Sony Ericsson K750i MP3 Bitrate Limitation

2006-06-25 12:13:43

Hello!

As you can read on the Sony Ericsson page, the K750i is supposed to support playback of MP3 files, but SE specifies that only up to 192 kbps for local playback - whatever that is supposed to mean. So, I assumed that MP3s with 224 kbps or higher would not work. Today, I wanted to test this and encoded a file with LAME and -V0 --vbr-new and one with -b 320. Both files worked flawlessly on my cell phone.
Now my question - can anyone who has this cell phone confirm SE's statement?

Regards,
Sebastian

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #1 – 2006-06-25 12:56:53

Just tried with a 256 kbps (CBR) file and there were no problems with playback.

Edit: ....and a 320 kbps (VBR).

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #2 – 2006-06-25 13:19:07

No problems with high bitrate VBR. For best MP3 performance, make sure you have the latest firmware. Check your current firmware by pressing these keys: > * << * < * , then Service-Info -> Softwareinfo

Firmware changelog and how to flash (german).

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #3 – 2006-06-25 14:01:30

Thanks for the information guys.

BTW, there seems to be a bug since R1BC002 which causes the player to ignore tags in M4A files. That certainly worked with earlier versions. I wrote to SE, but they keep saying that the problem is caused by a software update that went wrong.

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #4 – 2006-06-25 14:49:42

I don't suppose anyone has an idea how to update the firmware on a k750i under OS X ?

I tried using Virtual PC but it just hung at the turn off/remove SIM/Replace battery/hold C/insert cable window.

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #5 – 2006-06-25 16:05:32

AFAIK, you can only use SEUS on Windows 2000 and XP. You could update your phone on a friend's PC if he uses Windows.

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #6 – 2006-06-25 16:49:22

No problem playing APS/APX files and V4 --vbr-new on my W800i here ...

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #7 – 2006-06-25 19:08:08

Hmm... Wondering why SE claims that their phones support bitrates up to 192 kbps only.

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #8 – 2006-06-25 19:50:03

My impression is, that the Sony Ericsson manuals are generally poorly written. Maybe the first firmware versions were unable to decode bitrates above 192, or they are trying to suggest a lower bitrate this way.
My brother has a K300i that supports mp3 ringtones, if he gets a PC cable i'll try wich bitrates are supported. (My prediction is that nothing above 128, maybe only 32)

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #9 – 2006-06-26 00:41:55

Possibly unrelated, but I've used two different (recent model) Sony DVD players that specified a limited bitrate for MP3s they could play. I think it was 128 kbps (neither of them supports any tags too). They've never had a problem with -V 0 --vbr-new, except for tracks only a few seconds long, which cut out, or don't play at all (discovered when I created a disc of bird calls).

Edit: Ignore that. My memory's rubbish, all the tracks were 32 kbps. They must have just been too short for the players.

Sony Ericsson K750i MP3 Bitrate Limitation

Reply #10 – 2006-07-13 19:18:02

I have the K750i myself. Also with the current firmware R1CA021 it does not read .m4a, or .mp4 tags. There was no problems when doing the fw-update.

I find mp3 playback particullary good and use lame -V6, but also -V2 files works perfectly.

What are your experiences with mp4 playback sound? I was curious how to encode mp4's with similar quality as lame -V6? IMO, NeroAacEnc -q 0.3 sounded crap in comparison to lame -V6. I did some "blind tests" with .wav, .mp3 and .mp4 copies and used random playback mode.

So I wonder if aac-he files does not playback properly with the phone. I suppose -lc should be specified?