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nobby
12-02-06, 03:41
I wanna compress my music on my psp...
I read that on the PSP you can greatly compress the MP3 file without the human ear even noticing a slight difference...

Little did the website even say were the frequency and bit rate...


Does anyone know what frequency and bitrate I should compress to, to get a smaller but NO noticable difference?
Mr Kot
12-02-06, 04:45
The human ear is more sensitive than you might think.

44.1 kHz and 16 bit will do nicely, bearing in mind that 44.1 kHz is the sample rate, which will reproduce a audible wave frequency of just over 22 kHz, which is marginally in excess of the human hearing range.

Having said that, if your ear can cope with a 15 kHz max frequency, a sample rate of 30 kHz will do fine.

Don't bother with anything less than 16bit or it will sound shite.
Lightpipe
17-02-06, 00:49
Also try using different mp3 codecs to create your mp3's, there can be a big difference in quality encoding at the same bitrate/sample rate..
jini
17-02-06, 07:40
mp3 codec @ 190kbps sampling and you will hardly listen a difference, even if you use audiophile earphones
calim
17-02-06, 11:09
What said Lightpipe is right. Quality at a same bitrate differ with the encoder, and also depend on parameter you pass to it... Basically if you compress to get quality, it will be longer ^^
For example, try LAME (http://www.rarewares.org/mp3.html) at 96Kbit/s and ask encoder to optimize for quality (not speed), you'll see the result is pretty good for that kind of bitrate :) (more close to certain encoder's 128kbit/s or more).
xyl_az
17-02-06, 11:20
uhm, well that really depends what kind of music you want to compress and what quality you want to have. For pop music 128-160 vbr should be enough, but for anything more advanced i would go at least for 190+ vbr. And if you really want to have cd-like quality, then 256 is absolute minimum i'm afraid
calim
17-02-06, 11:42
uhm, well that really depends what kind of music you want to compress and what quality you want to have. For pop music 128-160 vbr should be enough, but for anything more advanced i would go at least for 190+ vbr. And if you really want to have cd-like quality, then 256 is absolute minimum i'm afraid

ok, it depends on what you want to encode, but also on the quality of the encoder (how you configure it) and *how* compression artifacts are rendered...
some encoder render artifacts that are not really nice to the ear...