SW1X PRE IV

6V6 Valve Phono Pre-Amplifier

Featuring a signal output transformer (OPT) de-coupled 6V6 tube output stage and an uncompromising zero negative feedback (NFB) approach (Zero NFB global or local) the PRE IV delivers an uncoloured, pure musical experience like no other.

Unlike traditional power amplifiers, the PRE IV is meticulously engineered to preserve signal integrity while achieving exceptionally low output impedance. With an output impedance below 10 Ohms, it offers the sonic finesse of directly heated triodes (DHT) combined with a commanding drive capability, effortlessly powering any amplifier.

The sound is mature, large & holographic with scale, authority and dynamic range but above everything very transparent comparable to a great passive volume control. It is a great enhancement to any tube power amplifier, driving a source (DAC or Phono), which has a weaker small signal, indirectly heated tube based output stage.

SW1X Audio Design™ PRE IV Line Pre-Amplifier Features:

• Specially selected and harmonically matched component & material quality
• Performance Level 4
• Copper or Silver wound Super HiB DC-core Signal Output Transformers
• Zero NFB, 2 x 6J5 driver tubes and 2 x 6V6 Power Output Valve Output Stage
• 5Z3/5U4G/274B or 80 Directly Heated double diode tube rectified C2xLC (choke filtered) power supply
• Internally wired exclusively with our SW1X Magnum, Genesis and Opus Copper or Silver (on request) conductors
• Vintage, out of production AB 2W & 1W resistors
• Dual Mono Stepped attenuators with AB carbon resistors and AN 2W Niobium or non magnetic Copper Tantalum at input
• XLR Balanced and RCA Single Ended outputs

Versions

PRE IV is available with following output transformer (OPTs) specifications:

• Standard : SW1X Audio Design all Copper wound, orient grain M6 EI Core OPTs
• Special :  SW1X Audio Designall Copper wound Super HiB DC Core OPTs
• Classic : SW1X Audio DesignCopper/Silver Windings, Super HiB DC Core OPTs
• Signature : SW1X Audio DesignSilver/Silver Windings, Super HiB DC Core OPTs

Tube Compliment

2 x 6J5

2 x 6V6

1 x 5Z3/5U4

Optional Extras:

• Fully Hardwired Tube Output Stage on the Bakelite Board
• Fine Silver wiring on the Input, Bakelite Board and Output
• SHiB double DC-Core mains transformers and chokes
• Silver Foil capacitors Inter-stage Signal de-coupling Capacitors

Note: Due to SW1X Audio Design’s ongoing research and development process, specifications are subject to change without notice