Super Pas 4i SL Buffered Vacuum Tube Preamplifier

Price: Circuits: Super Pas 4i Chassis: SL Options: International Transformer

This economical extension to our Super Pas 3i SL retains all of its musical liquidity, image, and space while adding the load driving capability, range extension, detail, bass reach, and impact of our solid state designs. It is available as a complete kit or factory wired.

It features complete buffered vacuum tube line and phono circuits that drive real world loads and operate at very low distortion, wide bandwidth, and astonishing transparency.

The vacuum tube stages provide all of the voltage amplification but do not have to look at any real world loads. The current buffers provide a very low output impedance with very high output current to effortlessly drive long cables and low input impedance amplifiers. The buffers unload the vacuum tubes, dramatically increasing the open loop gain of the vacuum tube stages. This significantly reduces the already low distortion, improves high and low frequency linearity, and makes the preamp better than ever.

The Super Pas 4i SL features precision stepped volume and balance controls and a silver contact fiberglass selector switch. It has a mono-stereo switch, a tape monitor switch, a tape 1 - tape 2 switch, and a lighted power switch on the front panel. It has 20 input and output gold plated jacks handling phono, CD, FM, spare (for VCR or TV), two sets of tape in, two sets of tape out, and two sets of audio outputs. It has three convenience AC outlets. Unique to vacuum tube preamplifiers, the Super Pas 4i SL features an exquisite headphone amplifier built in at no extra cost.

A shielded toroid power transformer is standard. A 50 Hz/60 Hz 120V/240V international toroid transformer is available as an extra cost option.

The Super Pas 4i SL has great musicality and is fun and easy to build. See the reviews in the August, 1993 issue of Audio magazine and the Fall, 1993 issue of The $ensible Sound.

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