GOLDEN AGE PRE73 MK3 Microphone preamp

The PRE-73 MKIII is a one-channel vintage style microphone-, line- and instrument preamplifier. The signal path uses only discrete components like resistors, capacitors and transistors. The in- and output is transformer balanced, using two different transformers, each one optimized for its purpose. This is the way audio components were built before integrated circuits became available.

The circuit used in the PRE-73 MKIII is similar to the preamp section in the classical 1073 module with a corresponding sound character that is warm, punchy, sweet and musical. These classic characteristics have 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 essence of this sound is now available at a surprisingly low cost, making it available to nearly everyone.

Features  :

• Vintage Style electronics. No intergrated circuits in the signal path.

• Maximum gain in MIC mode is 80 dB, enough to handle passive ribbon mics with quiet sound sources.

• GAIN switch range 20 - 80 dB. GAIN/LINE mode switch, gain is reduced by 30 dB in LINE mode.

• Selectable two position high frequency AIR boost eq, 3 or 6 dB @ 30 kHz.

• Selectable 6 dB/octave two frequency high pass filter at around 40 (HP1) and 170 Hz (HP2).

• Tantalum capacitors in the signal path.

• Switchable impedance in MIC mode, 1200 or 300 Ohms, will change the tone of most mics. The input impedance in LINE mode is 10 kohm.

• Switchable phantom power and absolute phase.

• A high-impedance instrument input for any sound module, electric guitar or bass.

• A simple but effective 4-step LED output level meter.

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

• Combo XLR/TRS input jack and separate output XLR and TRS jacks for flexible connections.

• Insert jack for inserting EQ´s and other units.

• Selectable 600 ohm output termination.

• The pcb is prepared for the Carnhill input transformer.

• External power supply to avoid interaction with the audio circuits and transformers.

• A solid build quality that will last many years of normal use.

The MKIII has the following new features compared to the MKII:

• Tantalum capacitors in the signal path.

• Selectable two position high frequency AIR boost eq, 3 or 6 dB @ 30 kHz.

• Selectable two frequency high pass filter, 6 dB/octave at 40 or 170Hz.

• The pcb is prepared for the Carnhill input transformer.

• Revised and less complicated GAIN switch with a separate switch for MIC/LINE selection.

• All GAIN settings can also be used in LINE mode .

PreSonusʼ popular Class A XMAX preamps are widely lauded for their clarity and transparency. Our tube preamps are beloved for their warm, smooth sound. With the Blue Tube DP V2 dual-path mic/instrument preamp, you get both types of high-quality sound in one unit.

Now weʼve improved on the classic unit with the BlueTube DP V2. The solid-state path now feeds PreSonusʼ top-of-the-line Class A XMAX™ mic preamplifier with 80 dB of variable gain—an upgrade from the original BlueTube DPʼs solid-state stage.

You still get all the secondary features you expect in a professional-grade preamp: 48V phantom power, an 80 Hz high-pass filter, -20 dB pad to control hot input signals, and a polarity-reverse switch. Each channel has an illuminated VU meter so you can visually monitor your input levels.

A Tube Drive control provides a wide range of sounds: when itʼs clicked off, youʼre using the solid-state preamp for quiet, transparent amplification; when itʼs engaged, your signals flow through the tube preamp, and you can achieve anything from gentle warmth to edgy distortion.

    2 input channels, each with:
        High-headroom Class A XMAX™ mic preamplifier with 80 dB gain range
        12AX7 vacuum tube gain stage
        Tube Drive tube-saturation control
        48V phantom power
        80 Hz high-pass filter
        -20 dB pad to reduce hot input levels
        Polarity-reverse switch
        Illuminated analog VU input-level meter

    Input/Output
        2 balanced combo mic/unbalanced instrument inputs
        2 balanced XLR main (L/R) line outputs
        2 unbalanced ¼” main (L/R) line outputs

    Physical
        Compact 1/2U chassis
        External 12 VDC, 1A power supply

The PreSonus HP60 is the most flexible and advanced headphone amplifier system available for professional and project recording studios as well as live sound in-ear monitoring systems. Loaded with six independent,
loud and clear headphone amplifiers, the HP60 features dual stereo inputs as well as external input, for each
channel allowing you to mix between three stereo audio streams (mix A, mix B, and external input). Stereo output is also available on each channel to send line level headphone channel mixes to additional headphone amplifiers or monitor systems. Each channel features headphone level, mix control between A and B inputs, external input volume, mute and mono. The HP60 also features talkback via external XLR microphone input. Common set up of the HP60 in a recording session is to send the main control room mix to input A. Send the click track to input B. Send the each band member direct recording input to each channelʼs external input (more me). This will allow each band member to create a mix between the main mix, the click track and themselves. The HP60 is the ultimate headphone amplification system delivering loud and clear headphone mixes for real-world recording situations.

Features:
-Six independent ultra low noise, high output headphone amplifiers (150 mW per channel)
-Two sets of stereo inputs (A and B) with balanced TRS connectors
-Stereo external input point on each channel for "more me” with trim control
-Mix control between inputs A and B
-Talkback with external XLR microphone with control
-Direct stereo line output on each channel

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.

Features
Superlative sound
Studio quality mic preamp
Total control - Input Gain, EQ contour, Output Gain,
Overload indicator
Multiple output connectors
XLR/jack combo input 
Switchable 48 V DC Phantom Power for condenser Mics
Compact, computer friendly package
Needs no external power supply
 
ARX is proud to introduce the e-pre - the ultimate microphone pre-amp for
hard disk recording, designed by audio professionals, not computer engineers.
The all-new e-pre is so much a part of your system that it fits right into a spare
5?" slot in your computer case! It's the perfect tool for all your day-to-day
recording requirements. No equipment racks to plug in, no masses of cabling to
connect - the e-pre is ready and waiting when you need it.
The e-pre is a studio quality microphone pre-amp using the same internal components
as high end mixing consoles, built into a compact, computer friendly package.
It has controls for:
Input Gain - fully variable from 10dB through to 60dB to suit all types of microphones,
plus switchable 48 V Phantom Power to enable condenser microphones to deliver
their best.
A Contour control for EQ sweetening, providing fast, easy access to a whole range
of useful EQ curves
Output level control - fully variable to match the e-pre's output to the input of the sound
card. From -10dB consumer cards through to +4dB for professional sound cards, the
e-pre can handle it.
Multiple output connectors match up with any kind of sound card, including mini jacks,
standard jack, RCA (phono) plugs, and even a connector to link to the internal CD ROM
audio input of your sound card (if fitted).
We've even fitted a 12 VDC input connector on the rear to enable the e-pre to run from an
external power supply if required (eg for use with notebook computers or stand-alone use).

Any way you look at it, the e-pre by ARX is the total professional microphone pre-amp for
all your hard disk recording needs

e-pre Benefits
Professional Balanced XLR mic input
True 48v phantom power
Runs into the Line input of ANY sound card - uses the card you've already paid for
High headroom = clean recordings
Smart EQ
Compatible with non-computer audio equipment
Professional performance and specs in a user friendly package
 

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
Mic 2 K Ohms Balanced; XLR type Pin 1 Audio Ground, Pin 2 +, Pin 3-
Line 25 K Ohms Balanced, ?" TRS jack Tip +, Ring , Sleeve Audio Ground
Phantom Power Voltage Switchable +48 V DC on XLR Pins 2 and 3
Max Input Level Mic +15 dB, Line +20 dB
Input Gain 10 dB Minimum, variable to 60 dB Maximum
Output Level -10 dB variable through 0 dB to +4 dB
Overload Indicator Measured at all Gain points throughout the circuitry
Output Noise -90 dB Unweighted, -97 dB 'A' weighted
(Measured with Gain nominal 20 dB, Output level -10 dB)
Frequency Response 20 - 20 KHz ± 0.25 dB
Distortion
100 Hz 0.0085%
1 KHz 0.008%
10 KHz 0.0083%
(Measured with Mic Gain 20 dB, Output 0 dB)
Power Requirements 12 V DC from either computer supply or external supply
(external power supply not included in e-pre package)
Size 148mmW x 42mmH x 150mm D (5?“W x 1?H x 6“D)
Weight Under 1 Kilo (2.2 lbs)
 

The U5 high-voltage DI-preamp combines a unique passive tone selector with a variable
gain preamp and filter. The high input impedance accepts a wide variety of signal levels
and instruments from acoustic guitars to high-output active bass guitars and keyboards.
The U5 direct box is loaded with sonic character and user features professionals demand.

U5 FEATURES
Pure Class A, 100% discrete design
Smooth musical detail and sonic excellence
Variable gain preamp to +30dB.
Dual microphone and line outputs
Hi-Z   3,000,000 ohm input impedance
Very low noise -100dB
High headroom +30dB
Six tone bank selections.
DC coupled Class A output for superior bass
High cut switch eliminates noise
LED active signal indicator
Headphone monitor output jack
Low distortion less than 0.5% THD and IMD
High level 400 watt speaker input
Active to thru selector - ground isolation switch
100% discrete power supplies for audio path
Internal toroidal power supply for low noise
Long lasting, stainless steel hardware
 
SONIC EXCELLENCE
The Avalon U5 Pure Class A instrument DI & preamplifier is the most powerful direct box
available today.  Designed to optimize absolute signal integrity and musical performance,
the U5 includes many features and sonic excellence unequaled by lesser designs. The
U5 is ideal for bass guitar and acoustic instruments, electric guitars, keyboards, synthesizers
and low output pickups. 
Features include state-of-the-art, high input impedance input stage for zero load effect on
sensitive pickups and keyboards, 100% discrete, Pure Class A signal amplifiers, practical
user features and rugged hardware designed to deliver true high performance audio for many
years. 
DESIGNED FOR DEEP & CONTROLLED BASS
Avalon U5 DI-preamps have been in use around the world since 1995. They have found their way
into the world's leading musicians rigs and recording sessions and been featured on thousands
of the best selling (and sounding) albums and live performances.
MINIMUM SIGNAL PATH DESIGN
The U5 includes a variable gain Class A preamplifier to boost low level pickup signals and a high
level speaker input for capturing the live sound of the instruments amplifier. Six passive tone-EQ
curves are also included to enhance a variety of acoustic and electric instruments. A high-cut switch
eliminates unwanted acoustic pickup and high frequency noise, while a  headphone monitor amp
has been included for personal listening. Twin DC coupled Class A output amplifiers drive both low
level microphone preamp inputs and high level +4dB inputs for direct to tape recording or processing.
The active-to-thru switch selects either the instrument input directly or sends the boosted-equalized
signal to the amplifier via the front panel jack. A ground isolation switch eliminates any possible earth
loop or AC buzz problems with complete safety.

U5 SPECIFICATIONS
Circuit Topology:  100% discrete, high-voltage Class A 
Gain:  Switched 3dB steps, maximum gain +30dB 
Input Impedance:  3 ,000,000 ohm unbalanced (single ended) 
Maximum Input Level  +24dBu unbalanced, 400w speaker input 
Output Connectors (2):  XLR type, pin 2 hot electronic balanced 
Maximum Output Level (Class A):  +30dBu DC coupled, balanced 600 ohms (mic and line out) 
Headphone Output:  0.5w into 600 ohms 
Noise 20kHz Unweighted:  -100dBu minimum gain position 
Distortion THD, IMD:  0.1% at +10dB 
Frequency Response, -/+0.5dB:  5Hz to 100kHz 
Frequency Response, -3dB:  1Hz to 500kHz (input band limited) 
High Cut Filter:  -3dB at 8kHz minimum phase design 
Tone Selector:  Six position rotary switch, all passive filters 
AC Power:  Internal toroidal AC supply 
Dimensions:  8.5 x 3.5 x 12 in (216 x 88 x 305mm) 
Weight-Packed:  12lbs (5.4kg) 
Rack mount kit (1) RM-1:  Single U5 19 inch rack mount kit (holds one half rack unit) 
Rack mount kit (2) RM-2:  Dual U5 19 inch rack mount kit (holds two half rack units)