What is An Accurate Tone Balance

Perhaps the prime reason clients come to us is to verify and obtain an accurate tonal balance. The output of the major mastering studios is remarkably consistent, pointing to very accurate studio monitoring. As I've pointed out, the goals of equalization in mastering are generally different from equalization in mixing. It is possible to help certain instruments (particularly the bass, bass drum and cymbals), but most of the time the goals are to produce a good spectral balance. What is a "good" tonal balance? The ear fancies the tonality of a symphony orchestra. On a 1/3 octave analyzer, the symphony always shows a gradual high frequency roll-off, as will most good pop music masters.
Everything starts with the midrange. If the mid-frequency range is lacking in a rock recording, it's just like leaving the violas or the woodwinds out of the symphony. The fundamentals of the vocal, guitar, piano and other instruments must be correct, or nothing else can be made right.

Specialized Music Genres

It's one thing to understand the symphony, and another to properly balance all the different music genres. The bass plays very different roles in each popular music genre. You could think of Reggae as a symphony with lots more bass instruments, but let's not get too hung up on the symphony analogy. Just remember to keep the symphony balance in your head as a basic reference, especially in the mid to high frequency balance.

EQ Tricks

Remember the yin and the yang: Contrasting ranges have an interactive effect. For example, a slight dip in the lower midrange (~250 Hz) can have a similar effect as a boost in the presence range (~5 kHz). Harshness in the upper midrange/lower highs can be combatted in several ways. For example, a harsh-sounding trumpet-section can be improved by dipping around 6-8 kHz, and/or by boosting circa 250 Hz. Either way produces a warmer presentation. The next trick is to restore the sense of air which can be lost by even a 1/2 dB cut at 7 kHz, and this can often be accomplished by raising the 15 to 20 kHz range, often only 1/4 dB can do the trick. Remember the interactivity of the frequency ranges; if you make a change in any of them, you must reevaluate your choices on them all..

When you go to concerts, do you sometimes think you hear edits.

High Q or low?

Gentle equalizer slopes almost always sound more natural than sharp. Q's of 0.6 to 0.8 are therefore very popular. Use the higher (sharper) Q's (greater than 2) when you need to be surgical, such as dealing with narrow-band bass resonances or high-frequency noises. The classic technique for finding a resonance is to start with a large boost (instead of a cut ) to exaggerate the unwanted resonance, and fairly wide Q, then sweep through the frequencies until the resonance is most exagerated, then narrow the Q to be surgical, and finally, dip the EQ the amount desired.

Equalizer types

Most of you are familiar with the difference between parametric and shelving equalizers. Parametric is the most popular equalizer type in recording and mixing, because were we're working with individuell instruments. In mastering, shelving equalizers take on an increased role, because we're dealing with overall program material. But the parametric is still most popular as it is surgical with defects, such as bass instruments that have resonances. Very few people know of a third and important curve that's extremely useful in matering: the Baxandall curve (see ill). Hi-Fi tone controls are usually modeled around the Baxandall curve. Like shelving equalizers, a Baxandall curve is applied to low or high frequency boost/cuts. With a boost, instead of reaching a plateau (shelf), the Baxandall continues to rise. Think of the spread wings of a butterfly, but with a gentle curve applied. You can simulate a Baxandall high frequency boost by placing a parametric equalizer (Q=approximately 1) at the high-frequency limit (approximately 20 kHz). The portion of the bell curve above 20 k is ignored, and the result is a gradual rise starting at about 10 k and reaching its extreme at 20 k. This shape often corresponds better to the ear's desires than any standard shelf.

Most times the same EQ adjustment in both channels is best, as it maintains the stereo balance and relative phase between channels. But sometimes it is essential to be able to alter only one channel's EQ. With a too-bright high-hat on the right side, a good sounding vocal in the middle and proper crash cymbal on the left, the best solution is to work on the right channel's high frequencies. The Finalizer does not currently operate on seperate channels, but other TC products provide this flexibility.

If the piano solo is weak, we try to make the changes surgically:
- only during the solo.
- only on the channel where the piano is primarily located, if that sounds less obstrusive.
- only in the fundamental frequencies if possible.
- as a last resort by raising the entire level, because a keen ear may notice a change when the gain is brought up.

Instant A/B's?

With good monitoring, equalization changes of less than 1/2 dB are audible, so subtlety counts. You probably won't hear these changes in an instant A/B comparison, but you will notice them over time. I will take an equalizer in and out to confirm initial settings, but I never make instant EQ judgements. Music is so fluid from moment to moment that changes in the music will be confused with EQ changes. I usually play a passage for a resonable time with setting "A" (sometimes 30 secons, sometimes several minutes), then play it agein with setting "B". Or, play a continuous passage, listening to "A" for a resonable time before switching to "B". For examble, over time it will become clear wether a subtle high frequency boost is helping or hurting the music.

Equalization or Multiband Compression?

Many people have complained that digital recording is harsh and bright. This is partly accurate: low-resolution recording (e.g., 16 bit)) doesn't sound as warm to the ear as high-resolution. In addition, digital recording is extremely unforgiving; distortion in preamplifiers, A/Ds errors in mike placement are mercilessly revealed. The mastering engineer recognizes these defects and struggles to make a pleasant-sounding result. Use equalization when instruments at all levels need alteration, or one of the best tools to deal with these problems -multiband compression, wich provides spectral balancing at different levels. It is possible to simulate the often-desirable high-frequency saturation charakteristics of analog tape with a gentle high-frequency compressor. Use increased high-frequency compression at high levels when the sound get harsh or bright. Or, vice versa, if you find that at low levels, the sound is losing its definition (wich can happen due to poor microphone techniques, noise in the recording, or low-resolution recording) ... then apply gentle high frequency upward compression, engaged at lower levels. This function, often called AGC, is not available in the Finalizer, but can be found in the DBMAX by TC Electronic.

EQ Interaction with the compressor

If you're using split dynamics, make your first pass at equalization with the outputs (makeup gains) of the three bands. 3-band compression and equalization work hand-in-hand. If you're splitting dynamics processing, then tonal balance will be affected by the crossover frequencies, the amount of compression, and the makeup gain of each band. Before engaging an equalizer, first try to correct overall tonal balance with the makeup (output) gains of each compressor band.

Quelle: Bob Katz