Description
The Useful Arts SFP-30 preamp is one channel of their acclaimed SFP-60 — complete with the exact audio and power circuitry — in a compact tabletop chassis, for less than half the price. Every aspect of the SFP-30 signal path is identical to the SFP-60, except that the SFP-30 lacks a DI input. Other than that, you can now get the great-sounding variable second harmonics of the SFP-60 in a convenient, cost-effective package. As can be found on the SFP-60, the SFP-30 features separate regulated DC power supplies for tube filaments, phantom power, and high voltage. The high-voltage soft-start power supply delivers over 270 volts of clean, regulated power to ensure maximum headroom and the lowest possible noise floor.
Useful Arts SFP-30 Features:
- Each gain stage is single-ended Class A
- Audio Magnetics input and output transformers, plate inductor (custom-wound by CineMag)
- Output transformer with 50% nickel core
- Flat frequency response: 20Hz–30KHz, ±2dB
- Switches: Input selector (rear-panel XLR/front-panel instrument input), highpass filter, input pad, Phase (polarity) Reverse, phantom power, Color knob for variable harmonic distortion
- Switches pass no signal; they control sealed, gold-plated relays for many years of faithful operation
- Input and output levels of the triode stages are separately controllable via detented attenuators; combined with the Color knob, the SFP-30 delivers just over 60dB of usable gain
- New-manufacture JJ EF806 and ECC82 tubes for long life and easy replacement
- Fully modular construction, with gold-plated connectors used throughout audio path
- Gold-plated rear-panel XLR connectors for the transformer-balanced inputs and outputs
- Output level VU meter, op-amp buffered to ensure that the signal is not loaded by the meter
- Audio power supply features toroidal dual-primary transformer and linear regulation for lowest noise
- Voltage selector for 115/230-volt operation
- Faceplate milled from 0.190″-thick aircraft-grade aluminum for maximum rigidity
- Laser-engraved front-panel markings
- Handcrafted in Phoenix, AZ
