Some helpful information to help resolve Test Pressing questions and issues.
Mastering
Dance and Hip-Hop
Records
Records
intended for club play are normally cut at a higher volume than regular
12" LP records. It is important to realize that club records are cut
hotter than vinyl records were ever intended to be cut.
They are "pushing the envelope" of acceptable distortion
levels. It is only possible
to cut at "club levels" if the sides are kept to 12 minutes or
so per side. If sides are
longer, the cutting level has to be lower to fit the side on the record.
In order to cut at higher volume without unacceptable distortion
and skipping, a few factors must be taken into consideration.
The
first factor is vocal sibilance, 'S' sounds.
This is caused by excessive 'S' levels creating curvature of the
recorded groove which is smaller than the radius of the stylus which will
play it back. 'S' "break-up" or distortion, is one of the
biggest problems in playback. Steps
must be taken in cutting to prevent this.
A fast acting treble limiter is used to keep the 'S' sounds in
check. The amount used is the
amount needed to keep cutter current to a known acceptable level.
If vocal tracks can be "de-essed" in recording and
mixing, much less treble limiting is necessary in cutting.
The
other big problem is low frequency bass sounds which cause the playback
stylus to skip out of the groove. Since
hip-hop has so much low bass, it is not uncommon for information below
20Hz to be recorded. Excessive
boost below 40Hz will bring up the area below 20Hz to unacceptable levels.
This is also sometimes caused by "scratching effects"
where the record is slowed way down and the playback stylus pushed back
and forth. It is actually
possible to produce frequencies almost down to DC this way! Since the resonance of most arm/cartridge combinations is
around 10 Hz, any loud information near this frequency can easily throw
the playback stylus out of the groove.
Have you ever played a hip-hop record and watched the whole arm
wiggle on bass peaks? That
indicates bass energy near the arm resonance.
For these reasons it is necessary to filter frequencies below 30 Hz
to keep this subsonic information out of the groove.
The
last problem is excessive stereo effects or out of phase information at
bass frequencies. These can
cause overly deep grooves that waste space on the disk and are very hard
to fill on the pressing. This
leads to decreased time or level, and increased distortion and noise.
It is better to keep things panned in from the sides. It doesn't have to be mono, but is better if not TOO stereo.
These
three areas are the biggest problems.
If steps are taken to reduce these three problems when recording
and mixing, the pressings will sound much more like the DAT or CDR.