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PencilNeckGeek
2010-05-31, 09:59
OK, here's the scenario. I have imported a CD into i-Tunes in .WAV file format. I have no volume leveling features enabled within i-Tunes and the final Bitrate on all songs is listed as 1411kbps within the i-Tunes window.

I have my Squeezebox Server setup to use i-Tunes. When I play one of the songs within the Squeezebox Web Console and look at the Song Info while it's playing I see the following info listed below:

Bitrate: 1411kbps CBR (Converted to 705.6kbps ABR)

Who can tell me the reason why the song appears to be down converted while playing? Is this a product of i-Tunes over stating the actual Bitrate to 1411kbps and the True Bitrate is actually 705.6kbps?

Also, on some songs I see a combination of the info listed above as well as this info below regarding the Volume:

Volume Adjustment: -5.49 dB (this value fluctuates up or down with the highest value observed so far as being -11.xx db)

Is this Volume Adjustment a product of the recording studio or something that the Transporter is doing?

I have the Transporter hard set to %100 volume at all times within the Audio Settings page. My fear is that I am losing Dynamic Range and sound quality as a result of this Bitrate & Volume adjustment behavior.

Is there a way to avoid this from happening? Would keeping all music in the Transporters native .flac format prevent this behavior? I'm wondering if by having these songs in .WAV format and forcing the Transporter to use some other, none native codec it is causing me to miss out on all the Bits I'm entitled to hear.

Thanks for any info you can provide

Phil Leigh
2010-05-31, 13:19
OK, here's the scenario. I have imported a CD into i-Tunes in .WAV file format. I have no volume leveling features enabled within i-Tunes and the final Bitrate on all songs is listed as 1411kbps within the i-Tunes window.

I have my Squeezebox Server setup to use i-Tunes. When I play one of the songs within the Squeezebox Web Console and look at the Song Info while it's playing I see the following info listed below:

Bitrate: 1411kbps CBR (Converted to 705.6kbps ABR)

Who can tell me the reason why the song appears to be down converted while playing? Is this a product of i-Tunes over stating the actual Bitrate to 1411kbps and the True Bitrate is actually 705.6kbps?

Also, on some songs I see a combination of the info listed above as well as this info below regarding the Volume:

Volume Adjustment: -5.49 dB (this value fluctuates up or down with the highest value observed so far as being -11.xx db)

Is this Volume Adjustment a product of the recording studio or something that the Transporter is doing?

I have the Transporter hard set to %100 volume at all times within the Audio Settings page. My fear is that I am losing Dynamic Range and sound quality as a result of this Bitrate & Volume adjustment behavior.

Is there a way to avoid this from happening? Would keeping all music in the Transporters native .flac format prevent this behavior? I'm wondering if by having these songs in .WAV format and forcing the Transporter to use some other, none native codec it is causing me to miss out on all the Bits I'm entitled to hear.

Thanks for any info you can provide

1) ignore the ABR bitrate figure - it is completely meaningless. Nothing is being downconverted.

2) you must have the iTunes volume levelling set, as that is the ONLY way that volume meta tags can be added to your files (unless you added them yourself afterwards... and I think you would know if you did that!). SBS reacts to these tags. You can turn this behaviour OFF at play time via the Settings - Player - Audio ... volume adjustment in the Web UI.


Using FLAC and avoiding iTunes would be a big step in the right direction to operational happiness :-) - however, from a pure audio quality perspective there should be no difference.

bhaagensen
2010-05-31, 13:21
Its probably because wav by default is streamed as flac. To change: Go to Settings > Advanced > Filetypes and look up the setting for WAV. Then disable all but the PCM (builtin) entry.

ntom
2010-05-31, 14:43
By coincidence just noticed the same thing on my standard Classic Squeezebox (playing through a separate DAC). I believe the Classic can't throughput 24/96 but downsamples at the server.

The track info for a 24/96kHz before it is selected for playing shows "Bitrate:3183kbps VBR". Once the track is actually playing the same info shows: "Bitrate:3183kbps VBR (Coverted to 705.6kbps ABR)".
This doesn't happen with 44.1 tracks so assumed this was an indication it has been downsampled.

If that's so, then maybe that's what's happening with your Transporter but if so there must be a setting somewhere to handle 24/96 without downsampling....!


As far as volume adjustment is concerned you must have volume levelling turned on somewhere in you ripping process -I replay gain.

PencilNeckGeek
2010-05-31, 16:12
Thanks for the replies. I will have to double check all the volume controls again and report back

mcvan
2010-06-10, 15:44
Thanks for the replies. I will have to double check all the volume controls again and report back
So what did you find out? I'm seeing the same thing w/ a 2604kbps VBR file that seems to get "(Converted to 705.6kbps ABR)" in a Squeezebox 3 Classic.

JJZolx
2010-06-10, 15:57
So what did you find out? I'm seeing the same thing w/ a 2604kbps VBR file that seems to get "(Converted to 705.6kbps ABR)" in a Squeezebox 3 Classic.

What is a '2604kbps VBR' file? What file format, bit depth and sampling rate is it?

By default, uncompressed lossless files (WAV, AIFF) will be _losslessly_ encoded in FLAC for streaming. Some (most) other lossless formats will be _losslessly_ transcoded to FLAC.

PencilNeckGeek
2010-06-15, 16:45
So from what I could tell I believe that the reason the volume was being adjusted on the CD's that were burned to .wav format via i-Tunes was because of the Volume Control lever that is shown at the top of the i-Tunes window. Even though the Preferences were set to not do any volume leveling.

I would typically keep the Volume setting within the i-Tunes window at about half way so my guess is that this was the reason I was seeing the Adjustment within the Squeezebox server.

As far as the bit-rate being lowered I will blame this on i-Tunes also as I believe it only burns with a Constant (ie..Hard Coded) Bit Rate but I could be mistaken about that.

I guess the moral of the story is to avoid i-Tunes like the plague when it comes to ripping your CD Collection. I recently switches over to DB-Power Amp for CD Ripping which seems much more accurate combined with it's Accurate Rip feature and no volume controls to worry about.

i-Tunes is the Devil......

andynormancx
2010-06-15, 23:25
I'm no fan of iTunes, but it sounds like you really don't understand what is happening here.

The volume control at the top of the iTunes window will have no effect on the tags added to your files to indicate any volume levelling.

The bit rate lowering also has nothing to do with iTunes. That it purely down to Squeezebox Server converting the audio to FLAC before streaming it to the player. This is a perfectly sensible thing to do (to reduce network usage) and the fact that it reports a "lowered bitrate" doesn't mean you have lost anything, FLAC is completely lossless, the same data will arrive at your player as was read from your CD with iTunes.

I'd agree that dbPowerAmp is much better than iTunes at ripping, but you are trying to blame iTunes for things that have nothing to do with it.

Phil Leigh
2010-06-16, 00:12
There is a lot of noise on these forums relating to the reported bitrate in SBS... which because of the transcoding is causing FUD.
I wish the bitrate displays for local music playback would be removed.
They really aren't helpful.

PencilNeckGeek
2010-06-16, 16:04
I'm no fan of iTunes, but it sounds like you really don't understand what is happening here.

The volume control at the top of the iTunes window will have no effect on the tags added to your files to indicate any volume leveling.


So if it isn't the volume control in i-Tunes then what else could it be? Would the volume control in Windows be the culprit to adding these tags? If it isn't Windows altering the tags either then you would be correct in stating that I certainly don't understand what is happening here.

One thing I know for sure is that all volume leveling is turned off in i-Tunes preferences and it was the only piece of software (Excluding Windows OS, of course)involved in getting the CD data into a .wav format.

JJZolx
2010-06-16, 16:45
So if it isn't the volume control in i-Tunes then what else could it be? Would the volume control in Windows be the culprit to adding these tags? If it isn't Windows altering the tags either then you would be correct in stating that I certainly don't understand what is happening here.

One thing I know for sure is that all volume leveling is turned off in i-Tunes preferences and it was the only piece of software (Excluding Windows OS, of course)involved in getting the CD data into a .wav format.

What difference does it even make? If replay gain is turned off (the default setting) for the player playing these files then it's not applied. It's just a piece of data that is ignored.

The WAV files probably don't have any tags. Information in iTunes about the files would be in iTunes' database, not file tags.

Phil Leigh
2010-06-16, 22:56
Can we start again?
You had 2 questions:

1) Why is the bitrate reported as lower than you think it should be - answer: by default FLAC is used as the streaming transport protocol to the player and that needs less bits than wav/pcm. It is still perfect fidelity. Forget about it.

2) Why does Replaygain information show up on the screen? - answer: the files you are playing have replaygain tags associated with them. They were put there by iTunes. If you have the "adjust volume" options turned off (settings - player - audio) they do nothing at all.

Personally If I had a Transporter i would not use iTunes for ripping CD's - it has no AccurateRip facility. Use DBPoweramp or EAC instead.