Bug 2684 - Implement De-emphasis
: Implement De-emphasis
Status: RESOLVED WONTFIX
Product: SB 2/3
Classification: Unclassified
Component: Audio
: 65
: All All
: P2 enhancement with 2 votes (vote)
: ---
Assigned To: Richard Titmuss
:
Depends on:
Blocks:
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Reported: 2005-12-05 20:44 UTC by Jim
Modified: 2008-02-08 23:34 UTC (History)
1 user (show)

See Also:
Category: ---


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Description Jim 2005-12-05 20:44:51 UTC
Contrary to popular belife some modern CD's (classic) still come with the RedBook standard "pre-emphasis" flag on the CD tracks.  It was found on some pop/rock CD's mostly before 1986.

Ripping these CD's with EAC, and then playing through the Slim hardware does not sound the same as from a CD player.

Only solution at the moment is to apply a software deemphasis on the audio file itself, and thus destroying any notion of it being lossless.
Comment 1 Jim 2005-12-05 20:46:15 UTC
P.S.  See this thread for some background/comments: http://forums.slimdevices.com/showthread.php?t=18738
Comment 2 Blackketter Dean 2006-04-21 21:03:48 UTC
Not sure if we have the CPU power to do de-emphasis, but it's worth examining.
Comment 3 Dan Sully 2006-08-04 16:38:36 UTC
Untargetting for post 6.5 assessment.
Comment 4 Chris Owens 2006-08-16 15:00:27 UTC
Dean asserts we do not have the CPU available to do this.
Comment 5 Roger Magnusson 2007-07-18 02:17:56 UTC
Does the Squeezebox have the ability to set the Preemphasis flag on the digital outputs? That would be the natural way of dealing with this I think. Then de-emphasis would take place in my receiver or separate D/A automatically. This is one of the biggest flaws (that and no fast forward with flac+cue...).

So far pre-emphasized CD:s in my collection are: 
Pink Floyd - Wish You Were Here (1975, Japan)
Pink Floyd - The Wall (1979, Columbia)
Dire Straits - Alchemy (1984)
Electric Light Orchestra - Discovery (1979)
Electric Light Orchestra - Secret Messages (1983)
The Beatles - Abbey Road (Japan)
Toto - Turn Back (1981)
Toto - IV (1982)
Toto - Isolation (1984)
Genesis - Genesis (1983)

All these sound horrible through Squeezebox, and performing de-emphasis in the digital domain is a bad idea.
Comment 6 Mike Walsh 2008-02-08 23:34:05 UTC
i had a denon cd player that on the display indicated if the cd had emphasis or not.  that was many years ago.

since then i have ripped literally thousands of cds with eac.

how would i even know if a cd had it?  and if it did, if i rip to mp3 with eac is it still there?

basically how does one handle this issue?

and if a cd player can handle it on playback, perhaps new SBs should add the same chip to do so as well.