Daking Audio FET III User manual

Daking Audio
FET III Stereo Compressor/Limiter Manual
VERSION 1.4
Hendrik David Gideonse XIX
3/26/2010

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Safety Considerations
1. Read, follow and keep these instructions.
2. Heed all warnings.
3. Do not use this equipment in or near water. Do not place liquids on or near the
device because the device might be damaged during a spill.
4. Clean only with a soft dry cloth.
5. Do not block any ventilation openings. Install in accordance with the
manufacturer‟s instructions.
6. Use only Daking supplied power supplies to prevent damage to your device or
create safety hazards.
7. Do not install near any heat sources such as radiators, heat registers, stoves, or
other apparatus (including amplifiers) that produce heat.
8. Do not defeat the safety purpose of the polarized or grounding-type plug. A
polarized plug has two blades with one wider than the other. A grounding-type
plug has two blades and a third grounding prong. The wide blade or the third
prong are provided for your safety. If the provided plug does not fit into your
outlet, consult an electrician for replacement of the obsolete outlet.
9. 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.
10. Only use attachments/accessories specified by the manufacturer.
11. Unplug this device when unused for long periods of time.
12. Refer all servicing to qualified service personnel. Servicing is required when the
apparatus has been damaged in any way, such as when a power-supply cord or
plug is damaged, liquid has been spilled or objects have fallen into the apparatus,
the apparatus has been exposed to rain or moisture, does not operate normally, or
has been dropped.
13. Do not overload wall outlets and extension cords as this can result in a risk of fire
or electric shock.

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Contents
1Daking Audio FET III Stereo Compressor/Limiter Manual....................................... 5
1.1 About Daking Audio............................................................................................ 5
1.2 Quick Start Guide................................................................................................. 5
1.2.1 Don‟t read the manual! ................................................................................. 5
1.2.2 Basic Set Up.................................................................................................. 6
1.3 The Audio Path and the Sidechain Path............................................................... 6
1.4 Front Panel ........................................................................................................... 8
1.4.1 In General: Rotary Switches and Potentiometers ......................................... 8
1.4.2 The Threshold Knob (-10 dB to +10dB) ...................................................... 8
1.4.3 Ratio Knob (1.5:1, 2:1, 3:1, 5:1, 10:1, 20:1)................................................. 8
1.4.4 Attack Knob (from 250 μs to 64 ms) .......................................................... 10
1.4.5 Release Knob (from 500 ms to Dual Time Constant Auto)........................ 10
1.4.6 HPF (High Pass Filter: from Off to 200 Hz)............................................... 12
1.4.7 Make-up Gain Knob (from +0dB to +11dB).............................................. 12
1.4.8 VU Meter .................................................................................................... 12
1.4.9 3-Way Meter Switch................................................................................... 13
1.4.10 Bypass Switch............................................................................................. 13
1.4.11 Link: Dual Mono to Stereo......................................................................... 13
1.5 Back Panel.......................................................................................................... 14
1.5.1 In General: XLR Connectors ...................................................................... 14
1.5.2 Line Input (XLR or ¼” TRS)...................................................................... 14
1.5.3 Line Output (XLR) ..................................................................................... 15
1.5.4 +48V DC with a 6 pin DIN connector........................................................ 15
1.6 Signal Flow: Patching Into and Out of Your FET III Compressor.................... 15
1.6.1 Mic Pre to FET III to Audio Interface or Mixer......................................... 15
1.6.2 Connecting Via a Single Insert Jack........................................................... 16
1.6.3 Via a Patch Bay........................................................................................... 18
1.6.4 Stereo Setup as a Bus Compressor for Mixing or Mastering...................... 19
1.7 Typical Uses of a compressor ............................................................................ 20
1.7.1 Why do I need a compressor anyway? ....................................................... 20
1.7.2 Keeping a vocal performance out front ...................................................... 20
1.7.3 Keeping bass consistent.............................................................................. 21
1.7.4 Fatten kick drums........................................................................................ 21

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1.7.5 Limiting to preventing overload, clipping and distortion........................... 21
1.7.6 Pointers and General Principles.................................................................. 22
1.8 Specifications..................................................................................................... 23

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1 Daking Audio FET III Stereo Compressor/Limiter Manual
1.1 About Daking Audio
Congratulations! You‟ve purchased a FET III Stereo Compressor/Limiter, a
very high end piece of gear! The FET III uses all discrete transistor Class A
circuits, THAT Corporation differential amps 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‟d own for life, not some
passing fancy you‟d leave in the dust once you figured what the good stuff
sounds like. This IS the good stuff.
-Geoff Daking
1.2 Quick Start Guide
1.2.1 Don’t read the manual!
Most of you will already know how to use a compressor perfectly well and
might be even a little offended at the idea of reading the instruction
manual. So don‟t read it. This manual is not for you.
This manual is for someone that knows enough to buy the very best
(Daking of course!), but doesn‟t have a lot of experience using recording
gear.
You might be a bass player who just got a DAW and wants more control
over your dynamics in your home studio. You might be a student that just
got a check from Mom & Dad and wants to go buy something nice for
yourself.
You might be the guy standing ankle-deep in a
pool of salt water, trying to yank the grounding pin
off your mixer‟s power cord so you can plug it into
your 2-prong ungrounded outdoor outlet.
This manual is especially for you!
Whenever you see the Duh! Guy, you can be
assured that most professionals will already know

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this stuff. Be sure to explain this stuff to your friends in a snotty and
condescending tone, so you too can be part of the tradition of know-it-all
engineers and recordists!
1.2.2 Basic Set Up
Your compressor can be used in a variety of different ways and patched
into the signal chain of many different set-ups. The FET III can be used
while you are tracking a microphone, while you are mixing tracks down,
and in mastering scenarios.
The FET III can be used in both dual mono and in stereo modes.
1. Patch the outputs of your line-level audio devices (like a mic
preamps or an insert send on your console) to the Line Input jacks on the
rear of the compressor.
2. Patch the Line Outputs on the rear of the compressor to the input
of your line-level audio device (like the insert return on your console)
3. Attach 6-Pin DIN cable on the power supply to the back of the
compressor
4. Plug the power supply into a grounded outlet, preferably with AC
line filtering, surge suppression and voltage regulation.
Get compressin‟!
1.3 The Audio Path and the Sidechain Path
One important concept to understand about compression is
the difference between the audio path and the sidechain
path. The audio path is the audio that is going into the
compressor, being processed by the compressor, and then
coming out of the compressor. The sidechain path is the
audio that is used to determine when and how the
compressor will behave. The simplest compressors
operate by using the audio input for both the audio path
and the sidechain path. More versatile processors allow you to alter the sidechain
audio, use a different audio source or blend two sources together. The FET III
allows you to filter the sidechain audio and to blend the audio from channels 1
and 2 together in the chain. This allows much more precise control of how the
compressor works both in mono and stereo modes.

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Figure 1 FET III Block Diagram

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1.4 Front Panel
1.4.1 In General: Rotary Switches and Potentiometers
Your compressor is equipped with both rotary switches (Ratio Control)
and with precision potentiometers. Switches make a big click when you
turn them and potentiometers offer a smooth continuously variable feel as
you rotate them.
One of the big advantages of switches is that you can reproduce the same
settings over and over again. The big advantage of continuously variable
potentiometers is that you can get all of the setting in-between the
positions on the switch. The FET III uses switches on the Ratio control so
that it is easy to use the exact same ratio on both the left and right side of
the compressor.
1.4.2 The Threshold Knob (-10 dB to +10dB)
The Threshold knob controls at what level in decibels the compressor
starts to work. When a signal goes above the Threshold, the compressor
starts to attenuate (reduce the level of) the signal. Signals below the
threshold get left alone. If the knob is set to “0,” then all the sounds above
0 dB will be reduced in gain and the sounds below will be untouched.
If you want more compression, then you should lower the Threshold. If
you want less compression then you should raise the Threshold. See
Figure 2.
1.4.3 Ratio Knob (1.5:1, 2:1, 3:1, 5:1, 10:1, 20:1)
The Ratio knob controls how much attenuation (gain reduction) happens
to the signal above the Threshold. The Ratio is a comparison of the input
to the output, when the signal is above threshold.
For instance, imagine you have set a 3:1 ratio and set the Threshold to 0
dB. Note in Figure 2 below, the audio input signal rises +9 dB above 0
dB Threshold. As you can see the output signal is only +3 dB above
Threshold. The increase of 3 dB input above Threshold yields only 1 dB
above the Threshold output.
Higher ratios are easier to hear because they are making a bigger change
from the original. So if you are trying to be subtle, stick with generally
lower ratios. Sometimes of course you will need to use heavy
compression to achieve the results that you are after.
Compressors with ratios of 10:1 or higher are called limiters. Limiters are
often used after preamps to protect recorder inputs from sudden overloads,
like intermittent screaming or someone dropping a mic during a live
recording. The limiter helps prevent the recording from being ruined!

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Limiters can also be used to set a volume limit for a playback system to
protect speakers from damage.
Figure 2 Threshold and Ratio Settings with Meter Readings

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1.4.4 Attack Knob (from 250 μs to 64 ms)
Unfortunately, the Attack knob has nothing to do with using the power
supply as a weapon or stopping the guitar player from playing too much!
The Attack knob controls how fast the compressor turns on after a signal
crosses the Threshold. If the Attack is set slow, the compressor will react
slowly to transients above threshold. If the Attack is set fast, the
compressor will react the instant the transient exceeds the Threshold. Fast
settings are to the left and slower settings are to the right. See Figure 3
below.
If you set the compressor‟s Attack too fast the transient will be attenuated
too much and the power of the instruments will be reduced. When drums
sound wimpy or flat, it is often because the Attack settings are too fast. If
you set the Attack to slow, you might miss the transients altogether and
not compress the audio enough.
If you have a lot quick explosive peaks, speed up the attack to prevent
overloads of downstream devices. If you don‟t have many fast peaks, use
slower settings to level out small dynamic changes in a vocal performance
or bass part.
Your Daking compressor is fast enough to control even the most intense
transients from drums and percussion. The fastest attack time on the FET
III is 250 μs (1/4 of a millisecond) while the slowest attack time is 64 ms.
1.4.5 Release Knob (from 500 ms to Dual Time Constant Auto)
There are NO hostages!
The Release knob controls how quickly the compressor stops
compressing after the signal drops below the Threshold. See Fig
3 below. The Release control can be used to lengthen sustain
times and to blend audio signals together. When Release times
are faster, the compression may be less obvious and be more
transparent. If Release times are set improperly the compressor
may sound as if it is causing the audio to swell, pump or breathe.
The Release time and behavior of a compressor is very important to the
signature sound of the unit. The FET III has release times that range from
about a half second to a dual time constant release based on the Audio &
Design (Recording) Limited‟s famous F760X 'Compex' limiter. When the
FET III is in full Auto mode, the release starts out pretty fast, but then
slows down. The total release time can be as long as 7-8 seconds, but dual
time constant makes it sound very natural. See Figure 3.