SOUND DEVICES MP-1 Portable, battery-powered microphone preamplifier with phantom power

Designed for high-definition field production environments, the studio-quality MP-1 is an ideal line-driver for critical radio, television, and film applications.

The MP-1 is extremely durable and easy to use. With rugged mechanical and electrical construction and high-quality components it will provide years of superb audio performance under the most punishing field conditions.

• Superb audio specifications
• 66 dB of gain, in eleven discrete steps
• Transformer-balanced input and output
• Phantom power - 48 volt or 12 volt
• High pass filter @  80 Hz or 160 Hz, 6 dB/octave
• Limiter makes unit virtually "unclippable“
• High current line output drive
• Excellent immunity to RF interference.
• Battery power (two x AA)
• Durable mechanical construction

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

• 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

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.

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.