48Khz MP3's

Posted by: JaBZ

48Khz MP3's - 14/01/2002 04:44

I have some Minidisc's I want to remove the music from, and remembered why they were supposed to be superior to CD's, due to the high freq rate 48KHz, which brought me to this interesting question...
I don't have a 48KHz snd card in my PC, i.e SBLIVE etc..
so playing these mp3's(320kbps 48KHz) I can detect a noticable Hiss, how does the EMPEG cope with 48KHz MP3's? anyone notice a hiss?
I am unable to test it at this moment.

cheers,
Jaidev
Posted by: rob

Re: 48Khz MP3's - 14/01/2002 08:25

It down-samples to 44.1Khz (which is the fixed rate in the DSP). There shouldn't be any hiss - that implies a poor down sampling routine (which doesn't surprise me in a PC application).

Rob
Posted by: synergy

Re: 48Khz MP3's - 14/01/2002 08:38


I can detect a noticable Hiss, how does the EMPEG cope with 48KHz MP3's? anyone notice a hiss?


I have a couple that I have made via DVD Rips (straight digital via the tools that the MPAA doesn't want anyone to have).

Empeg plays them without any problems, with no artifacts that my ears can hear. Certainly no hiss.

I'd say your sources have the problem. Also, I'd never say that a minidisc is BETTER than CD, as they use ATRAC lossy compression. Depending on the version of ATRAC that was used to encode the disc, it may be very close to CD quality, even perceptably the same, but I don't know of anyone that would say it was better. And earlier ATRAC wasn't very good anyways.

Posted by: SE_Sport_Driver

Re: 48Khz MP3's - 14/01/2002 08:47

I'm confused... MiniDisc (at least back when I was really into them) used ATRAC encoding and not MP3. Also, any input (be it 48khz from DAT or 32khz from DSS) was converted to 44.1khz to be put on the MiniDisc.

As far as I know, all MiniDiscs are 44.1khz, 16bit. You can get high end decks that have 24 or 32 bit processing (I think - probably in the DAC) but that doesn't effect the files on the disc.

Minidisc was never touted as being superior to CD's. Only more convienient. Becuase of their encased platers, there is little risk of getting the surface dirty or scratched. And they are so small. Minidisc is a "lossy" compression, so it's audio could never exceed that of it's source. It was meant to "compliment" CD's and replace the audio casssette.
Posted by: Chao

Re: 48Khz MP3's - 14/01/2002 10:26

Heh. Took the words right out of my mouth , SE. The funny thing is, the source material was probably upsampled to 48K to begin with, then downsampled back in the playback. The artifacts on that mp3 are going to be numerous

Oh, and BTW, i'm sure your player program doesn't interpret the frequency in software, so if you're hearing audio, your sound card *does* do 48khz.

That said, Minidiscs are fun for on the go sampling with a stereo mic. Pretty pretty soundscapes with no HTRF filtering needed!