The MP566-II is the new improved version of the MP566 with high grade transformers and a new variable high pass filter. It is a dual-triode vacuum tube circuit preamplifier based on a design that was used in several famous devices from the 60's, which has been adapted to the '500' format of API*.

With its fully powered triodes and its two transformers, the MP566-II brings the most fulfilling warmth and color to your Lunchbox.

Highlights

• Dual triode design,
• Input and output transformers,
• High 70dB gain will please the most demanding ribbon mics,
• Variable feedback and output level for total control over tube saturation,
• Continuously variable High-pass filter (12 Hz → 320 Hz),
• Input pad (Low Gain) for hot mics or line levels,
• Full 225 Volts tube supply and full 150mA tube heater,
• 1/4" DI jack, high impedance input for instruments or line signals,
• Sequenced power-up to limit the total inrush current,
• Total iddle current draw less than 150 mA,
• Available assembled or as a full kit (everything included).

Controls

1: PAD Adds a 20dB pad before the input transformer, allowing for very hot mics or line level input.

2: OUT This potentiometer sets the output signal level. In combination with the GAIN knob, it allows you to control the amount of tube saturation you want.

3: Clip LED Green when a signal is present, turns red when getting close to saturation.

4: POLARITY Reverses the polarity (phase) of the output signal when on.

5: GAIN Sets the gain of the tube stage

• For clean gain set GAIN low and OUT high,
• For more tube sound set GAIN high and OUT low,

6: 48V Activate the phantom power for static microphones, the red LED give a visual feedback.

7: HPF High pass filter, continuously variable from 12Hz to 320 Hz.

8: IN Enables the high pass filter.

7: HiZ High impedance Direct Instrument (DI) or line input, connected to the first triode grid.

What's in the kit?

Absolutely everything!

• Passive components (resistors, capacitors, inductors),
• 2 transformers
• Active components (tube, diodes, transistors, LED's, IC's),
• Front panel elements (switches, potentiometers, knobs),
• Connectors, relay,
• PCB's,
• Front panel and side panel,
• All hardware

You bring the solder (use good quality solder, 1mm diameter max) and the Lunchbox.

Difficulty level

The kit difficulty level is average. Nothing difficult but because of the high voltage needed by the tube, it is not recommended to beginners. Good soldering practice is required.

There is no setup. A digital multimeter is needed to test the various voltages.