West of Scotland Hi-Fi Club
2011-2012 season
West of Scotland Hi-Fi Club2011-2012 season
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| MP3 EVALUATION NIGHT OCTOBER 15TH 1999 First of all we encoded into separate wave files 2 tracks from a CD, one classical and one a popular track with vocals etc, and then trimmed them both to around a minute. I then compressed them to 15 tracks each of different MP3 bitrates ranging from 320 Kbits/sec to 16 Kbits/sec. I then shuffled the tracks around so no-one was aware which was coming next and then I issued a chart to fill in with the following answers:-
A comprehensive listening test for MP3 is the only true way to evaluate a compression system like it, and that's just what we did:-
Hardware:- 250Mhz PC with a Creative Labs Soundblaster live 256 sound card. Hoontech SPDIF output board. DacMagic3 D/A converter. Quad 44 pre-amp and LS5/8 active speakers Software:- Xing MP3 player with Audio Catalyst 2 compression software.
The chart above is the average results of the member’s tests, but as you can see 25 would have been the value assuming perfection. The results show that a consistent high quality is achieved right down to 128 Kbits/sec. After that the quality gets really poor, but as you can imagine that the original one minute file is 13.7 Meg and the 128 Kbits version is 1.245Meg, then the ratio of 12:1 near CD quality holds. Check out yourself the following two tracks at 128Kbit/sec and e-mail me what you think of the quality. By the way we all went to ANDIAMOS Italian Restaurant on the night. Very Tasty. ( Sorry Gordon)
Download the Classical track Duration 1 min - size - 909k
Download the Popular track. Duration 1 min 20secs - size -1.2M Back to Top
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Copyright Alistair Biggar
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