AVALON AD2055 DUAL MONO PURE CLASSA PARAMETRIC MUSIC EQUALIZER

The AD2055 combines 100% discrete, pure class A signal amplifiers with state-of-
the-art passive and active filter topologies. The AD2055's unique circuitry delivers
very high resolution transient detail at the operational extremes of real world equalization
demands. The AD2055 auto-bias DC servo loop control eliminates the need for all
interstage capacitor coupling. The AD2055 breathes life into all musical performances!
 
AD2055 FEATURES
Pure Class A, 100% discrete design
Smooth musical detail and sonic excellence
Minimum audio signal path
Dual mono operation
Transparent active and passive filter design
High headroom +30dB Very low noise -94dB
Fully balanced inputs and outputs
DC coupled, no transformers in audio path
Switched frequencies in high and low bands
Mid bands use X10 frequency for extended range
Wide bandwidth -3dB 1Hz to 450kHz
Low distortion less than 0.5% THD and IMD
All signal routing with sealed silver relays Conductive
plastic potentiometers for low noise
External 150W toroidal power supply 100% discrete
power supplies for audio path
Long lasting, stainless steel hardware
 
SONIC EXCELLENCE
The Avalon AD2055 Pure Class A music equalizer is the most powerful, low noise
parametric equalizer available today. Designed to optimize absolute signal integrity
and musical performance, the AD2055 combines the best of active and passive filter
topologies with sonic excellence unequaled by lesser designs. The AD2055 is the
perfect solution for two buss music-program equalization, special instrument EQ and
FX applications and ultra high performance mastering studio's.

Features include state-of-the-art, balanced 100% discrete, Pure Class A signal amplifiers,
practical user features and rugged hardware designed to deliver true high performance
audio for many years. 

PASSIVE-ACTIVE FILTER DESIGN
Avalon equalizers feature the unique combination of both active and passive filter EQ designs.
This special combination enables the AD2055 to deliver high speed transient detail at the
operational extremes of real-world equalization demands. The passive high and low bands offer
alternate musical tone range to the full function active parametric mid bands. Passive equalizers
have long been a favorite with music lovers around the world.  Full bodied, powerful (up to +/-32dB,
64dB range !) and sweet frequency selections are the benefits of the passive high-low EQ bands.
The full bandwidth twin mid bands provide variable frequency selection (X10 frequency multipliers
for very wide range), variable Q (width) and amplitude control.

MINIMUM SIGNAL PATH DESIGN
Avalon's advanced true symmetry design offers high-voltage, large headroom, extended bandwidth
and very low noise. The use of 100% discrete, Pure Class A signal amplifiers give the serious music
professional unlimited sonic character and a natural harmonic detail that enhances the program
material and becomes one with the music itself. The Avalon AD2055 breathes life!

AD2055 SPECIFICATIONS
Circuit Topology  High-voltage 100% discrete, balanced and symmetrical
Class A 
Output Gain Range  Unity Gain 
Maximum Input Level  +30dB balanced XLR pin 2 hot 
Maximum Output Level  +32dB balanced 600 ohms, DC coupled, high-current
discrete Class A 
Input / Output Type  XLR type, pin 2 hot balanced 
Noise 20kHz Unweighted  -94dB (EQ in) 
Distortion THD, IMD  0.5% (typical 0.05% at +6dB 1kHz) 
Frequency Response -3dB  1Hz to 450kHz (input band limited) 
Equalizer Type  Passive high and low bands plus two fully parametric mid
bands 
Bypass  Hard-wire relay bypass for equalizer in-out 
Low Band F1  Passive, amplitude to -32dB to +32dB shelf or peak-dip curve 
F1 Frequency Range  Switched 10 position 18Hz, 25, 30, 50, 72, 100, 150, 215,
300, 450Hz 
Mid Band F2  Active, amplitude to -16dB to +16dB peak-dip curve 
F2 Frequency Range  Variable 35Hz to 450Hz (x10) 350Hz to 4k5Hz, Q (width)
0.3 to 3.0 
Mid Band F3  Active, amplitude to -16dB to +16dB peak-dip curve 
F3 Frequency Range  Variable 160Hz to 2k0Hz (x10) 1k6Hz to 20kHz, Q (width)
0.3 to 3.0 
High Band F4  Passive, amplitude to -26dB to +26dB shelf or peak-dip curve 
F4 Frequency Range  Switched 10 position 1k5Hz, 2k5, 3k5, 5k, 7k2, 10k, 12k5,
15k, 20k, 25kHz 
AC-DC Power  External AC supply, 150w toroidal transformer, 4 pin cable 90v
isolated, 
(B2T Power Supply Included)  100-240v selectable 50/60Hz, 150w max 
Dimensions  19 x 3.5 x 12 in (482 x 88 x 305mm) 
Shipping weight  30lbs (13.6 kg) 

Features
Four Independent Compressor Channels
Channels 1 and 2, 3 and 4 are stereo linkable
7 LED Gain Reduction metering
Balanced XLR Inputs and Outputs
Sidechain Insert points
Intuitive, user friendly layout
Flawless performance
 
The sheer amount of effects and signal processors necessary for today's standards
of audio production puts a great strain on the available space in equipment racks,
both in the studio and on the road.So, ARX would like to introduce the ARX Quadcomp.
An all-new upgrade of the classic award-winning ARX Quadcomp?, the very first four
channel 1 RU compressor.You?ll notice that we haven?t strayed very far from our
original design concept. The Quadcomp  is still four variable ratio Compressor/ Limiters
neatly housed in a compact all steel 1 RU package. However, all new low noise/low
distortion circuitry, better metering plus XLR inputs and outputs put the Quadcomp
in a class of its own.
More Control, Less Space
On the front panel, each channel has the 'industry standard' individual controls for Threshold,
Compression Ratio and Output, plus a new 7 LED Gain Reduction display for accurate visual
indication of the amount of gain reduction being applied to the program, and an IN/OUT
hardwire bypass switch.In addition to this, each channel has a blank numbered panel to write
on for easy confirmation of compressor assigns.
Precision Circuitry
Internally, each compressor uses Class A VCAs and true 2 pole averaging RMS/DC converters
for low distortion and accuracy, plus program dependent attack and release time, which
automatically determines optimum compressor response.
Balanced Inputs and Outputs
The rear panel has true differential Balanced XLR Inputs and Outputs for each compressor.
Each compressor has a TRS jack Sidechain access insert point, for frequency sensitive
compression, De-essing, etc. in conjunction with an external equalizer (such as the ARX EQ260).
Compressor pairs 1 and 2, 3 and 4 also have rear panel mounted Stereo Link switches for accurate
stereo tracking. When switched IN, the first channel becomes the master and controls all the functions
of the second except Output gain.
Universal AC Power
AC power range is switchable 100 to 120V, or 220 to 240V, and is connected to the unit via
a standard IEC connector, with built-in fuse and voltage switch.
Whatever the application ? Channel insert, Bus insert, Master Outputs, Monitor outputs,
Crossover outputs, the Quadcomp II?s unique High Density design, precision Low Noise circuitry
and clean uncluttered layout make it a truly useful audio tool for all applications.

T E C H N I C A L S P E C I F I C A T I O N S
Input Impedance
Balanced 20 Kohms, Unbalanced 10 Kohms
Input Headroom + 20dB
CMRR >50dB, 20 Hz?20 KHz
Output Impedance
Balanced 300 ohms Unbalanced 150 ohms
Output Level (Max) + 20 dB
Frequency Response 20Hz-20KHz ±0.5dB
Signal to Noise ratio
-93 dB Unweighted, -98 dB ?A? weighted
Distortion .015% THD @ 0dB,1KHz
Dynamic Range 108 dB
Attack and Release Times Program dependent
Metering
7 LED display: ?1, 2, 3, 6, 12, 18, ?24 dB
Sidechain Insert Impedance 10 Kohm
Power Requirements
100/120 V AC or 220/240 V AC
Weight 5 lbs/2.2 Kg
Dimensions
19“W x 1?“H x 6“D, 482 x 44 x 155mm
Input Connector type Balanced XLR
Output Connector type Balanced XLR
Sidechain Insert Connector TRS Jack

Front Panel Controls
Hardwire bypass IN/OUT switch
Threshold, Ratio and Output Gain controls
7 LED Gain Reduction display
Marker panel for labelling compressor assigns
Stereo link status LEDs
Rear Panel Connectors
Input and Output balanced XLR connectors
TipRingSleeve Sidechain insert connectors
Channels 1 and 2, 3 and 4 Stereo link switches
IEC AC mains connector with inbuilt fuse and
voltage change

GENERAL DATA
Power Supply 220 / 110V 25 VA
Dimension 434x351x44mm (1 rack unit)
Weight » 4 Kg
MEETING INTERFACE IN / OUT
Connector DB 9 female
Nominal in / out audio level 0 dBm
Input impedance 600 W / 10 KW (selectable)
Output impedance 100 W
* nominal line level: - 6 dBm
** it can vary depending on characteristics of telephone line
All measurements are intended at 1 kHz.
AUDIO PROGRAM IN / OUT
Connectors XLR, electr. balanced
Input impedance 600 W / 10K W (selectable)
Output level * - ¥ ¸ + 16 dBm
Output impedance 100 W
Noise on Receive output 2-Wire separation £ 25 dB**
4-Wire separation £ 70 dB
2-WIRE SECTION
Connector RJ11
Nominal input level - 6 dBm
Nominal output level - 6 dBm
Compensation mode Electronic, transf. decoupled
Impedance 600 W
4-WIRE SECTION
Connector Terminal block
Impedance 600 W
Nominal TX level 0 dBm
Nominal RX level 0 dBm

Features
Unique High Density design puts SIX gates in
minimum rack space
Intuitive, 'user friendly' layout
Balanced Inputs and Outputs
Fast, low noise opto-coupler circuitry
Sidechain/Key Input points on each channel
Hardwire Bypass switch on each gate
Flawless performance in any audio environment

The sheer amount of effects and signal processors required for today's
standards of audio production puts a great strain on the available space
in equipment racks, both in the studio and on the road.
So, in order to give engineers more control in less space, we've created
the ARX Sixgate; Six full function noise gates neatly housed in a compact,
all steel 1 RU package, without sacrificing features or quality.
Why Six gates?
Research shows that the majority of noise gates get used on drum kits,
which means using typically 5 to 6 gate channels. Compare this to the
two or maybe 4 channels that most other units have, and you'll see the
reason for the Sixgate's success.And, by using a minimalist approach to
drum gates, the ARX Sixgate has enough gates left over for backing vocals
and other instruments.
Industry Standard controls
Front panel controls for each gate consist of the 'Industry Standard' controls
for Release, Depth and Threshold, plus Red and Green LED displays to indicate
Gate Open or Closed status, and an IN/OUT hardwire bypass switch.
In addition to this, each gate has a blank panel to write on for easy confirmation
of gate assigns. No more pieces of masking tape stuck everywhere!
Ultra Low Noise
Internally, each gate has proprietary ARX ultra low noise high-speed opto-coupler
circuitry with program dependent Attack time, which tracks the incoming signal to
automatically determine optimum gate response.
Balanced Inputs and Outputs
The rear panel features true differential Balanced Inputs and Outputs for each gate,
on insulated TRS jack connectors.Each gate channel also has Individual Key Inputs/
Sidechain access insert points which can be used either for gate control by an external
signal, or for frequency sensitive gating (when used in conjuction with an external
equalizer such as the ARX EQ260).
Universal AC Power
AC power range on the Sixgate is a universal 100 to 120V or 220 to 240V, and is
connected to the unit via a standard 3 pin IEC connector, with built-in fuse and voltage
switch.
The Sixgate's unique combination of High Density design, intuitive 'user friendly' controls,
and clean uncluttered layout make it a truly useful audio tool for all applications.

T E C H N I C A L  S P E C I F I C A T I O N S
Input Impedance
Balanced 20 Kohms, Unbalanced 10 Kohms
Input Headroom + 22 dB
CMRR >60 dB, 20 Hz-20 KHz
Output Impedance
Balanced 300 ohms, Unbalanced 150 ohms
Output Level (Max) + 20 dB
Frequency Response 20Hz to 20KHz ±0.2dB
Signal to Noise Ratio
Gate Closed: -95 dB Unweighted, -105 dB 'A' weighted
Gate Open, Depth Minimum: -93.5 dB Unweighted -98dB
'A' weighted
Distortion 0 .01% THD @ 0dB,1KHz
Dynamic Range 125 dB
Attack Time Program dependent using high-speed
opto-couplers
Release Time User variable
Input and Output Connector type Balanced Jack
Sidechain Insert Connector TipRingSleeve Jack
Sidechain Insert Impedance 10 Kohm
Power Requirements 100/120 V AC, 220/240 V AC
Weight 5 lbs/2.2 Kg
Dimensions
19“Wide x 13/4“High x 6“Deep; 482 x 44 x 155mm

Front Panel Controls
Individual Release, Depth and Threshold controls
Hardwire bypass IN/OUT switch
Open/Closed gate status LED
Marker panel for labelling gate assigns
Rear Panel
Balanced Inputs and Outputs, on Balanced jack
connectors
Sidechain Insert/Key Input TipRingSleeve jack on
each channel
AC input connector, with voltage switch and fuse 

The DPR-504 is a 4-channel noise gate.

Each channel features:
A parametric key filter with key filter listening.
Simultaneous key level and threshold metering with average and
peak metering.
A gate status LED.
A RELEASE/HOLD control (hold tracks proportionally with release
times).
Attack switchable auto/fast (auto tracks signal dynamics for optimum
setting).
Link (links two channels together).
Key source allows external triggers.

The Range switch selects between 7OdB and 2OdB gating depth to
provide alternative release profiles.
The unit features electronically balanced inputs and outputs.