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View Full Version : Sound quality dramatically improved by removing iTunes and switching to FLAC



macsband
2010-02-08, 21:16
A year ago, I ripped my CD collection in Apple Lossless format via iTunes. With Squeezebox sending the music to a $2,000 amp+speaker system via digital connection, I expected beautiful music. I was disappointed. The sound was muffled and vague.

A couple days ago, I got tired of dealing with Apple's proprietary way of doing business, so I uninstalled iTunes and converted from Apple Lossless to FLAC. Now Squeezebox sends music in its native tongue, as it were.

AND THE SOUND IS SUDDENLY AWESOME!! It's like I have a whole new music library!! Now the amp + speakers are producing crystal clear, full, rich sound with live concert hall depth, harmonics, and brilliance.

Something I've never read in the Squeezebox literature or in this forum is that there must be a significant loss that takes place when SqueexCenter Server converts Apple Lossless to FLAC when sending Apple Lossless music files to Squeezebox. By dropping iTunes and converting the music files from Apple Lossless to FLAC (and switching to MediaMonkey as my jukebox), listening to my music has become a joy.

Just wanted to share this experience in case any other Squeezebox users have their music files stored in Apple Lossless. You may want to convert to FLAC!

dsdreamer
2010-02-08, 21:36
If the change was as dramatic as you describe, then I can only imagine a bad ALAC binary or misconfiguration of the file conversion pipe was to blame.

I assume you didn't re-rip your CDs? If not, you've just pre-converted the files off-line instead of having them converted on the fly. The results should certainly be the same either way!

Would you mind stating your SBS version and OS platform it is running on?

garym
2010-02-09, 04:47
Makes me think that bitrate limiting might have been turned on, and set to a low quality mp3. Seems I recall that LAME V9 (very low quality) was the default on bitrate limiting when I installed SbS. So perhaps he was accidentally listening to 32kbs files.

andynormancx
2010-02-09, 05:07
Something I've never read in the Squeezebox literature or in this forum is that there must be a significant loss that takes place when SqueexCenter Server converts Apple Lossless to FLAC when sending Apple Lossless music files to Squeezebox.
You've never read it because it doesn't happen. The conversion from ALAC to FLAC is 100% lossless.

If you hear a difference it is either down to some odd misconfiguration or because you just think you hear a difference.

macsband
2010-02-09, 08:42
My intention was not to improve sound quality because the literature states that lossless = lossless. I did not anticipate a change in sound quality. My intention was to get away from Apple's proprietary way of doing business. However several people have listened to the system before and after. The difference is not subtle; it's so dramatic that everyone immediately commented, even before they knew that I had made any change to the system.

SqueezeBox Server Version 7.4.1
Microsoft Windows XP Professional Service Pack 3 (updates current)

Player > Audio > Bitrate Limiting = No Limit

I re-ripped several CDs (classical and pop) and played the same track in different versions: the ALC version, the converted FLAC version, and the ripped FLAC version. There was a dramatic audible difference between the ALC and both FLAC versions. There was no audible difference between either FLAC version.

macsband
2010-02-09, 09:03
you've just pre-converted the files off-line instead of having them converted on the fly.

I guess I didn't make myself clear. This was the whole point of my post: pre-converting the files off-line instead of on the fly made a HUGE difference in sound quality.

Mac

dsdreamer
2010-02-09, 09:08
My intention was not to improve sound quality because the literature states that lossless = lossless. I did not anticipate a change in sound quality. My intention was to get away from Apple's proprietary way of doing business. However several people have listened to the system before and after. The difference is not subtle; it's so dramatic that everyone immediately commented, even before they knew that I had made any change to the system.

SqueezeBox Server Version 7.4.1
Microsoft Windows XP Professional Service Pack 3 (updates current)

Player > Audio > Bitrate Limiting = No Limit

I re-ripped several CDs (classical and pop) and played the same track in different versions: the ALC version, the converted FLAC version, and the ripped FLAC version. There was a dramatic audible difference between the ALC and both FLAC versions. There was no audible difference between either FLAC version.

Is there any possibility that your ALAC rips were not truly ALAC encoded?

I ask because both ALAC and AAC encodings go in the same .m4a container and it is possible to confuse the two.

If you had converted your files directly from ALAC to FLAC using dBpoweramp and gained sound quality from doing so, I'd have ruled out the mis-encoding question above, but you mention re-ripping so I have to ask...

Next, if you have two encodings of the same file, one of which sounds mediocre and the sounds good, then try listening to them both in another player with some good headphones. You have MediaMonkey installed, IIRC.

There is a chance that Replaygain or Soundcheck settings somehow are in play here.

If they still sound different in a software player, then I'd suspect the the encoding is wrong. If they only sound different when played back through a SqueezeBox system, I might begin to suspect the transcoding s/w binaries are not working as they should (but it's odd that others haven't noticed this).

ModelCitizen
2010-02-09, 09:18
If the Apple Lossless files were definitely streaming to the player as Flac (and not MP3) then there *should* be no difference all.

It is a bit worrying that you have heard some. A perceived difference in sound quality can sometimes come as a result of a volume change. It does seem unlikely, but could it be that the flac files are louder? One other thing that springs to mind is if the ALAC files were volume limited by Apple's equivalent of Replaygain (I know nothing about Apple proprietary formats or what a Squeezebox can do with them).

I'd be interested to know if your computer is particularly low spec?

It's not entirely uncommon that that people report sound differences between formats that really should sound the same, flac and wav (raw pcm) for instance. These reports always intrigue me.

MC

Phil Leigh
2010-02-09, 10:04
There's been a spate of similar posts recently and in all cases I believe something odd is going on with transcoding... can't get to the bottom of it yet...
It looks like usual suspects can be ruled out (prefs, lame). Seems to mostly involve some cross platform issue like mac formats on PC or PC formats on a NAS (I know - shouldn't matter)...

iPhone
2010-02-09, 10:20
A year ago, I ripped my CD collection in Apple Lossless format via iTunes. With Squeezebox sending the music to a $2,000 amp+speaker system via digital connection, I expected beautiful music. I was disappointed. The sound was muffled and vague.

A couple days ago, I got tired of dealing with Apple's proprietary way of doing business, so I uninstalled iTunes and converted from Apple Lossless to FLAC. Now Squeezebox sends music in its native tongue, as it were.

AND THE SOUND IS SUDDENLY AWESOME!! It's like I have a whole new music library!! Now the amp + speakers are producing crystal clear, full, rich sound with live concert hall depth, harmonics, and brilliance.

Something I've never read in the Squeezebox literature or in this forum is that there must be a significant loss that takes place when SqueexCenter Server converts Apple Lossless to FLAC when sending Apple Lossless music files to Squeezebox. By dropping iTunes and converting the music files from Apple Lossless to FLAC (and switching to MediaMonkey as my jukebox), listening to my music has become a joy.

Just wanted to share this experience in case any other Squeezebox users have their music files stored in Apple Lossless. You may want to convert to FLAC!

Important: When you stream Apple Lossless, what are your settings for that in the settings section of SBS? Is the Apple Lossless converted to MP3 or FLAC for playback? If they are being converted to MP3, that is why they sound inferior.

Anyway, the good news is that you have made the switch and moved away from iTunes and Apple encoding, congrats! My position is that FLAC is currently the way to go.

Phil Leigh
2010-02-09, 10:25
Important: When you stream Apple Lossless, what are your settings for that in the settings section of SBS? Is the Apple Lossless converted to MP3 or FLAC for playback? If they are being converted to MP3, that is why they sound inferior.



The default setting is stream alac native... isn't it?
Is there any way to get hold of an alac test file?

macsband
2010-02-09, 10:26
The ALC files were ripped with iTunes using its default settings for Apple Lossless. Over time, various CDs, (old and newly procured) were ripped using the current version of iTunes (most recently, version 9).

The FLAC files converted from ALC were converted by MediaMonkey using the default setting (compression level 6).

The FLAC files ripped from a CD were ripped by MediaMonkey using the default setting (compression level 6).

Because AAC and ALC files share the same .m4a file extension, care was taken to not confuse the two: AAC files were converted to MP3; ALC files were converted to FLAC.

MP3 files, even those at high bit rates (192 and above) sound less full than FLAC files, which is expected.

I'm not contending that ALC files inherently sound inferior to FLAC, so I don't see the point of playing them on a different player. The point of my post is that the loss apparently occurs when Squeezebox Server translates ALC files on the fly. I'm sure this was not by design. I had no suspicion that it might occur. It was the fact that it did occur that shocked me. I anticipated hearing NO DIFFERENCE between ALC files and FLAC files when I played them via the same Squeeze Box Server to the same audio system. My post was to document for the community, for whatever purpose it may serve, that I (and others) do in fact hear such a difference.

What difference would it make if the computer were particularly low spec??? It's the same computer and the same sound system. The only variable is the type of file being played. FLAC files sound better than ALC files WHEN PLAYED under the same conditions, i.e., via the same Squeeze Box Server streaming to the same audio system.

We're not hearing a volume difference. It's very difficult to provide good qualitative descriptions of what we hear. I can only repeat: the difference is dramatic and the difference is in detail and clarity and fullness, whether played a low volume or played at booming volume.

andynormancx
2010-02-09, 10:33
MP3 files, even those at high bit rates (192 and above) sound less full than FLAC files, which is expected.
Very, very few people can testably, reliably hear the difference between high bit rate MP3 and FLAC. If you aren't doing a double blind test (with a thorough check that the volume levels really are equal) to compare 192k MP3 and FLAC then I'm afraid you have no real idea whether you are really hearing a difference or not. The same applies to comparing your transcoded ALAC vs FLAC.

macsband
2010-02-09, 10:39
Important: When you stream Apple Lossless, what are your settings for that in the settings section of SBS?

The documentation I've read says that Squeeze Box Server converts ALC to FLAC for streaming to the Squeeze Box player. According to my understanding, this is necessitated by Apple's proprietary way of doing business. I use the default settings on SBS, so I assume that's what I'm getting. If not, why would the designers of SBS default to stream ALC as MP3 and not tell me??? It would be a very illogical choice, given that FLAC is available and more suitable.

But I'd be glad to check. Tell me where this setting is, please.

macsband
2010-02-09, 10:41
Very, very few people can testably, reliably hear the difference between high bit rate MP3 and FLAC.

Come by and listen for yourself. When played sequentially, the difference is obvious.

iPhone
2010-02-09, 10:46
The default setting is stream alac native... isn't it?
Is there any way to get hold of an alac test file?

Yes the default is Native, but that doesn't mean that is what it is set to now. If it was changed to Disabled (for whatever reason) then the ALAC could be streaming as MP3 which was my point for asking to check the actual settings. This setting would only affect the ALAC and have no affect on FLAC which could account for the audible difference.

Without being there, I thought it best to check even what one might assume.

andynormancx
2010-02-09, 10:50
Come by and listen for yourself. When played sequentially, the difference is obvious.

Not unless there is either something badly wrong with your high bit rate MP3s or you are one of those very few people who are blessed/cursed with an unusually exceptional ability to spot MP3 artefacts.

Phil Leigh
2010-02-09, 10:53
Yes the default is Native, but that doesn't mean that is what it is set to now. If it was changed to Disabled (for whatever reason) then the ALAC could be streaming as MP3 which was my point for asking to check the actual settings. This setting would only affect the ALAC and have no affect on FLAC which could account for the audible difference.

Without being there, I thought it best to check even what one might assume.

Understood.
Now you are going to think I'm bananas, but I've just converted a FLAC to ALAC and played them side by side (Touch, SBS 7.5 nightly standard convert.conf)
... and the ALAC is clearly quieter by about 2-3dB.

I have Replaygain OFF, but I notice that the flac and alac files have track gain of -3.18dB... hmmm...


EDIT: sorry - the FLAC has -3.18 track gain, the ALAC seems to have lost its replaygain tags...

iPhone
2010-02-09, 11:39
Understood.
Now you are going to think I'm bananas, but I've just converted a FLAC to ALAC and played them side by side (Touch, SBS 7.5 nightly standard convert.conf)
... and the ALAC is clearly quieter by about 2-3dB.

I have Replaygain OFF, but I notice that the flac and alac files have track gain of -3.18dB... hmmm...


EDIT: sorry - the FLAC has -3.18 track gain, the ALAC seems to have lost its replaygain tags...

Hey Phil,

If you have time, run those same to files against the Diff Program and see if the graphs line up or if there are slight differences. If you have time.

macsband
2010-02-09, 11:49
Important: When you stream Apple Lossless, what are your settings for that in the settings section of SBS? Is the Apple Lossless converted to MP3 or FLAC for playback? If they are being converted to MP3, that is why they sound inferior.

Squeeze Box Server > Settings > Advanced > File Types

Apple Lossless
Apple Lossless = Native
FLAC = ALAC/FLAC
MP3 = Disabled
PCM = ALAC


FLAC
FLAC = Native
MP3 = Disabled
PCM = FLAC

These are the default settings; they have never been modified.

Phil Leigh
2010-02-09, 11:50
Hey Phil,

If you have time, run those same to files against the Diff Program and see if the graphs line up or if there are slight differences. If you have time.

Yes I will do that - I've saved the ALAC file away for later. I may be imagining things... ADM will tell me.

ModelCitizen
2010-02-09, 13:15
What difference would it make if the computer were particularly low spec?
Your SqueezeServer in your computer transcodes an Apple file to a Flac. With a flac file it does no transcoding and streams the file as is. The transcoding could take a reasonable amount of the capacity of a very low spec machine, perhaps not leaving sufficient resources for other tasks.
As I said I am interested to get to the bottom of these occassional reports of sound differences between different lossless file formats so I was on a fact finding mission. Myself and others want to make dead sure that the differences are not caused by obvious but often overlooked things like volume and file type settings before devoting more time to the conundrum.

MC

macsband
2010-02-09, 14:06
The transcoding could take a reasonable amount of the capacity of a very low spec machine, perhaps not leaving sufficient resources for other tasks.MC

Dell Dimension 4600 with Intel Pentium 4 running at 2.8GHz

As this is the only task this computer performs, Windows Task Manager reports no other processes taking CPU time when Squeeze Box Server is streaming.