most efficient way to learn about stuff like this.

Agreed. Search and read the forums for an answer/solution, before posting.

Dat Ei
06-01-2015, 02:17 AM
A suggestion: Many of the issues and questions one might have as they delve into the world of digital music have indeed been brought up and discussed here. Before starting a new thread for every question you think of, you might consider doing a quick forum search on it. Not only will you find fast answers to most of your questions, but in reading previous discussions, you're apt to pick up a lot of information you hadn't even thought to ask about yet! :) I find it to be the best, most efficient way to learn about stuff like this.

More than +1!!!


Dat Ei