From Mix magazine: MASTERING: From LP to MP3

Feb 18, 2009 6:53 PM, By Janice Brown

           
 

MASTERING FOR MULTIPLE RELEASE FORMATS

As far as mastering to both CD and vinyl, Gold echoes the practices of Kutch, Sax and Wells, noting, “If I'm mastering the record [for CD], I always cut off a 24-bit un-peak-limited file, but otherwise the master I make for the CD is the same as the master I cut.” Special circumstances do come up, says Gold, where the dual-format mastering is not so seamless. “I've mastered records of experimental music, and sometimes there will be elements like superwide stereo bass, which is very difficult to cut onto a record,” he notes. “So I may do two versions of that, but that's the really odd case.”

When planning for a vinyl release, artists need to count on significant manufacturing time, adds Calbi. “The jacket manufacturers and pressing plants are so overwhelmed now that there's a huge turnaround time. There's just more demand than there is supply, especially for high-quality pressing, but even just the raw materials.”

Realities of MP3

As the lowest-quality release format, the lossy-compressed MP3 or AAC audio version of the record will not be the focus of any mastering session. Clients may ask about optimizing for MP3, custom encoding options and the digital distributors who support them, but by and large, the mastering process does not deepen, technically, to prepare the material for its inevitable digitization.

“There is a conversation, sometimes, about how to optimize for MP3, but it's really not part of the mastering process for me,” says Calbi, “because I don't want to master for a dumbed-down file. I master for 16-bit/44.1.”

Stubblebine shares, “We don't really do a separate mastering for MP3s, but assuming the CD is going to be used as a source for the MP3 or AAC file, my main consideration is that what makes it sound good for the CD makes it sound good for the download, as well.

“The biggest thing we can do to make sure the download sounds as good as possible is to resist the temptation to squeeze it too hard,” Stubblebine continues. “Once everything gets squeezed into the top 2 dB of the dynamic range, when you turn that into an MP3 or an AAC, what comes out pretty much sounds like noise. But if you can leave a little bit of dynamics in it, then even the lossy-compressed version sounds more musical.”

While artists, producers and certainly mastering engineers may be interested in some higher-quality digital format, the distribution channels for a higher-resolution digital download are just not there yet for the mainstream music market. Wells has been “kicking the tire of digital distribution and fidelity of digital assets” for the past five years, even researching and writing on the topic. Finally, this year, he's seeing clients take an active interest in their digital assets and how they can optimize sound quality and find distributors who at least accept custom-encoded audio files, a process he promotes on his Website (www.mikewellsmastering.com) as “codec mastering.”

“Awareness seems to be coming around, where clients will ask me if I can provide them with a high-quality digital asset that's compatible in the marketplace,” says Wells. “I use the LAME encoder to create assets that are extremely compatible with players in the marketplace. There is also the free AAC codec, which is also very good for doing an AAC packet format. I use MP3 tag as my tagger application and then you're covering both bases so you have a nice digital asset format, fully tagged.”

Many digital distributors do not allow artists to submit encoded assets directly, and instead follow a batch-encoding process using submitted CDs. “iTunes used to allow you to submit your assets directly, but they stopped because it required too much QA,” Wells informs. “Apparently, they're making exceptions for the larger artists and charging a fee. But this is what I see as the independent artist's biggest bottleneck at the moment. They can come to me to get better-sounding digital assets, but then they run into problems getting it out into the marketplace.”

Wells notes that the M/S monitoring feature of his Dangerous Music transfer console has been particularly useful in mastering digital files. “I do a lot of work on the CD-mastering side in M/S, and I wondered whether I could deliver better results in the digital asset realm in M/S and I'm finding that I can,” Wells reports. “You do the encoding separately and then stitch the file back together, and it actually seems to sound much better. You can do dedicated encodings in M/S and reassemble your stereo from there.”