Manley HIGH FREQUENCY (DE-ESS) LIMITER - Manual (Page 5)

David designed this unit to be used on the most critical tracks and mixes where the maximum
degree of fidelity is needed. The success of a song often depends on the vocals and production. Excessive
sibilance on vocals (and mixes) is a very common problem and can be caused by several factors. We
believe that the best solution is to not create the problem in the first place. The HIGH FREQUENCY
LIMITER is designed for engineers needing to correct problems. The next section deals with methods
to avoid sibilance problems before the fact.
The hardest problem to deal with is a vocalist with a natural sibilance problem. This is often
caused by a gap in the front teeth creating a "whistle". The best cure is usually to fix the source. If the
singer can not control the problem perhaps a bit of cotton in the "gap" if they can tolerate it. One might
think notching the offending frequency would help but usually the whistle is a pretty wide band and a
notch that wide will dull the entire vocal. The HIGH FREQUENCY LIMITER will probably be a better
tool than EQ in this situation. One must be very careful during recording not to use too much deessing
because correcting that in the mix can be more difficult.
Most engineers believe the worst source of sibilance problems is the common practice of
boosting highs on vocals. Wrong. The most common cause of bad sibilance is bad equipment. The EQ
usually just exagerates the problem. With the right gear - no problem. The technical name for this type
of sound is Transient Intermodulation Distortion (TIM). Cheap IC Opamps are the most common
offender but we are aware of many tube and discrete mics and mic preamps with this curse. Our
guaranteed solution is to use our REFERENCE GOLD or CARDIOID MICS with our MIC PREAMPS.
This is not a cheap plug, it is the best solution that we know of. Considering the expense of your studio,
it is really a relatively low cost answer to provide magnificent recordings without problems. Not only
will your tracks sound awesome, it is very likely less EQ will be called for and no nasties if EQ is needed.
You still need to be careful to avoid other dangers in the recording chain. Beware of cheap solid state
compressors and gates, some console EQs, some digital recorders , etc. The good stuff won't add that
harsh, ugly, sibilant distortion. The good news is that it is actually easy to mic, EQ, compress, record,
boost highs again, compress again, mix and master without a hint of sibilance problems providing one
uses good equipment and some awareness. The bad news is that too often a studio has no great choice
in gear or the engineer has to fix some other person's recording.
The other sources of harsh top end are better recognised. Of course "over EQ" can do it. So can
most forms of overload and clipping. The combination of EQ and clipping and cheap IC based gear is
almost guaranteed to get you renting or buying de-essers. As to clipping - A good way to think of
sibilance is like cymbals, hi-hats or some percussion because of similar high frequency transients. These
instruments record best at a lower VU level. VU meters do not really read the fast transients nor do they
show the analog tape EQ curves. If the highs are already distorted by less than wonderful equipment then
naturally boosting the highs will boost that distortion with it. If the highs are clean and the top is boosted
then the big variable is the quality of the EQ. Watch out for equalizers that are harsh rather than airy.
While you probably have most control over how much to push the highs and at what frequency and Q
remember to listen to the side effects of these changes. Remember that the mastering process is a good
choice for boosting the highs, in general, on a mix. This way you don't have to "stretch" the limited range
of the console EQ, and the monitors in mastering may be better suited for that final touch. Besides it is
likely the mastering EQ will be better equipment than the studio has.
PREVENTING SIBILANCE PROBLEMS