Content |
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 .
|
Having had great success with the PRE-73 preamp, we have received many requests for a version for the 500 eries rack format. We are therefore happy to present the PRE-573, expected to start shipping in late September.
The PRE-573 is a one width module that has the sound and the features that made the PRE-73 so successful and a few additional ones.
The circuit still uses the preamp and output section from the classic 1073-module, adapted to work in the api rack format. It has a total gain range from -15 to +80 dB. The 10 - 70 dB range is handled by a turn switch and there is a separate toggle switch to select an additional 5 or 10 dB gain. The input can be configured to accept line level signals by another switch, the gain is then lowered by about 25 dB and the input impedance increased to about 15 kohm.
The input impedance of the mic input mode can be switched between 1200 and 300 ohm. Phantom power and phase reverse is also selectable by front panel switches.
An added feature, using the same circuit as in the PRE-73 DLX, is the active DI-input with a high input impedance of about 1,5 Mohm. The output signal from the active DI circuit passes through the input transformer for some extra character.
The DI-input is very flexible since it can be changed to a purely passive one by a front panel switch. The DI input is then exactly the same as in the PRE-73 Mk2 where the signal is feed directly into the second gain stage, bypassing the transformer and with an input impedance of about 100 kohm.
These two DI-options makes it possible to get different tones from electric instruments and the passive DI input mode is more suited for injecting active units like sound modules.
A new feature is the switchable AIR mode that adds a small boost above 10 kHz that peaks at 2 dB at about 35 kHz.
A simple but effective signal and overload indicator is offered by a single LED that starts glowing red at about +4 dBu and then increases its intensity up to the maximum output level.
The PRE-573 has a dedicated insert connector at the back allowing it to interface with other GAP 500 modules. The insert can be activated by removing a jumper connector at the back of the module.
The second Golden Age Project module for the api 500 rack will be the EQ-573, expected to ship in November 2012. The EQ-573 consists of the inductor based high pass filter section and the 3-band eq section from the classic 1073 module with some added frequencies. These two modules together will offer a fully fledged 1073-module in a compact format at a very low cost.
There is a second jumper at the back of the module that selects 600 ohm termination on the output. The standard mode is termination on, since it gives the flattest response when the PRE-573 is used with modern line inputs that typically has an input impedance of 10 kohm or more. The user can chose to remove the jumper and deactivate the termination resistor, this will increase the level above 10 kHz and create a peak in the response for an even more pronounced "Air" effect.
The output is transformer balanced and fully floating and can drive a 600 ohm load up to level of about 28 dBu.
|
- 1 microphone, XLR (bal.) or 6.3 mm jack (unbal.)
- Gain control, 10 steps (6-50 dB)
- Phantom power can be switched on
- Clip LED
- 1 line output, XLR (bal.) or 6.3 mm (unbal.)
- Operation via supplied power unit
Power supply: | 12 V DC, 150 mA | Input impedance: | 10 kohms bal./unbal. | Max. input level: | +4 dB bal./+10 dB unbal. | Gain: | 50 dB XLR/44 dB jack | T.H.D.: | 0.01 % | Frequency range: | 25 Hz - 16 kHz | S/N ratio: | >75 dB | Dimensions: | 143 x 93 x 45 mm | Weight: | 350 g |
|
Two channel classic Focusrite ISA transformer-based preamps Front panel, per channel: - 1/4" instrument input
- Variable input impedance - Low, ISA 110, Medium, High
- Input selection - Mic, Line, Instrument
- 0 - 30 dB/30 - 60 dB gain switch
- Phantom power switch
- Phase invert switch
- 0 - 60 dB gain in 10 dB steps
- 0 - +20 dB continuously variable trim
- Variable high-pass filter with on/off switch
- Insert point on/off switch
- Eight-LED user-calibrated level meters
- Single power switch
Rear panel, per channel: - XLR-F mic inputs
- 1/4" TRS line inputs
- 1/4" TRS Sends
- 1/4" TRS Returns
- XLR-M line output
- Single peak meter calibration dial
- Single IEC power socket
Measured Performance Maximum Input and Output Levels | Maximum Output Level |
+24 dBu with a THD+N
| Maximum Microphone Transformer Input Level | +7 dBu with a THD+N | Mic Input Response | Gain range | 0 dB to +60 dB in 10 dB steps, plus 0 dB to +20 dB continuously variable trim |
Input Impedance
| Switched Impedance setting
Equivalent Input Impedance at 1 kHz | Low = 600 Ω
ISA 110 = 1.4 kΩ
Med = 2.4 kΩ
High = 6.8 kΩ | EIN
(Equivalent Input Noise) | Measured at 60 dB of gain with 150 Ω
source impedance and 22 Hz-22 kHz band pass filter | -127 dB |
Noise
| Noise at output with unity gain (0 dB) and 22 Hz-22 kHz band pass filter | -97 dBu |
Signal-to-Noise Ratio
| Measured with 150 Ω source impedance and 22 Hz-22 kHz band pass filter | 121 dB relative to max output +24 dBu |
Total Harmonic Distortion + Noise
| Measured with a -20 dBu input signal at +30 dB of gain and with a 22 Hz-22 kHz band pass filter |
|
Frequency Response
| At minimum gain (0 dB) |
-0.5 dB at 10 Hz,
-1 dB at 135 kHz, relative to 1 kHz
|
At +60 dB gain
| -6 dB at 10 Hz,
-1 dB at 115 kHz, relative to 1 kHz |
CMRR (Common Mode Rejection Ratio)
| -94 dB for mic input at 60 Hz for max. output = +24 dBu
-91 dB for mic input at 10 kHz for max. output = +24 dBu |
Crosstalk Channel to Channel
| Mic input, with I/P = 0 dBu, gain = 0 dB @ 1 kHz input to channel A, channel B output = -85 dB | Line Input Response |
Gain Range
| -20 dB to +10 dB in 10 dB steps, plus 0 dB to +20 dB continuously variable trim |
Input Impedance
| 10 kΩ from 10 Hz to 200 kHz |
Noise
| Noise at main output with gain at unity (0 dB) measured with 50 Ω source impedance and a 22Hz - 22 kHz band pass filter |
-97 dBu
|
Signal-to-Noise Ratio
| Measured with 50 Ω source impedance and a 22 Hz-22 kHz band pass filter |
121 dB relative to max output +24 dBu
|
Total Harmonic Distortion + Noise
| Measured with a 0 dBu input signal, +10 dB of gain and a 22 Hz-22 kHz band pass filter |
|
Frequency Response
| At unity gain (0 dB) | -0.3 dB at 10 Hz,
-1 dB at 80 kHz, relative to 1 kHz |
Crosstalk Channel to Channel
| Line input, with I/P = 0 dBu, gain = 0dB
@ 1 kHz input to channel A |
Channel B output
= -91 dB
| Instrument Input Response |
Gain Range
| +10 dB to +40 dB continuously variable trim |
Input Impedance
| > 2 MΩ |
Noise
| >Measured with 22 Hz-22 kHz band pass filter | Minimum gain (+10 dB) = -95 dBu |
Frequency Response
| At minimum gain (+10 dB) |
-0.1 dB at 10 Hz,
-1 dB at 115 kHz, relative to 1 kHz
|
At maximum gain (+40 dB)
|
-2.5 dB at 10 Hz,
-1 dB at 110 kHz, relative to 1 kHz
| High-Pass Filter |
Roll-Off
| 18 dB per octave (3 pole filter) |
Frequency Range
| Continuously variable from 16 Hz to 420 Hz (-3 dB) | Weight and Dimensions |
W x D x H
| 480 mm x 280 mm x 44 mm |
Weight
| 3.7 kg |
|
Mic Inputs
• Frequency response at minimum gain (0dB): -0.35dB at 20Hz and –3dB at 122kHz
• Frequency response at maximum gain (60dB): –2.5dB at 20Hz and –3dB 103kHz
• Gain range: 0dB to +60dB in 10dB steps, plus 0dB to +20dB continuously variable trim
• Maximum headroom: +7.4dBu
• THD+N: 0.0009% (measured at 1kHz -20dBu input signal, at 30dB gain setting, with a 20Hz/22kHz bandpass filter)
• Noise EIN: -126dB (measured at 60dB of gain with 150Ω termination and 20Hz/22kHz bandpass filter)
• Noise at main output with unity gain: -98dBu (measured with a 20Hz/22kHz bandpass filter)
• SNR: 123dB (relative to max output 25dBu)
• SNR: 120dB (relative to 0dBFS (+22dBu)
• CMRR: 88dB.
• Input Impedance, variable: 600Ω, 1400Ω, 2400Ω, 6800Ω
Line Inputs
• Frequency Response at unity gain (0dB): -0.3dB at 20Hz and –3dB at 94kHz
• Gain range: -20dB to +10dB in 10dB steps, plus 0dB to +20dB continuously variable trim
• Maximum headroom: +25.4dBu
• THD+N: 0.002% (measured with +4dBu input signal, 0dB gain setting, with a 20Hz/22kHz bandpass filter)
• Noise at main output with unity gain: -91dBu (measured with a 20Hz/22kHz bandpass filter)
• SNR: 116dB (relative to max output 25dBu)
• SNR: 113dB (relative to 0dBFS +22dBu). Input Impedance: 10kΩ
Instrument Inputs
• Frequency Response at +10dB gain: -0.2dB at 20Hz and 0dB at 200kHz
• Frequency Response at +40dB gain: -3dB at 20Hz and –3dB at 38.4kHz
• Gain range: +10dB to +40dB continuously variable
• Maximum headroom: +11.5dBu
• THD+N: 0.006% (measured with –20dBu input signal, at minimum gain (+10dB), with a 20Hz/22kHz bandpass filter)
• Noise at main output with minimum gain (+10dB): -95dBu (measured with a 20Hz/22kHz bandpass filter)
• Input Impedance = >1MΩ
High Pass Filter
• Roll off = 18dB per octave 3 pole filter
• Frequency range: 16Hz to 420Hz (continuously variable, measured at the 3dB down point)
Meters
• 6 LED meter is calibrated 0dBFS = +22dBu (the maximum level which can be correctly converted by the optional internal A/D converter before overload occurs). The meter calibration points are as follows:
Meter panel calibration value in dBFS / Equivalent dBu value
0dBFS / +22dBu
-2dBFS / +20dBu
-6dBFS / +16dBu
-12dBFS / +10dBu
-18dBFS / +4dBu
-42dBFS / -20dBu
Front and rear connectivity
Analogue Channel Inputs (Inputs 1-4)
• 4 instrument 1⁄4” TS jack inputs on front panel
• 4 microphone XLR inputs on rear panel
• 4 line 1⁄4” TRS jacks on rear panel
• 4 insert return 1⁄4” TRS jacks on rear panel
• 4 ADC XLR inputs on rear panel
Analogue Audio Outputs (Outputs 1-4)
• 4 line XLR outputs on rear panel
• 4 insert send 1⁄4” TRS jacks on rear panel
Other I/O
• IEC power input connector 100Vac – 240Vac
Front Panel Indicators
• 8 output meters, 6 segment
• 4 30-60 mic gain range selection indicator
• 4 +48V phantom power indicator
• 4 Phase indicator
• 4 Insert In indicator
• 4 Filter In indicator
• 4 Input selection indicators (Mic, Line, Inst)
• 4 Z In microphone input impedance selection indicators (Low, ISA110, Med, High) Clock select indicators (44.1, 48, 88.2, 96, 176.4, 192)
• Ext clock indicators (Lock, Word clock, 256X)
Weight
5.5kg
12.2lbs
Dimensions (W x H x D)
480mm (W) x 88mm (H) x 280mm (D)
19" (W) x 3.5" (H) x 11" (D)
|
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 |
Reviews
There are no reviews yet.