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Vincent Audio SP-331MK Hybrid Vacuum Tube Power Amplifier


Step-up model brings Pure Class A sound to a Powerful Premium Hybrid Tube Amp

Vincent Audio has introduced the new SP-331MK hybrid vacuum tube and solid-state power amplifier that is a performance enhanced version of the company’s popular SP-331 power amplifier.

While the Vincent SP-331, like most modern high-performance power amplifiers, operates in Class AB mode across its power spectrum, the SP-331MK operates in pure Class A mode for signals up to 10 watts output, and Class AB up to its full power rating of 150 Watts into 8 ohms and 300 watts into 4 ohms.

When listening to music at moderate sound levels, the power reaching the loudspeakers is typically less than 1 watt, and for serious audiophiles seeking to parse the finest details of a musical performance a pure Class A amplifier is preferred. However, pure Class A amplifiers are quite inefficient, and don’t like to be asked to deliver 100s of watts. With its Class A and Class AB capabilities, the SP-331MK preserves all the accuracy and musical detail at low levels while delivering the sharp dynamic peaks and sustained loud music without running out of steam or clipping.

Vincent Audio SP-331MK Hybrid Vacuum Tube Power Amplifier - Back

The new SP-331MK model builds on the dual 6N16 vacuum tube input stage and powerful solid-state output stages of the base SP-331 model by adding a 12AU7 vacuum tube stabilized Class A power supply. The SP-331MK retains the proven 1000 watt power supply capabilities of the 331 with its massive toroidal transformer and 80,0000 µF per channel storage capacitors. As a result, both amplifiers are among the few that can maintain the full double-the-wattage output in accordance with Ohm’s Law when the speaker impedance is cut from 8 ohms to 4 ohms.

The Vincent SP-331MK has a single pair of high-quality RCA inputs. There are two pairs of speaker binding posts for connection of two pairs of speakers accessed using a front-panel speaker selector switch. The large, rugged 49-pound chassis is heavily damped to prevent microphonics and has side-mounted extruded aluminum heat sinks to control internal temperatures.

The Vincent SP-331MK is currently available in silver or black finish, and it has a suggested retail price of $2,199.95. The original SP-331 continues in the line at $1,299.95.

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Vincent Audio SP-331MK Hybrid Vacuum Tube Power Amplifier - Inside

Vincent Audio SP-331MK Power Amplifier Specifications

  • Frequency Response: 10 Hz – 50 kHz +/- 0.5 dB
  • Nominal Output Power RMS, 8 Ohm: 2x 150W
  • Nominal Output Power RMS, 4 Ohm: 2x 300W
  • Power Output Class A, 8 Ohm: 2x 10W
  • Total harmonic distortion: < 0.1 % (1 kHz, 1 Watt)
  • Input sensitivity: 1,5V * Signal-Noise ratio: > 95 dB
  • Input impedance: 47 kOhm,
  • Inputs: 2 x RCA, Outputs
  • 4 x 2 Speaker Terminal (A & B)
  • Mains supply: 120 V/60 Hz
  • Colors: black or silver
  • Tubes: 2 x 6N16, 1 x 12AU7
  • Weight: 48.5 lbs; 22 kg
  • Dimensions (WxHxD): 17 x 7-3/4 x 15-3/4; 430 x 195 x 400 mm

About Vincent Audio
Vincent Audio manufactures high-end audio components that use vacuum tube and hybrid tube/solid-state technology to produce sound that is powerful, accurate, and texturally satisfying. The brand’s exclusive North American distributor is WS Distributing, LLC, of Grand Rapids, Michigan.

vincent audio sp Reviews

From Critics Around the Web

1 Comment

1 Comment

  1. jack

    August 14, 2013 at 1:07 am

    One heck of an amp! Performance well above its price point which is more expensive than whats listed here… price is $2499

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