11/2/2010 3:53 AM
Having to master an MP3 is always problematic, but sometimes a sharp high-end cutoff, coupled with additional fixes to take care of other problems, can improve the sound.
I am not a professional mastering engineer,
but have become pretty good at it over the
years, and help my friends from time to time
by doing their mastering. However, sometimes
the only mix someone will have is an
MP3 version, and for whatever reason, they
can’t go back to the original tracks and do a
proper mix to WAV file. Sometimes they
even give me a 128kbps MP3, which of
course, would never be anyone’s first choice
I do the best I can but was wondering if
you know any techniques that can help
make better-sounding masters from MP3
Benjamin Mills, Lagos, Nigeria
EQ: We’ve noticed this disturbing trend as well,
where musicians convert directly to MP3
because they want to put their music on the
web, and either don’t keep—or don’t even create
in the first place—a high-resolution file without
Some MP3 files lend themselves to mastering
better than others. Often, if the person thought
that an MP3 would suffice as a master, then
there are other “rookie errors” in the recording
that mastering can’t fix. But sometimes an MP3
was created from a quality recording that got
lost over the years and is no longer available. In
that case there’s hope, especially if the MP3
was recorded at a higher bit rate.
Like any mastering, you need to consider
each piece of music on a case-by-case basis.
However, we’ve noticed that usually, the high
frequencies have an annoying quality that
“smells” of data compression. Often, applying a
sharp high-cut filter somewhere between 10
and 20kHz will make the high end sound much
sweeter. If this “dulls” the sound too much, a
slight boost below the range where you’ve cut—
for example, a dB or two at 5–8kHz or so—will
give a brighter, shinier sound.
Another problem with some MP3s seems to
be a muddy-sounding bass, although that can
be the result of the recording or mixing. Adding
a narrow peak and tuning it to the kick drum’s
fundamental can give more power in the low
end, and drive the song a bit more. Good luck!
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