Decoder Source: CH3 http://www.70.nu/ch3/index_e.html
Version: v1.51 © 1999 Shinji Chiba
Price: free
Settings: see screenshots
Similar products: none
Verdict: Poor
VBR: All
Full file: Always
Major Flaws: Default "Hi-Fi" mode adds aliasing,
Audible low frequency problems with some files
Minor Flaws: Low level accuracy is poor
Output level: correct
1-bit relative accuracy: Fair
1-bit absolute accuracy: Fair

SCMPX is a free independent MPEG audio player and encoder/decoder. To convert files, simply click the convert icon (see screenshots for more details). The "Hi-Fi" mode adds distortion, so this was disabled for these tests.

SCMPX fully decoded all CBR files, and most VBR files, though there was a small skip at the end of one of the Lame encoded VBR files. It exhibited the 100Hz bug for lame encoded files, and also cut out at a number of frequencies during the sine-wave sweep, just like winamp 2.62.

Lame encoded files aside, SCMPX adds small errors above 15kHz to both channels of 128kbps encoded files. These are probably inaudible, but still undesirable. Finally, the low level mathematical accuracy of SCMPX, as revealed by the Least Significant Bit test is not as good as the best. The low level sine wave becomes more noisy when decoded by SCMPX than by one of the correct decoders.

For these reasons, SCMPX cannot be recommended as an mp3 decoder.

EXTRA NOTE: In "Hi-Fi" Mode, SCMPX would have been judged as one of the worst decoders on test. The audibility of the distortion added by the "Hi-Fi" mode depends on your system and ears. To some, it will sound like an improvement or brightening of the sound. To others it will sound as if the tweeter of their loudspeaker has been damaged.


SCMPX v1.51 in use
SCMPX v1.51 in use

About SCMPX v1.51
About SCMPX v1.51

SCMPX Waveout Settings
The waveout settings dialogue is called by right-clicking on the title "SCMPX". Though changing these settings could sometimes give random results, choosing the above options and then restarting appeared to prevent SCMPX from adding aliasing distortion to the signal.

Decoding mp3 files with SCMPX
To decode mp3 files, click convert, Multiple Files, Decode to wav (as shown above). Then click "Add", and select the files to decode. In the next directory viewer (which appears automatically) select the destination path for the wav files; finally click RUN to start decoding.

Return to the list of decoders.