Even more bitrates for Hi-MD walkmans?

[MDfreak]

With the introduction of SonicStage 3.3 Sony introduced the 352 kbps ATRAC3plus bitrate for playback on all Hi-MD walkmans. Strangely enough other bitrates introduces with SonicStage 3.2 like 320 kbps or 128 kbps still are converted by SonicStage.

So because nothing changed to my MZ-NH700 and RH10 the ability to playback the 352 kbps was available from the beginning in all Hi-MD's. So after debating with some people I've come up with a theory:

In all Hi-MD walkmans there is a "general" ATRAC3plus decoder that can decode every available bitrates. The only thing the decoder has to know which bitrate a file is to be able to decode it. So every Hi-MD is able to decode all bitrates as long as it knows which bitrate is used in a file. This is done in most video-codecs where you can freely choose almost every bitrate according to which quality you want. The decoder doesn't have to have a separate decoder for every possible bitrate but has a general decoder that handles every bitrate.

So the only thing Sony had to do with SonicStage 3.3 is "unlocking" different bitrates for the users. In SonicStage 3.2 they unlocked 320, 192, 160, 128 and 96 for encoding (but not for transfering). In 3.3 they added 352 and also unlocked the possibility to transfer that bitrate to Hi-MD.

So my assumption is that somewhere in the SonicStage code there is a list that tells SonicStage which bitrates and codecs can be transfered to particular devices. E.g. for my NH700 that would (with SonicStage 3.3.) be:

- ATRAC3 @ 132 and 66 kbps

- ATRAC3plus @ 352, 256, 64, 48

- PCM

For my RH10 Mp3 would be added.

If this is all true all Hi-MD's are also capable of decoding the other ATRAC3plus bitrates: 320, 256, 192, 160, 128 an 96 kbps but SonicStage doesn't allow this bitrates to be transfered to the Hi-MD's.

So now a request to you all: what do you think of my theory? And if it is true, is someone capable of "unlocking" the other ATRAC3plus bitrates for transfering to Hi-MD by "patching" SonicStage??? It would be great to get e.g. a 192 kbps ATRAC3plus file on a Hi-MD to test if it also can be played.

Edited November 2, 2005 by MDfreak

[Syrius]

I think that the 352 is more of some serious technical Voodoo Sony is pulling off on all Hi-MDs, rather than an unlockable option. Otherwise we'd be able to play the 320 and 192 bitrates since the last release of SS.

[MDfreak]

I think that the 352 is more of some serious technical Voodoo Sony is pulling off on all Hi-MDs, rather than an unlockable option. Otherwise we'd be able to play the 320 and 192 bitrates since the last release of SS.

The display of my NH700 and RH10 clearly show ATRAC3plus 352 kbps. So no "misuse" of existing bitrates. I think Sony didn't unlock the other bitrates earlier to keep the consumer from getting confused with all the bitrates.

For my study I'm kind of into audio/video coding and equipment and I can't think of any "voodoo"-trick that might be used to enable the playback because the music is also identified as 352 kbps by the player itself. If it would state e.g. 256 kbps Hi-SP than Sony would have pulled of a trick to misuse existing bitrates.

It is also the easiest way for Sony to make the diffences between first and second generation Hi-MD's: add the mp3-bitrates to the list of "accepted" bitrates for second-generation Hi-MD units. A first-generation can handle a disc with mp3's perfectly although it says "cannot play" because it detects a totally different codec used to create the file and it doesn't have the possibility to decode it.

So if my theory is right it would also be possible to "unlock" the mp3-transfer for first-generation Hi-MD's (although they cannot playback the mp3's). In that way I would imagine using my first-gen NH700 to create Hi-MD discs (and permanently hook it up to the computer) and use my RH10 to listen to the mp3-music.