The Benefits of Analog Tape Layback When Mastering from Digital Sources
Almost all of the projects that are sent to me for music mastering are recorded and mixed in the digital domain. Prior to mastering the music often has an edgy, harsh, linear, flat, thin, or that DAW in "the box sound". At this point, a warming up or adding that fat analog tape sound is usually needed to remove the edgy harshness found on many digital recordings of today. This type of procedure in mastering is called "laying back to tape" or "layback mastering".
This process is used on many major label recordings during the mixdown portion of the album at the recording studio or at the mastering session thus creating that "major label sound". When transferring the music to be mastered to stereo 2 track recorder with ½"analog mastering tape, the saturation process now starts to occur. The first thing that is noticeable is that the higher frequencies in the music start to have more of a pleasing sound. This is due to the fact that the audio waveform is compressed or saturated by the tapes physical properties. The peaks in the music are now more rounded and smooth rather than clipped or sharp. This helps to remove the edgy and harsh tones from digital recordings in a way that is pleasing to the ear.
In addition, the lower frequencies will also be enhanced. In the lower frequency range from about 50 Hz up to 200 Hz the music will also be slightly compressed and saturated, giving the music the fatness and warmth that only analog tape can provide. This same process also occurs to the mid-frequencies. First and foremost are the vocals. When comparing from the digital source to the analog tape the vocals will now have a richer and warmer tone to them and will seem to sound "fuller" as a result.
Another benefit is to the drums. With tape compression, the drum hits are much more even and the cymbals will appear to be less harsh and brittle. You may have some concerns about tape noise or "hiss." let me assure you this will not be the case. By incorporating a Dolby 363 SR noise reduction unit with our meticulously aligned and maintained Ampex mastering recorder with ATR audio tape this is just not an issue. I know that for some of you this may be a new concept, but I have been working with tape since the 70s and let me tell you "Nothing Sounds Like Tape".