1. Encoding speed test
Encoder
Name
Audioactive Production Studio Professional v1.54
Fraunhofer .mp3 Producer Professional v2.1
Fraunhofer MP3Enc v3.1
Sound Limit v2.5
SoloH mpeg Encoder v0.07a
BladeEnc v0.76
Xing MP3 Encoder v1.5
rJPa MPx Encoder v1.02
NOTE: All programs were given the same running conditions with no background or user activity taking place during encoding.
RESUME: The highest encoding speed was demonstrated by Xing based encoders, then follow Fraunhofer based encoders (except for MP3Enc 3.1), and the slowest are ISO based encoders.
2. Encoding quality test
Here is the result of quality test for 8 differents encoders. Compare the results with the original wav sound. See what happens after 16000 and 20000 Hz.
RESUME: Absolutely linear frequency response was demonstrated by most ISO based encoders (except for BladeEnc 0.76). Tests results of new Xing encoders based upon VBR engine also allow to recommend their using for professional encoding.
* Fraunhofer based encoders are recommended for Internet oriented lower bitrates encoding (128 kbps and less), ISO based encoders are recommended for professional oriented higher bitrates encoding (192 kbps and more), Xing based encoders are usually used in home PC with cheap speakers by people who do not care for sound quality at all.
** NOTES:
People often ask "Which is better - Audioactive, Opticom Mp3 Producer Pro 2 or the Radium external codec release?" The answer is they will all sound the same since they all use the same encoding routines. The Radium codec has an advantage in that its a bit faster, but Audioactive is still very good and has a great interface.
**** All tests were performed at 128 kbps, with the highest CPU priority and HQ or VBR options on (where available), the input sample was 44,1 kHz, 16 bit stereo.
***** 'White noise' is called a sound form where all frequencies are represented equally.