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The concept behind the Useful Arts SFP-30 Single Channel Tube Microphone Preamp is simple, take the exact audio and power circuitry from the SFP-60, put a single channel into a tabletop format, and make it less than half the price of the SFP-60. Done. Everything about the SFP-30 signal path is identical to the SFP-60, except that the SFP-30 lacks the DI input. Other than that, you can now get the finest, most flexible tube preamp available. A better sonic toolkit for recording simply isn't available at this price. Anywhere.

The Features

High voltage soft start power supply puts out over 270 volts of clean, regulated power to ensure maximum headroom and the lowest noise possible

Each gain stage is single-ended, inherently Class A

Audio Magnetics (Input and Output Transformers, Plate Inductor) custom wound by Cinemag

Output Transformer with 50% nickel core

Frequency response is flat within 2 dB from 20 Hz-30 kHz

Each channel of the SFP-30 features 4 switches: High Pass Filter, Input Pad, Phase Reverse, and Phantom Power

Front panel switches control sealed, gold-plated relays to ensure years of operation without pops and clicks

The input and output levels of the triode stages of the SFP-30 are separately controllable by detented attenuators, and combined with the color control, the SFP-30 provides just over 55 dB of useable gain

Voltage selector for 115/230 volt operation in the IEC fuse block on black panel, gold-plated XLR connectors are on the front panel

The only active devices in the signal path are the three tube gain stages, consisting of 1 EF806 and 1 ECC82 per channel

New-manufacture JJ tubes for long life and easy replacement

Each channel features an output level VU meter, which is op-amp buffered to ensure that the signal is not loaded by the meter

The audio power supply features a toroidal dual-primary transformer and linear regulation for lowest noise


Useful Arts SFP-30 Single Channel Tube Microphone Preamp

  • Useful Arts SFP-30
  • Single Channel Tube Microphone Preamp With Variable Harmonic Distortion
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