Daking Audio Comp IIT User manual
Safety Considerations
• Read, follow and keep these instructions.
• Heed all warnings. Install in accordance with the manufacturer’s instructions.
• Protect device from liquids and spills.
• Clean only with a soft, dry cloth
• Do not block any ventilation openings.
• Do not install near any heat sources such as radiators, heat registers, stoves
or other devices (including amplifiers) that produce heat.
• Do not defeat the safety purpose of the grounding-type plug. A grounding-type
plug has two blades and a third grounding prong. The third prong is provided for
your safety. If the provided plug does not fit into your outlet, consult an
electrician for replacement of the obsolete outlet.
• Protect the power cord and all connecting cables from being walked on or
pinched, particularly at plugs, receptacles, and the point where they exit from
the device.
• Only use attachments or accessories specified by the manufacturer.
• Unplug this device when unused for long periods of time.
• Refer all servicing to qualified service personnel. There are no user-
serviceable parts inside. Servicing is required when the apparatus has been
damaged, such as when a power-supply cord or plug is damaged, objects have
fallen into the apparatus, the apparatus has been exposed to moisture, does not
operate normally, or has been dropped.
• Do not overload wall outlets and extension cords as this can result in a risk of
fire or electric shock.
1.0 About Daking Audio
Congratulations! You’ve purchased a Comp IIT, a very high-end piece of gear!
The Comp IIT uses discrete transistor Class A circuits, VCAs, Jensen input and
output transformers and printed circuit board-mounted switches. Signal
capacitors are precision polypropylene or ultra low-leakage electrolytic types.
Our boards are assembled on a mil-spec assembly line. The chassis are
stainless steel for maximum RF and hum rejection and a long-lasting finish.
Every unit is hand-finished, tested, burned in, and tested again in a second
facility.
Also, we just couldn’t stand to use plastic knobs, so we designed our own
anodized, engraved aluminum knobs that give a much more precise and quality
feel. We designed our gear to be gear you’ll own for life, not some passing
fancy you’ll leave in the dust once you figure out what the good stuff sounds
like. This IS the good stuff.
-Geoff Daking
1.1 In The Box
•Daking Audio Comp IIT 19” rack-mount single-space Compressor-Limiter
•Outboard power supply with attached connecting cable
•Power cable
•.050” hex wrench for knob set screws
1.2 What Is a Compressor-Limiter?
A compressor is a device that helps control the dynamic range of a track
you’re recording or mixing. Example: if you’re recording a vocal and the singer
is going from very soft to very loud, a compressor can make the loud parts not
quite as loud. Then you can turn up the overall level of the vocal to hear the soft
parts better. As a result your vocal will have a more consistent level in your mix,
while still retaining its expressiveness. Compressors are also frequently used on
guitars, bass, piano, and other instruments for the same reason - to record a
consistent level that will hold its place better in your mix. Used sparingly a
compressor is transparent - the listener can’t hear it working. Used poorly it can
suck all the life out of whatever you’re recording, and that can’t be undone by
any amount of later processing. Some people will use compression aggressively
as an effect, and that’s perfectly valid if it’s what you want. Always listen and
keep an eye on the gain reduction meter. Try aiming for -3dB to -5dB of
compression as a starting place when recording a vocal. Remember: you can
add more compression later, but you can’t take it away.
When mixing many engineers use a stereo compressor to run the entire
mix through. It can make your mix more aggressive and more alive sounding,
more integrated. “Glue” is a term many engineers use for mix compression.
Again, too much compression can ruin your mix, so use your ears.
A limiter is a compressor with a higher ratio (greater than 10:1) that
literally puts a limit on how loud you can make something. It comes from the
days of radio when there was a legal limit to how loud a broadcast could be, but
radio stations still wanted to seem as loud or louder than their competitors. A
limiter raises the average level of a track or mix while not letting the peaks go
beyond a fixed level - into the red, for instance. Like compression, limiting can
make your mix more exciting or ruin it completely. Listen!
There are four basic types of compressors: Tube, Optical, FET and VCA.
You may be familiar with our popular FET Compressor, the FET III. VCA
compressors don’t have a great reputation among professional engineers for
good reason - they are mostly feed-forward designs utilizing cheap RMS
detector chips and low-quality monolithic current-to-voltage convertors. The
Comp IIT is a very different, more complex VCA design that uses feedback, a
peak detector and an all-discrete Class A follower. We use the VCA like a FET
to get the sound we all love without the thermal instability and other problems
associated with FETS.
1.3 Why Transformers?
There’s a lot of talk these days about the advantages and/or
disadvantages of transformers in all sorts of audio gear. Some people prefer the
way audio gear with transformers sounds, some don’t. There is one inarguable
fact: gear without high-quality audio transformers is usually less expensive to
build.
So if transformers are expensive why do we need them?
First of all, it’s not just about the sound. Since the primary and secondary
of audio transformers are not physically connected they provide galvanic
isolation. That means there cannot be a ground loop between what comes
before the transformer and what comes after. In a piece of gear like the Daking
Comp IIT with input and output transformers there cannot be ground hum or
noise in a correctly wired system induced into the Comp IIT.
Second, transformers provide impedance matching. A transformer with the
appropriate primary and secondary turns ratio provides the optimum transfer of
voltage, or signal, from one stage to the next. This assures maximum gain
without distortion.
Third, great transformers sound great. Until the advent of monolithic ICs,
transformers were the main way to connect one piece of professional gear to
another. All the famous names in classic tube and early solid state audio gear
carefully chose high-quality transformers for their ability to provide galvanic
isolation, impedance matching and sound quality. That could mean neutral
sound or it could mean coloration, depending on what the designer wanted.
Although transformerless designs are often touted as not coloring the sound,
everything in the signal path colors the sound to some degree. A great
transformerless design can sound excellent and cost as much as a transformer-
based design. However good transformers are expensive, and the reality is that
most transformerless designs are cost-cutting moves, with sound quality taking
a back seat. The Jensen transformers we use are the best made.
1.4 Front Panel
Compression Knob
The Compression knob controls how much you compress the signal, from
Less to More. What is happening is that as you turn the control towards More
you are lowering the threshold at which compression begins. The lower the
threshold the more you compress a given signal. If the meter in the Comp
position shows too much compression with the Compression knob fully down
then the level coming into the compressor is too high and should be turned
down at the stage before. For instance, at the output of the mic preamp before
the Comp II when recording vocals.
Output Knob
The Output knob controls the amount of gain added to the signal after
compression. It goes from ~, no output, to 11. Since a compressor lowers the
peaks, the Output control raises the average level of the signal to compensate.
This is called “gain make-up”.
Attack
Attack controls the speed at which the Comp IIT responds to peaks in the
signal. Slow allows transients to go through uncompressed but reduces the gain
of what follows. Fast grabs the transients as well as the sustain of the signal.
Slow can be more subtle, fast more aggressive.
Release
Release is the speed at which the compressor, having compressed a
peak, gets ready to catch the next peak. Fast is fast release, obviously, and is
generally more aggressive. Auto adjusts the release time automatically
depending on the gain and the timing of the peaks in the signal you feed in.
Which one you use is a matter of taste - use whichever sounds better to you
when applied to the particular signal you’re compressing.
Ratio
Ratio determines how aggressively the compressor responds to the signal
you put in. Comp is a lower ratio and therefore compresses less. The signal will
maintain a greater dynamic range while still having peaks controlled. Limit is a
higher ratio that compresses more. Your input signal will have a smaller
dynamic range but higher average level. See Appendix I for a graph showing
how various compression ratios effect the signal output.
Bypass
Bypass turns compression off. Use it to compare the uncompressed and
compressed signal while setting up the compressor to record a track.
Meter and Meter button
The meter does double duty depending on the position of the Meter
switch. In the Comp position the meter shows you how much the peaks are
being reduced by the compressor. The needle sits at zero and moves to the left
to show gain reduction in negative numbers: -3 means the signal is being
reduced by 3dB, -5 means 5dB of gain reduction and so on. This will tell you if
you’re compressing too much or not enough. No matter how well you think you
can hear a compressor working, you should always monitor the gain reduction
meter to be sure.
With the switch in the Output position the meter is a normal VU meter that
shows you the output level of the compressor. If the level is too high or too low
you can adjust the level with the Output knob. With practice you will learn how
to set levels for all of the gear in your input chain. This is called “gain-staging”
and is key to getting quiet, distortion-free tracks.
Note that the Compression and Output controls are interactive - if you add
more compression the output level will go down, if you reduce the amount of
compression the output level will go up. It is usual for engineers to switch the
meter control back and forth between Comp and Output several times while
getting sounds to make sure the meter shows you have the amount of
compression you want as well as the output level you want. Also it’s wise to
keep in mind that singers tend to get excited and will sing harder when you hit
record than when you were getting sounds. Leave some room for that, and pay
close attention to make sure their levels aren’t out of control.
Stereo
In the Mono position the Comp IIT is two completely independent
compressors that can be used at the same time on different signals. In Link
mode the compressor listens to both sides of a stereo signal. Whichever
channel has the higher input gain from moment to moment will determine how
much you compress the stereo signal. In Link mode you must still set the front
panel controls for both channels - in most cases they would be set the same.
This is how you would use the Comp IIT on a stereo mix, for instance.
1.5 Back Panel
Audio Inputs and Outputs
The back panel contains balanced XLR inputs and outputs for each
channel, as well as a balanced 1/4” TRS output connector for each channel
which is wired in parallel to the XLR output. If you want an unbalanced output
you can use a 1/4” TS cable (a guitar cable) in the TRS jack. If you use both an
XLR cable and a 1/4” TS cable at the same time keep in mind you will be
making the XLR output unbalanced because they are in parallel. Always use
high-quality connectors and cables to wire your Comp IIT into your system.
Wiring is not the place to skimp.
Power Inlet
There is a power inlet on the back panel for connection to the power
supply included with the unit. Please run power cables away from foot traffic, in
a place where they’re not likely to be kicked out or tripped over.
1.6 Specifications
• Jensen input and output transformers
• Class "A" amplifier for Gain Make-Up
• All-metal construction with stainless steel chassis for noise immunity
• Custom aluminum knobs
• Power supply included
• Frequency response: 20Hz - 65kHz
• Inputs: 2 x XLR
• Outputs: 2 x XLR, 2 x TRS
• Maximum output level: <+30dBu
• THD at +4dBu input and no compression at 1kHz: Typical 0.02%, Max 0.035%
(22-22kHz, Un-Wtd)
• THD at +4dBu input and 2dB of compression at 1kHz: Typical 0.02%, Max
0.035% (22-22kHz, Un-Wtd)
• Noise: less than -80dBu, 22-22kHz
• 1U 19” rack-mount case: 17” (43.18cm) width, 8.375” (21.27cm) depth, 1.625
(4.13cm) height.
• Unit weight: 6.25 lbs. (2.83 kg)
• Box weight: 9.5 lbs. (4.31 kg)
• Box dimensions:!L: 29” (736.6mm)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!W: 14” (355.6mm)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!H: 6” (152.4mm)
Specifications are subject to change without notice.
1.7 Appendix I
Graph showing Comp IIT ratio response in Comp mode, Limit mode, and
Bypass:
Table of contents
Other Daking Audio Recording Equipment manuals
