Mastering with Sound Forge (Part 2)
by Craig Anderton
Last issue we covered mastering basics. Now, let's use the Sound Forge Mastering EQ feature (under DirectX plug-ins) to fix frequency response problems. For this tutorial I am using the newly-released Sound Forge 9 software.
Some fixes are "broad strokes," like increasing or trimming the treble range or bass range somewhat. These are fairly easy to do: Compare what you're mastering with a well-mastered recording, and adjust the high and low ends for the same subjective sound.
Peskier problems involve finding unpleasant frequency response peaks or dips, for example from material recorded in a room with bad acoustics. These can make the audio sound "peaky" or "hollow." The object is to identify where these problems reside, then fix them. To deal with peaks:
- Open the mastering EQ, and turn off all bands except Band 1.
- Turn down your monitor speakers (important)!
- Adjust the band's gain (dB) control to 15dB by either clicking and dragging up on the band's dB numerical field or dragging the graphic "ball" upward.
- Set a fairly narrow Q (width), like 5.00, by clicking and dragging on the Q/Slope numerical or clicking on the < or > symbol surrounding the "ball" and dragging left or right (the mouse scroll wheel works for most of these edits too).
- Turn up the monitors a bit. The sound will be much louder than normal because of the 15dB boost.
- Sweep the filter peak's frequency up and down, slowly, by clicking and dragging on the Hz numerical for band 1. You could also drag the ball, but this might change the gain and you want a constant gain.
- When you hit a resonance, the sound will get ultra-loud and distorted. This identifies a peak in the sound. If everything sounds distorted, reduce the gain a bit and try again.
Now that you've found a peak, decide whether it's a natural peak that's supposed to be there, or a "bad" peak. Reduce the dB gain to a level below 0 (e.g., -3), then decide whether the track sounds better or worse. If better, optimize the gain and Q while comparing the original/edited sound by clicking on the check box to the left of Band 1.
For example, I once mastered a track that was mixed on a system with poor bass response. As a result the kick drum was mixed too high, giving a muddy sound. I isolated the main kick frequency (around 65Hz) and cut 1.2dB, with a fairly narrow width, to bring it into the correct sonic balance. On another project, a frequency build-up around 400Hz caused by bad arranging was fixed using 0.9dB of cut, with a fairly broad Q, to make the sound less "tubby" (Fig. 1).
Fixing dips is more difficult. After taming any peaks (which may require multiple bands), I usually just create a broad boost of 2dB or so, and sweep over the frequency range. If there's a noticeable improvement in one part of the spectrum, I'll work with the Q, gain, and frequency to tame the dip.
Finally, mastering involves subtlety - a difference of even 0.5dB can have a major effect on the sound. If you're starting out, try making the desired gain change, then cut it in half (e.g., if 2dB sounds right, change that to 1dB). Live with the track for a while, and see if the lesser value works for you.