Empirical Labs EL-Rx - Manual (Page 6)

Example Settings 2
Guitar Settings (cont’d)
On guitar, the studio quality compressor in the DocDerr can be used in a number of ways. It is
an extremely fast compressor, helping to tame pointy transients, while bringing up the sustain on
each and every note. One can control the amount of compression with the volume control on his
instrument. There are at least three different ways to use this limiter/compressor, on a guitar:
1) As a gentle peak tamer, using 100% Mix (mix on 10), averaging 3 – 6 dB of gain reduction,
but putting on 10 – 12 B of compression on the loudest percussive passages. The speed
and smooth knee will make this almost inaudible as actual “compression”.
2) As a smasher, crushing strumming parts to make it fit into an ensemble at a nearly
constant level, and bringing up solo lines so every note is heard. 12 to 20dB of
compression on peaks is quite usable here. 100% Mix.
3) As a natural sustainer, using the MIX control to enhance the uncompressed DRY level,
letting the compressed signal fill in the sustains, long after the main attack is gone. The
peaks will still come thru but low level notes and sustains will be more present. You can
use lots of compression here if you want (12 – 20dB), keeping the compressed level quite
a bit lower than the peak levels, and still sound quite natural.
The basic tone and character of your guitar can be greatly enhanced with this studio quality
Empirical Labs compressor, giving you a “finished” sound.
Clean Electric guitar
One can get great, clean electric guitar tones plugging into the DocDerr alone. Going in direct,
you will need the input jumper set to INSTRUMENT IN. Otherwise, you will probably use a mic and
preamp, setting the DocDerr for Line In. Again if this is a solo guitar, you can leave much of the low
frequencies in, perhaps just using the 70Hz High pass. The tone is in the 160 – 500 Hz range but as
noted, that is also a range that can make the guitar sound muffly, so treating these frequencies
properly is very important. If a guitar sounds thin and lifeless, sometimes boosting a little in that
range and pulling out 4k – 12K will make it fuller and more pleasing. A guitar amp has very little
above 10K, and an excess of these frequencies will make a guitar sound “tinkly” and unnatural.
The compressor is your greatest tool for getting album quality clean electric guitars. Harsh
plucked transients are often 20dB above the body of the sustain, and with its fast attack, the DocDerr
compressor can even these out, and bring up all the body of the strings. When in an ensemble,
100% mix (Mix on 10) can work wonderfully to help the guitar take up a nice space, without jumping
out. 6 – 12 dB will sound very natural, while even more compression can be quite tasteful when
playing with other instruments. When used on a solo instrument, one may want to use the Mix
control to keep the compression from being too obvious. Mixed in behind the dry, a very
compressed signal can sound like it has been run through a tube amp. The harmonics will add
crunch and sound less sterile, while the sustain will be dramatically enhanced.
Crunchy Distorted Guitars
You will usually need a microphone and mic preamp when using a real amplifier. However,
software tube amp emulators have come a long way. The DocDerr will then probably be used in
LINE IN mode (See Jumper Settings), since it will probably have too much gain for a mic pre or
workstation preceding it. Because distortion adds an incredible range of harmonics, and because of
the interaction between a guitar, amp, speaker and mic, really drastic frequency spikes and
resonances are common on guitar tracks. They can make or break the track… and they can also
make EQing very tricky. So spend time getting a great basic tone without processing.
Muffly guitars are a common problem. Adding 3 – 8KHz can bring out the “STING” and clarity.
Too much though, and you end up with a buzzy tone. Conversely, another method to get rid of the
“muffles” is to pull frequencies from 150 to 500Hz. Often there are frequencies below 80 – 140Hz
that just turn into mud in a mix. Here, the 100Hz high pass filter can do wonders. Soloing guitars in
mixes can be dangerous, especially with the guitarist present! If for instance, you use the 100Hz
High pass on the guitar while soloing, the fullness will be thinned out somewhat, and the guitarist
isn’t going to want that… but the “Mix” might! The warm tones are the same as the muffly area, 160
– 500, and sometimes it helps to add AND subtract adjacent frequencies in that range. Sometimes
a midrange boost in the 500 to 2KHz range can help a guitar fill out without getting brighter. Again,
there are no rules except what your ears tell you while listening in the mix.
Band limiting guitars is an extremely useful technique, not only on the low end as above, but on
the high end also. Try rolling off 5 – 12KHz on electric guitars and often, they will sound tighter,
quieter, and often warmer. Set the high PEQ band to 10KHz and pull it down 4 – 6dB and see if the
guitar gets warmer and tighter sounding. Often there’s just pick noise and hiss up there.
5
Block Diagram
1
3
2
2
3
1
Balanced In
Compressor
HP
Filter
Output Amp
Unbal
Dig Control
LF PEQ
Circuit
Saturation
Mix
Balanced Out
(Tip)
MID PEQ
Dig Control
Dig Control
HI PEQ
Input
(Drive)
Input
Amp
Dry
Compressed
(I/O Connectors Not On Module)
HF
Section Details
The Input & Output
The input has two modes of operation, Instrument In, and Line In. There is a 3 pin Jumper that
selects this, and is set to Line In Mode from the factory (see Jumper Settings on p3). The “Line In”
jumper setting changes the DocDerr into an electronically balanced line receiver circuit. It is
relatively insensitive to all kinds of wiring, be it balanced or unbalanced. If using an unbalanced
signal however, it is preferable that the unused pin 3 is grounded, or at least not left unconnected.
Pin 2 is “Hot” and complies with the AES standard. In Instrument Mode (jumper towards rear), a
mono guitar cable shorts out XLR pin 3 (Phone ring), and produces 16dB of very clean gain. 16dB
was selected as a safe gain that will not clip, but produce a line level signal out of most instruments.
The output section has the option to be single ended, or differential output. The select jumper
is set to differential mode from the factory (see Jumper Settings on p3). When in Dif Out mode, the
jumper produces differential out, applying an inverted signal to XLR pin 3. The gain is 6dB louder
over single ended mode. However, if there is a chance of clipping an amplifier, mixer, or whatever,
the single ended mode will be a safer way to go. The single ended mode has the other advantage of
not being sensitive to any wiring issues, since one cannot accidently short pin 3 to ground, causing
an amplifier to “dump” current into it. However, when recording straight into a recorder or
workstation, it may be better to keep the jumper in differential mode and get a hotter output signal.
The EQ Sections
There are 4 sections of EQ in the DocDerr. One selectable High pass filter, and 3 sections of
parametric EQ.
The High pass is 18dB per octave (3rd order) and has two selectable frequencies, 70Hz and
100Hz. The High Pass frequencies are selected by pressing the LF and MF parametric switches at
the same time (simultaneously). This is noted on the front panel. The 70Hz is largely to cut subs
from the instrument caused by “instrument body resonances” and pick or hand noise against the
instrument. It will leave the fundamental frequencies of a guitar alone. The 100Hz filter cuts out
more of th e sub frequencies, often making a more realistic guitar response. It also prevents some of
the low frequencies from getting in the way of other instruments in an ensemble (band).
10
Example Settings 4
Percussion
Drums and percussion are sources that often need liberal amounts of processing. We will touch
briefly on a few tricks for common percussion issues.
Kick Drum EQ – Woofy kick drums can often be fixed with lots of 220 – 400Hz pulled out. It is not
uncommon to get a great sound just pulling 6 – 12 dB of 300 – 400 Hz out. Set the LF parametric
EQ for –9dB at 400Hz to start. The level will drop dramatically with this EQ since there’s usually
tons of power in this frequency range, but usually, the overall tone will be much better. To add
attack, add 5Khz – 8Khz with one of the upper two PEQ (parametric EQ) bands. Check your kick
drum on several speakers!
Snare – Snares often need some top and bottom. This again hints at possibly pulling a generous
amount of a mid frequency to bring the low and high frequencies out. Try pulling frequencies
between 350 – 1.5KHz. This often sounds very natural but again, always EQ drums in the mix with
the other drum mics on. Soloing while EQing is dangerous, especially on drums where many mics
can interact with each other. If you still need some snap and sizzle in the high frequencies, try +5 @
8KHz. Watch out for high hat and cymbal bleed since this is a common problem. Adding thud and
body to the snare is usually done in the 100 – 200Hz range. Try +2dB @ 150Hz (100 – 200) and
tune from there. High passing the snare at 70 or 100Hz can often clean up the low end and help the
kick drum due to phase problems. Analog tape was always a big help in getting a fat, punchy,
natural snare. If the snare has a plastic edge and needs sustain, experiment with the
compressor/saturator. In mixdown, the DocDerr compressor can bring smack and sustain.
However, we urge you to record the drums without compression, or at least keep a copy of the
uncompressed track on tape (DAW). Compressing while tracking will increase bleed and possibly
make it tricky to gate or trigger samples later on. Room or ambient mics are a possible exception.
Percussion such as tambourines, congos, etc can often be treated with some compression while
recording without much risk.
Mixes & Buss EQing
- For those who aren't used to the jargon... A “BUSS” is usually a pair of
channels (2) that have pre mixed instruments or stereo music on them. The Left & Right outputs of
your CD (music) player could be considered a 2 channel buss. In the recording studio, it is more
often applied to the final left and right channel mix, or to something such as all the drums mixed
down to 2 tracks (a "submix"). Now, instead of riding or processing 12 channels at once to move the
drums up and down, you only have to work with two.
A common problem with mixes or submixes is overall “dullness” or lack of high end clarity. Use
the high band centered at 10 – 15KHz. Alternately, cutting some lows or low mids can clarify a mix.
The 250 – 600Hz range is a common target. Pulling out frequencies between 250 – 600Hz can often
clear up a whole mix, making the low end and high end come out in a pleasing way. If there are
vocals present, watch out for losing their pleasant warmth and body. Often mid frequencies will pile
up between 1 – 5Khz. Our ears are most sensitive to this range and one can often pull 1 – 3 dB with
a parametric band (-1.5@4K) after high frequencies have been boosted. Mastering mixes is almost
always an art of compromise.
The compressor can be extremely useful for adding excitement to mixes or busses. Because
the compressor is so fast, you will either use the DocDerr compressor as a peak limiter (1-3dB), or
use the mix control to add in a little compressed signal to the dry signal, bringing up details and
sustain, helping fit the mix together and sound more finished. When using the MIX, you can
sometimes apply 6 – 10dB (or more) of compression blended under the dry signal. Don’t forget you
can disable the compressor and just use the tape-like saturation, which helps integrate frequencies,
filling in cracks and increasing the apparent volume.
LIVE SOUND REINFORCEMENT
– The DocDerr is expected to find prolific use in
sound reinforcement systems for many reasons. The unit is built like military gear, extremely strong
with many connections doubled up, making it extremely road worthy. The lettering is quite large
compared to many mixer eqs, making it easy to read in dim light, and the knobs are carefully
calibrated for repeatable settings. And of course, the extreme versatility and multitude of tonal
processors contained within it, should allow the sound engineers to handle most any problem he
encounters in his day to day life on the road.
Direct box – The high performance preamp in the DocDerr was meant to be used as a stage
preamp. Since its performance exceeds most instruments output signal to noise, guitar, bass,
synths, and drum machines will all come out clean and fat, with the DocDerr adding little noise.
9
Example Settings 3
Sometimes the guitar just needs a touch of fatness without losing attack, don’t forget that
cutting a high mid (1- 4KHz) can sometimes take out a nasty honk and let the body in the lower
frequencies pop out. Crunchy guitars, which are full of harmonics, are notoriously sensitive to tonal
changes. You can often notice a 1 dB boost or cut on an electric guitar much easier than you could
on a vocal, drum or other instrument. Analog tape was always a big help with vocals and electric
guitars because it clipped all the pointy peaks and saturated when the high frequencies piled up.
One can try just the saturator in the DocDerr by disabling the compressor (press LF and HF).
Bass
– Bass is a difficult instrument to get “right in the mix”. The DocDerr has many ways to help
round out and make it cut through in a mix. First, if a low bass tone is too pure and sine-wave-like, it
will "fall off" on small speakers. By this we mean it will not be audible because most of the bass
frequencies are below the range of the speakers.
Try bringing out 700 to 2KHz with a mid PEQ Band. These will accentuate the upper harmonics
that will reproduce on small speakers. Sometimes pulling out frequencies around 300Hz will bring
out the low end and high end on a bass and give that frequency range more room in a mix for the
guitars vocals, etc. But pulling out too much 200 – 400Hz can give you a hollow sound that has no
warmth on small speakers. Also, the DocDerr compressor can add “tubey” harmonics to cut on
small speakers. The more compression the more harmonics. Use the Mix control to tame the
compressor. The compressor will tame the clacky attacks and lengthen the sustain.
It is not uncommon in this digital age to have too many sub frequencies on a bass track. Try
the 70Hz High pass, you will be able to raise the bass level in a mix, giving it clarity and leaving the
sub freqs to the bass drum. Boosting low freqs on an EQ before a compressor lets the compressor
grab the eq points and control them. Often accentuating around 100Hz will give the bass plenty of
bottom. Conversely, if you are boosting EQ after the compressor, those new frequencies will be
there to stay. An EQ following the DocDerr’s EQ and Compression will give any engineer enough
tools to get a great sound no matter what he started with.
Sometimes there aren’t a lot of important frequencies on the bass above 4KHz, Try pulling out
a wide band at 4 KHz or above to cut clack, hiss, excessive pick noise etc. I have seen engineers
“band limit” the top and bottom end of the bass to approximately 60Hz through 4 KHz, letting the rest
of the tracks fill in above and below this band.
Vocals
– It’s most important to pick the right mic, the right distance and the right angle for the
singer. The most expensive mic isn’t always the best mic for a person’s voice. Also, sometimes the
mic that needs the least EQ isn’t the best mic either. And moving a person a couple inches in and
out from the mic can make all the difference in the world.
EQing - Don’t overly brighten! Of course, a certain amount of high boost is frequently required.
But, often harsh sibilant frequencies suddenly pop out making a perfectly good vocal become this
scratchy, hissy annoying squawk. Try setting up the compressor first, while adjusting the EQ, as it
keeps level changes from fooling you. Pulling some woofy or pointy lower mids can bring out the
body and high frequencies without exaggerating the spit, S’es, and high frequency resonances in a
voice. There is a danger in removing the body in the 150 – 300 range so keep your ears alert when
working these frequencies. A dB or two may be enough. Try pulling freqs from 2K to 4kHz out to
smooth and bring out the low and top end, and get rid of harsh “honk”.
The DocDerr compressor is magic on vocals, and brings a great modern sound to them. It
brings the body up but will also bring out the honk, breaths and sibilants (sibilants are the annoying
S’es, T’s K’s that have a high frequency transient nature). Try our DerrEsser to tame these artifacts.
Keyboards
– Obviously in this sampled age, this covers a lot of sounds, and Acoustic Pianos
are a whole subject unto themselves. We can give some quick generalizations here. First, don’t
forget to properly set the Instrument In jumper. If the level of the keyboard is low, set to instrument
in. However, modern synths can usually work fine at LINE In levels. Either way, the DocDerr makes
a great DI box. Treatment depends on the final setting, I.E. Solo keyboards, or as part of a larger
ensemble. Getting a big full sound is usually the goal of solo keyboards pieces, unlike ensemble
playing. In ensemble playing, high passing is often useful, especially if there are potential conflicts in
the low end between the synth and bass parts. In the latter case, the DocDerr high pass will prove
invaluable for removing the mud that can occur from a left hand/bass conflict. Try 100Hz High Pass
setting here. Synths often have “plucky” top ends. One can band limit the top end up there, or try the
Compressor/Saturator to control the peaks. Sometimes string sounds have a midrange grit to them
and using a PEQ (Parametric Equalizer), one can pull out 800 – 4KHz (start at 2KHz) and get a
silkier sound that sits in the back and lets the guitars and vocals have that upper midrange area.
Rolling off top end can help get rid of the buzz of a synth part. Cutting freqs on one track, gives room
for them elsewhere. 6
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