Model 01 Preamplifier

Design spec

Inspiration

Detail

The design is simple and uncluttered, with a minimum of controls and features but with microcontroller function over input selection and power control. Pressing the selection dial powers the unit on and off, presence of a lit source LED providing visual power on confirmation.

Front view

Construction and layout

In system

The design is intended to be budget priced, with an emphasis on ease of manufacture and build. All electronics are assembled on a single PCB, held in slots already machined into the enclosure's sides; no extra fixings are required. The PCB is mounted upside down to allow both the LEDs and control dials to be mounted directly to it; in the case of the LEDs, they are soldered directly to pads on the front edge of the PCB.

Although designed to be relative low cost, the design follows the path of cutting cost by removing unnecessary features; emphasis is still placed on sound quality, using a high quality volume control and similar line level circuitry to the rest of the range. Input selection and power control is via rotary encoder dial, audio inputs being FET switched for compactness and simplicity. No mute function is provided, simply as it would require an extra indicator LED, adding clutter to the front panel.