Audiobook mastering is a fine art, ensuring good technical quality whilst allowing the narrator’s voice to enjoy a full dynamic range. Too often this part of the production process can cause problems, with audio being overly compressed/limited, too much gain added and distortion and other processing artifacts creeping in. So, here’s a brief, handy guide to how to get the best out of your mastering stage. It’s what we do every day for our clients, and our own audiobook titles. Remember…We Love Audio!
Here’s how NOT to master an # chapter. Notice the over use of gain leading to an aggresive dynamic range and a lot of transient peak distortion:
Whilst not overly compressed or limited, the excessive use of gain when mastering has caused the peaks to go way beyond 0dB. Adding a limiter to this output process (e.g. -3dB) the end result ends up as this…squashed, distorted and muddy:
Audiobooks need subtlety when mastering. Dynamic range and subtle EQ and limiter/compressor useage. Also, -3dB is a peak max, not an average.
So, here we have taken that first file and put it through extensive restoration, de-peaking and tidying:
As you can see we have a much nicer looking AND sounding wave form. The editor should have de-peaked a bit more as they edited the file, but overall it is healthy and sounding much nicer. The distortion is gone and the overall sound is less tiring on the ears.
From this point, we can apply soft mastering processes. A slight EQ to remove some low end, plus a tiny bit of high end for brightness (these will change depending on the source recording, the studio/mic sound and the tonal quality of the narrator). After that we apply some soft compression and a maximiser (if required) with a -3dB limiter. THEN we experiment, bouncing down the file and checking the mix to ensure good quality throughout…no distortion or compression sounds, engaging but not noticeable EQ, etc…
Once the files look/sound good, we go ahead and master the files, checking each as we go. Here’s the same file, now correctly mastered:
As you can see we have good range up to the peak -3dB allowing for an engaging narration WITHOUT compression artifacts or distortion. NB in this instance we have mastered to the max level required by Audible UK, but you will need to adjust this to fit your or your client’s requirements.
 subtlety in use of gain/EQ/compression/limiting
 less is more, allow for dynamic range
 Monitor the file after EVERY process…check your files
 Use your EYES and your EARS
 Use gain increase BEFORE editing not after
And that’s it folks. Hope it was useful. We are here to help with any of your # needs – from advice to production. Just drop us a line anytime.