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The PRE-73 DLX is a one-channel vintage style microphone-, line- and instrument preamplifier. The signal path uses only discrete components like resistors, capacitors and transistors. The line and microphone input and the line output are transformer balanced, using three different transformers, each one optimized for its purpose.
This is the way audio components were built before integrated circuits became available. The subjective sound quality delivered by vintage equipment is often prefered over the one delivered by modern units, a situation that is even more obvious now when music is recorded with clean-sounding digital audio equipment.
The circuit used in the PRE-73 DLX 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 on the mic input is 80 dB, enough to handle passive ribbon mics with quiet sound sources.
- Gain range on the Line input: -20 to + 10 dB.
- Switchable impedance on the mic input, 1200 or 300 Ohms, will change the tone of most mics.
- 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 controls 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 jacks and separate output XLR and TRS jacks for flexible connections.
- Insert jack for inserting EQ´s and other units.
- External high power power supply to avoid interaction with the audio circuits and transformers.
- A solid build quality that will last many years of normal use.
The PRE-73 DLX has a number of improvement and new features compared to the PRE-73 MKII:
- Tantalum capacitors in the signal path.
- Selectable 1073-style high pass filter, 50Hz, 80Hz, 160Hz and 300Hz.
- Output Attenuator -7, -14, -21 and -28 dB (located after the output transformer) allows overdriving the output stage and the output transformer for added character by lowering the output signal to a suitable level.
- The circuit board is prepared for Carnhill Mic and Line transformer and high pass inductor.
- The Insert jack can be switched in/out from the front panel. An internal jumper can select that the Insert jack always has an output signal.
- Switchable 600 ohm Output Termination and Ground Lift on the back panel.
- Selectable Active or Passive DI input and selectable input impedance in active mode, Hi Z or 100 kohm, by internal jumpers.
- The DI can signal can be selected to pass or bypass the mic input transformer by internal jumpers.
- Relays are used to control internal switching for DI input, Phantom power, Mic Low Z, Insert and Phase for shorter circuit board signal paths. The relays are controlled by front panel switches.
- Revised gain switch for added headroom.
- Circuit board star grounding scheme.
- Revised power supply with separate regulators for the audio circuits and relay and LED circuits.
| Highly versatile and portable, Sound Devices' MM-1 is a single-channel, portable microphone preamplifier with a powerful headphone monitoring function. Proven in mission-critical applications, the high-performance microphone preamplifier uses a transformer-balanced input and output with a bipolar ±15 volt power supply to produce low-noise, low-distortion gain at all switch positions. It features an "unclippable" dual-stage limiter and two-position high-pass filter. Flexible microphone powering provides phantom power at 48 volts or 12 volts and 12-volt T-power. It is powered from two-AA batteries or external 5-18 VDC.
The MM-1 is at home in high-definition television production, corporate/industrial environments, radio/television announce booths, and music production. Its headphone monitor is an advantage in applications where communications channels or mix-minus feeds need to be monitored in headphones. The user can monitor both microphone audio and external audio sources in headphones with level control.
The MM-1 is designed to be durable. Its aluminum chassis, oversized end panels, machined knobs, and panel mounted connectors assure reliable mechanical operation.
- Maximum of 66 dB of gain, in eleven discrete steps
- Dynamic range exceeding 120 dB
- 10 Hz to 50 kHz audio bandwidth
- High immunity to RF interference
- High current line output driver
- Transformer-balanced input and output
- Extended range peak limiter via dual opto-isolators makes preamplifier virtually "unclippable“
- Selectable 48-volt / 12-volt phantom power or 12-volt "T" power
- High-pass filter @ 80 or 160 Hz, 6 dB per octave
- Headphone monitoring of microphone audio, monitor audio, or a mix of both
- Monitor input accepts mono, balanced or unbalanced line-level inputs on 1/4-inch tip-ring-sleeve connector
- Separate level control of Monitor gain and overall headphone gain
- Split ear function via DIP switches
- Internal battery power (two-AA)
- Excellent battery life with alkaline and NiMH rechargeable batteries
- External 5-17 VDC powering (plug included)
- High-strength aluminum chassis with durable belt clip
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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 |
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Frequency Response
| At minimum gain (0 dB) |
-0.5 dB at 10 Hz,
-1 dB at 135 kHz, relative to 1 kHz
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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
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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
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Total Harmonic Distortion + Noise
| Measured with a 0 dBu input signal, +10 dB of gain and a 22 Hz-22 kHz band pass filter |
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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
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At maximum gain (+40 dB)
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-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 |
| Vacuum Tube Mic Preamp. 12AX7 Vacuum Tube. +48V Phantom Power, 20dB Pad.
This premium tube mic/line preamp features an integrated limiter for studio,
live and hard disk recording applications. It features a carefully-selected
12AX7 vacuum tube with Behringer's UTC technology for exceptional warmth
and lowest noise. Using the MIC100 is a great way to eliminate the "dull"
sound of standard digital recorders & sound cards. Also, it perfectly
complements studio-grade condenser mics. When used as a high-end DI-box,
it ensures outstanding signal integrity. Features also include a phase reverse
switch, +48 V phantom power, a 20 dB pad, and balanced I/O.
The heart of the Tube Untragain is an extremely low-noise microphone preamp
circuitry that uses discrete components and produces a highly trans-parent
sound. In combination with Behringer's tube technology, the operational amplifiers
4580 and a sophisticated circuit topology, the Tube Untragain yields excellent
noise and distortion properties. The innovative UTC circuitry that has been developed
by our engineering team offers an abundance of sound-shaping possibilities.
Absolute musicality was Behringer's major goal when we designed the Tube
Untragain. The result is a device that, thanks to our tube circuitry, lends an
incredible punch to percussion instruments. On the other hand, instruments
that are rich in upper harmonics will receive more transparency. The sound
will be warm, detailed and brilliant.
Technical Description
Specifications
XLR input Connector: Balanced/unbalanced
Type: Transformerless, DC-decoupled input
Impedance: Approx. 2 kOhms
Maximum input level: +7 dBu / 20 dB with pad
1/4 in. TRS input Connector: Balanced/unbalanced
Type: Transformerless, DC-decoupled input
Impedance: Approx. 1 MOhms
Maximum input level: +16 dBu / 20 dB with pad
Audio outputs Connectors: XLR and 1/4 in. TRS connector balanced/unbalanced
Type: Transformerless, DC-decoupled output
Impedance:
Approx. 700 Ohms balanced
Approx. 350 Ohms unbalanced
Maximum output level: Approx. +26 dBu @ 100 k§?
System Frequency Response Mic input: |
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
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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.
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