Owners Manual

Which brings up the first thing last. The traditional way to have
loudness, dynamics, excitement and smoothness all at the same
time is with that old tool called 'arranging'. Take another listen to
your favorite records and check out how they use many instruments
to create loud or a few to create quiet or a relief. Listen to how solos
& intro instruments sound great when not covered by everything
else. If it happens to be a recording of great musicians playing
together, listen to how they are their own automatic level control.
This rarely happens with a mostly overdubbed song, but sometimes
a great mix simulates it. Dynamics galore, but a constant level,
hmmmmm.
OPTIMUM SETTINGS
Sorry, we can't really tell you where to set the knobs for female
vocals, a strat, or next year's standard mastering level. It all depends
on the track and taste and the sound you are trying to achieve. We
can give you a few guidelines and share some experience, if that
helps.
Limiting can be more audible or difficult than on a well set up
compressor given the same number of dBs of gain reduction. This
is because limiting has a higher ratio and typically has faster attacks
and releases. Old school engineers advise "to only limit a few dB on
occasional peaks", and this is good advice on most limiters. Hopefully,
you will be able to limit a little deeper with the SLAM! without the
usual problems. A limiter that shows, say, 5 dBs of reduction, can
sound louder than a compressor set for 1:1.5 ratio and dropping 10
dB almost steadily. Certainly during quiet passages, the compressor
will seem louder, but the limiter can seem louder in the hotter
passages when it is just grabbing transient peaks. The compressor
might be smoother and more tolerant of settings, but won't offer the
protection and 'drive' of a well set up limiter. The compressor's job
is to reduce the difference between soft and loud in a smooth even
way. The limiter's job is to inaudibly stomp on the hottest transients,
and prevent peaks from getting above a set threshold. It's all in the
names.
How can you tell when you have it set wrong and set right? There
is no 'wrong or right' that applies to every day, but we can suggest
the usual things an engineer listens for. You should experiment with
some drastic settings when you are alone or can without scaring a
client. There are 3 main things and the amount of reduction affects
each of them, so it is worth trying some heavy-handed settings to
imprint the symptoms to your audio memory.
The first is modulation distortion. When a limiter is set for dangerously
fast releases, the bass waveform gets into the sidechain, causing the
gain of everything to be changed on a low frequency cycle by cycle
basis. The result is a ratty sort of distortion, not really bright and
edgy like clipping, but usually not very pretty either, and often not
very useful creatively. With the SLAM!'s FET limiter, you can
easily set releases that are way too fast and cause modulation if there
are any significant lows in the signal. The cure is slower releases,
less limiting and/or slower attacks. Settings slower than 100mS are
generally pretty safe but always listen.
With the Opto, modulation can happen with about 10 dB or more
limiting on bass. You can use less limiting or try the side-chain filter
switch. Keep in mind that the side-chain filter will prevent some
limiting of loud low notes so there is a some risk of 'overs'. The
combination of both the Opto & FET can help share the load for
tougher signals like mixes and can be a sweet combination.
The second typical problem setting for limiters and maybe even
more for the SLAM! is pumping. The worst case scenario is a mix
that has a very hot transient followed by a significanty quieter few
seconds. A limiter should grab the peak, shove the gain down
sufficiently, then gradually return to normal gain. How gradually
depends on where you set the release. If the limiter was set so that
it reduced 20 dB, then that quiet passage may rise in level 20 dB over
a short time. This can sound pretty wierd depending on that quiet
passage. Unfortunately, some of the moderate release times, like
between 100mS and 500mS can be most obvious. Unfortunate
because, these are typically optimal settings for loudness
enhancement. Faster releases might distort and slower might tend to
hold the gain down or sit between peaks or beats. We have known
a few engineers to change release times on the fly, for transitions
between big chorusses and sparse verses that follow, and this can
work better than any electronic or algorithmic 'auto' setting.
The third problem is not really so bad unless you are attempting to
make the song loud. Releases set too long. When the release is very
long, a transient, however brief, triggers gain reduction, and a bar
later the gain is beginning to rise back to normal, and boom, another
transient reduces the level again. You could have turned down a
fader or final gain control and gotten the same effect. The SLAM!
isn't immune to this, but the slowest release is moderate at 2 seconds.
Some limiters have much longer releases. 8 second releases tend to
be safe and almost inaudible, but pulling a fader down a few dB
before the song starts is very, very inaudible and does about the same
thing. Sometimes the best thing, is to ride the fader, slowly, gently,
then add the limiter for what it does best - extremely fast reaction.
Vocals can be a prime candidate for limiting. Perhaps the most used
limiter ever for pop vocals is the vintage LA2A. The ELOP Limiter
in the SLAM! recreates that action, and goes a few steps further with
side-chain filters and FET limiter. Start with the ELOP typically on
the 100 SC filter (or 200 if esses need a bit of extra taming), get the
INPUT & ELOP LIMITER levels optimum, adjust for an optimum
level to 'tape'. Then maybe sneak in a bit of FET Limiting, with
Attack at VF, RELEASE between 1 sec and 100 mS.
For a Mix, we generally lean on the FET Limiter for most of the work.
Releases again between 1 sec and .1s are OK, but .1s is verging on
dangerous. Attack will be important. VF attacks will sound cleanest
but less punchy. Adjust to taste and watch out for loss of drums at
VF and distortion at M. Adding some ELOP will be subtle if more
than 6 dB of FET limiting is used. We suggest using the 200 SC filter
to tame highs and de-ess sometimes.
Guitars may like the FET CLIP setting for a bit of extra crunch. Bass
may require slow releases, and VF attacks for ultra clean sounds, but
for extra growl, there are quite a few settings that go there. Faster
releases, deeper limiting, and slower attacks each contribute to
various distortions, not to mention just overdriving levels. Piano is
difficult usually, but try faster attacks, slower releases and not too
much limiting.
Drums - well, you just gotta play with the SLAM! to find the most
appropriate sound. You can certainly tame dynamics, exagerate
room sound, crunch and mangle. Faster release times bring out the
room sound and ambiance. It's a bit drastic, but you can use one side
of the SLAM! for mic-pre and limiting, go out to an EQ, and return
to the other channel for yet more limiting, drive and A/D conversion.
You might record that first channel as a minimally processed back-
up too. Save something for the mix.
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