BIAMP ZONE 4R ZONE4 wall control panel for music level & source select

The AD2022 is Avalon's fourth generation of fully discrete, symmetrical Pure
Class A microphone preamplifiers. The dual mono AD2022 includes the original
sonic capabilities and transparency of the M2, M22 and M5 preamplifiers plus
several additional features, including selectable microphone source loading for
optimized cable/mic matching, improved high-voltage Class A regulated power
supplies, two high Z instrument inputs, variable-passive high pass filter, teflon/
silver wiring and doubled plated circuit boards for superior low level signal transfer.
 
AD2022 FEATURES
Symmetrical Pure Class A design, two channels
Microphone and hi-Z instrument inputs
Gain switched 4dB steps plus +/- 3dB fine output trim 
Selectable microphone input impedance matching 
Low noise -126dB EIN
Ultra high quality, low-ratio, balanced input transformer
Balanced, high-current Class A output to +36dB
Large illuminated analog VU meters and twin peak LED's
Regulated phantom power supply +48v 
Input polarity phase reverse 
High headroom +36dB input before overload
Input -20dB pad for high level signals
Sealed silver relays for all signal routing
External AC 150w toroidal power chassis
Fully discrete Class A regulated audio power supplies
Deep, musical sound-stage, transparent amplification

MICROPHONE INPUT
The AD2022 incorporates the most advanced high-performance microphone
transformer available. Split low-ratio primary windings are carefully combined
within a custom mu-metal core for extended smooth frequency response and
very low distortion.  Sealer silver relays are used for minimal signal invasion. 
The input signal selector, high pass filter, polarity-phase reverse, +48v power
and the 20dB input attenuator all utilize local sealed relay operation. A variable
passive high pass filter provides a minimum phase shift design while eliminating
low frequency rumble, wind noise and mechanical vibration at sub sonic frequencies.

SYMMETRICAL PURE CLASS A DESIGN
Two 100% discrete, high-voltage, symmetrical Pure Class A signal amplifiers
are utilized per channel. The first operates in a cascaded-cascode FET
configuration while the second stage amplifier is fully bipolar. The twin amplifiers
share the total available gain requirement. This shared architecture increases
the high level headroom capability, improves transient response and doubles the
internal bandwidth of the ultra-high performance pure Class A signal amplifiers.
OUTPUT and METERING
High-current DC coupled, Class A discrete amplifiers are utilized for the output
drive interface with +36dB capability into all known loads.  Two large, high-quality
analog VU meters indicate accurate signal readings while bi-color LED's offers
peak indication at 0dB and +20dB.

AD2022 PREAMPLIFIER SPECIFICATIONS
 
Circuit Topology:  Twin cascode FET and bipolar low level signal amplifiers,
high-voltage, 100% discrete, symmetrical Pure Class A 
Input Type and Load:  Transformer balanced low-ratio, 50, 150, 600 and 1k5
ohm input load selection  
Maximum Mic Level:  +36dB balanced XLR pin 2 hot (with -20dB passive
attenuator) 
Maximum Instrument Level  +18dB at 100k ohms instrument input level,
standard mono 1/4 inch jack 
Input Attenuator:  -20dB resistive pre transformer primary, sealed silver relay 
Phantom Power:  +48v regulated 50mA capability, sealed silver relay 
High Pass Filter:  Passive, variable from 30Hz to 185Hz @ 6dB per octave,
sealed silver relay. 
Polarity Reverse:  Sealed silver relay on microphone input 
Gain Range Input:  +20dB to +64dB in 4dB steps 
Gain  Output Range:  +/- 3dB variable conductive plastic potentiometer 
Maximum Output Level:  +36dB balanced 600 ohms, DC coupled, discrete
symmetrical Pure Class A 
Output Type:  XLR connector, pin 2 hot 
Noise EIN Unweighted:  -126dB 150 ohm 
Noise 20kHz Unweighted:  -102dB 
Distortion THD, IMD:  0.05% nominal 
Frequency Response -3dB:  1Hz to 120kHz transformer limit 
System Bandwidth:  DC to 1MHz 
Output Meter:  High quality, illuminated analog VU meter 0dB = +4dB. 
Peak Meter:  Bi-color LED's 0dB and +20dB peak detection circuit. 
AC power supply B2T:  External toroidal 100V to 240V, 50-60Hz selectable,
150 watts maximum. 
Cables:  90V ac, 4 pin male power input connector, B2T required, internal
DC regulation  
Dimensions:  19 x 12 x 3.5 in (482 x 305 x 89mm) 
Weight:  15lbs (6.8kg) 
Dimensions - Shipping Carton:  24 x 21.5 x 7.5 in (610 x 546 x 190mm)  
Weight - Packed:  25lbs (11.4kg) 

The PRE-73 Mk2 is the first one-channel low-cost preamp on the market that is using a fully discrete signal path with three separate transformers for the balanced mic input, the line input and the output.

The circuit is very similar to the classical preamp section of the Neve 1073 pre/eq module with a corresponding sound character that is warm, punchy, sweet and musical.
This classical sound has been heard on countless recordings through the years and it is a versatile sound that works very well on most sound sources and in most genres.

The PRE-73 Mk2 has a maximum gain of 80 dB on the mic input and the gain range on the Line input is -20 to + 10 dB. There is also a high-impedance instrument input.

The PRE-73 Mk2 is perfect for almost any signal source, no matter if it's a microphone with a high or low sensitivity (like a passive ribbon mic), a syntheziser or sound module or an electric guitar or bass.

The input impedance of the microphone input can be switched between 300 and 1200 ohms, which makes it possible to affect the tone of most microphones. There is also phase switch and an simple 4-step LED signal level meter.

The output level control makes it possible to make fine gain adjustments and also to overload the main gain stage for more character and then lower the signal to a suitable level before the output stage.

The Mk2 update consists of:
- An unbalanced insert jack (nominal level about 18 dBu) added on the back panel for inserting units like the coming GAP EQ-73, a three band eq.
-  LED meter levels adjusted.
- 600 Ohm termination resistor and jumper added to power supply board (accessible from the inside of the unit).
- Revised Gain switch, turning the know clockwise now increase the gain.
- Reduced noise at high gains by a change to the power supply grounding scheme.

Applications

Console input extending for both Digital and Analog mixing
consoles in Studio, Live and Broadcast
Mic Pre-amps for ADAT/ Hard Disk/ Multitrack Recording
 
Innovation
If you love your compact Digital (or Analog) mixing console, but wish it had
more microphone inputs, ARX has the solution ? the 8 Pre: eight channels
of superb sounding Microphone Pre-amps in a compact 1 RU chassis.
The 8 Pre is the ideal console extender for those times when you need more
microphone inputs. Now you can put those unused line inputs to good use,
and who knows - the 8 Pre pre-amps sound so good that you?ll probably end
up using them all the time instead of the ones that came with your mixer!
Superb Audio Quality
The 8 Pre?s ultra low noise figures come from extensive use of premium
components plus care and attention to board design and layout. The result is
superb, transparent audio quality and the headroom to handle anything that a
mic can throw at it.
Gain is adjustable from 20 db through to 60 dB via a trim control on the front
panel, plus we?ve included a ?20dB Pad switch to tame the hottest condenser
mic output if required. The Clip status LED lights up 1 dB before the onset of
clipping, just to warn you you?re getting close.Phantom power is switchable in
banks of four channels: 1 through 4, 5 through 8. A Phase reverse switch is also
provided on each pre-amp channel to eliminate any close miking problems.
In short, the ARX 8 Pre is the mic Pre-amp that you?ll wish the console manufacturer
had used. It provides a unique solution to today?s multiple Mic Pre-amp requirements.

T E C H N I C A L S P E C I F I C A T I O N S
Input Gain 20dB to 60dB
Input Pad ?20dB
Input Impedance 4 KOhm
Input Headroom +23dB
Output Impedance 300 Ohm
Output Level (Max) +23dB
Frequency Response 20Hz ? 20KHz ±0.2 dB
Signal to Noise ratio (Gain set @ 20 dB)
?93dB Unweighted, ?99dB ?A? weighted
Distortion @ Unity Gain .004%, 20 Hz ? 10 KHz
Dynamic Range 116 dB
Phantom Power 48 VDC
Input Connectors Balanced XLR
Output Connectors Balanced TRS jack
Clip Indicator Illuminates 1 dB prior to clipping
Power Requirements 100/120 V AC, 220/240 V AC
Weight 5 lbs/2.2 Kg
Dimensions 19“W x 1?“H x 6“D, 482 x 44 x 155mm

• • Ultra-high quality 8-channel A/D and D/A interface for virtually any digital recording/mixing environment
  • 8 state-of-the-art MIDAS designed Mic Preamplifiers
  • Phantom power on all microphone inputs
  • Reference-class Cirrus Logic 24-bit converters for ultimate signal integrity
  • Processes 48 and 44.1 kHz sample rates
  • External sample rate synchronization via word clock or ADAT input

• Optical ADAT in/out interface for ultimate compatibility
• All mic/line inputs routed to the ADAT output
• ADAT input routed to all Line outputs
• “Planet Earth" switching power supply for maximum flexibility (100 - 240 V~), noise-free audio, superior transient response plus low power consumption for energy saving
• High-quality components and exceptionally rugged construction ensure long life
• Conceived and designed by BEHRINGER Germany

At PreSonus, weʼve been designing preamps for a long time, and we always focus on audio quality first. So when we decided to upgrade our popular TubePre V2, we focused on improving an already high-quality sound—without jacking up the price. Like the originalTubePre, the new version is a fully professional tube preamp, with a dual-servo (no capacitors) gain stage that lets you boost the program signal to smoking hot levels without significantly increasing the background noise. Discrete components and high-voltage operation offer dynamic range and detail not found in other single-channel tube preamps in its class.

Housed in a rugged case, the TubePre V2 rear panel sports separate unbalanced, ¼” instrument and balanced, XLR mic inputs and unbalanced ¼” and balanced XLR line outputs. Weʼve included all of the extras you need for professional operation including a high-pass filter, phantom power for condenser mics, polarity reverse switch, and a backlit VU meter.