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Rockbox General => Rockbox General Discussion => Topic started by: lordearl on December 28, 2007, 05:56:35 AM

Title: X5 File fomat choices....
Post by: lordearl on December 28, 2007, 05:56:35 AM
Hi Dudes (read: X5 users),

I assume most of you have been through a problem similar to this in the past - so I'd be interested to see your thoughts (can't really find a definitive answer no matter how much I search). I just managed to get my hands on a 20GB X5L & have the following requirements before rockboxing.

(1) Clearly, although 20 GB seems pretty large to most people, it will fill up pretty quickly if one uses a lossless file fomat.

(2) Any chosen file fomat must be gapless (fave music is segue driven alum rock - Pink Floyd, etc).

(3) Therefore, we need a lossy, gapless format. This clearly excludes mp3.

(4) The best lossy format (to my ears, anyway ;)) is OGG.

(5) OGG unfortunately provides the worst battery life, which is already impeded by the use of Rockbox in any case.

(6) So we come to the problem of needing a gapless lossy format which is preferable to OGG in terms of CPU usage, but doesn't lose out on the sound quality too much.

Anyone got any ideas/data?

Cheers!

PS -- Further to all this, would anyone advise not even trying the X5L with the original firmware so as not to be disappointed by the drop in sound quality by rockboxing (don't know whether this is a myth or not)?
Title: Re: X5 File fomat choices....
Post by: markun on December 28, 2007, 06:15:39 AM
Quote
... provides the worst battery life, which is already impeded by the use of Rockbox in any case.

I was told that the battery life with rockbox is more than what Cowon states in their manual. What kind of runtimes are you getting with the rockbox and the OF (original firmware) ?

Quote
... as not to be disappointed by the drop in sound quality by rockboxing

What kind of loss in quality are you hearing? Perhaps it's something that can be fixed.
Title: Re: X5 File fomat choices....
Post by: lordearl on December 28, 2007, 06:35:53 AM
Howdy Markum,

Sorry - I should have made my story more detailed (but I thought the post too long already!).

My X5 is in the box, unopened.  I'm deciding whether to rockbox it and not use the original firmware -- some reports over at headfi indicate that the sound quality with the original firmware is better than that of the rockboxed X5).

On the concern of battery life -- the data on this site shows up to 28 hrs for a rockboxed X5L, whereas COWON claims up to 35 hours with original firmware.
http://www.rockbox.org/twiki/bin/view/Main/BuyersGuide

Re the gapless problem - i assume for the gapless playback to work, we would need a gapless file format like flac, ogg or musepack.  mp3 is not inherently gapless, so despite the fact that rockbox enables gapless play, would it be right to presume we need a gapless format, too?

Title: Re: X5 File fomat choices....
Post by: LinusN on December 28, 2007, 06:42:31 AM
I have not yet heard a valid claim of loss of sound quality with Rockbox. Most claims of better quality with the original firmware have been about psychoacoustic bass enhancement, i.e the BBE Mach3Bass algorithm. That's not better quality in my opinion, since it alters the original audio.

Regarding battery life, we are today at least on par with Cowon, if not better.

Rockbox can play MP3 gaplessly, provided that the files are properly encoded with LAME.
Title: Re: X5 File fomat choices....
Post by: lordearl on December 28, 2007, 06:50:46 AM
Hmmm the plot thickens -- I thought LAME has, by virtue of its structure, a gap at the beginning and end of each file.

If it can play gapless, all the better as is presume MP3 offers the best of all lossy formats for battery life.

how does MUSEPACK go re battery life and sound quality?

re BBE Mach3Bass -- totally agreed, the complaints at headfi certainly surrounded this & I doubt this feature bodes well for orchestral muzak, etc!
Title: Re: X5 File fomat choices....
Post by: Febs on December 28, 2007, 08:28:07 AM
Hmmm the plot thickens -- I thought LAME has, by virtue of its structure, a gap at the beginning and end of each file.

This may answer some of your questions:  http://www.rockbox.org/twiki/bin/view/Main/IriverFAQ#Does_Rockbox_support_gapless_pla

This FAQ was written back before Rockbox even supported the X5, but it applies to the X5 as well as other Rockbox platforms.