InSync reader Tom P submitted the following rebuttal to our recent tech tip on CD audio extraction (see inSync 3/26/99).
“We have done listening tests with regard to loss of quality, and there is a loss on our computers. We’ve tried extracting (using Toast Audio Extractor 2.1) on the internal CD ROM drive, as well as the external CDR drive. The extracted files always sound smaller and less vibrant than the same files “played in” via a CD player (the Marantz 610) with digital out. Loss of bass and loss of soundstage width are the main complaints we have. We used to record right to CD (via the Marantz CDR) from the digital out of the Apogee AD1000 so we could extract the files into a hard disk system for mastering (we have already put the apogee’s UV-22 filters on the “mild” setting which is more forgiving of later processing). Now, we play the mixes into the hard disk software in real time, and the masters sound fuller! We thought that the 24X CD ROM drives in our Mac G3’s were to blame, but when we used the CDR’s, which read at 4X, the results weren’t much better! Just something else that engineers can’t take for granted…”
It sounds to me like you may be getting the resulting audio output from whatever CD ROM drive you are using. As you know, most CD ROM drives have D/A converters and audio output capabilities. Some programs cause the CD to play in real time while the software uses the A/D converters in the computer to digitize the audio and save it to the hard drive. This is not true audio extraction, but it looks like it is. The only other thing that could affect the audio quality is the difference caused by playing the CD back through the error correction circuitry of the CD player you normally use to input audio. Perhaps the error correction or some other attribute of the D/A conversion in the CD player is affecting the sound in a favorable way. There really is no other way I can think of to explain the sonic differences. It has to be one or the other.