VAC Phi 300.1a Amplifier

Click in image above for larger view
Available in black finish above or silver finish below

When State-of-the-Art means exactly this: A cost-no-object amplifier with an aesthetic that positively celebrates the vacuum tube.


“It is critical in manufacturing perfectionist speakers to use related components that reveal all that’s possible; especially in resolution, tonality, dynamics and sound-staging. To this end we’ve evaluated and tried a vast array of the highest end equipment available. VAC’s amplifiers and preamps have turned out to be references of the highest order, and not coincidentally, terrifically enjoyable to listen to
– Alon Wolf, owner Magico Loudspeakers (Magico’s speakers have won numerous top awards here and in Asia in the past few years and range from $22,400 to over $250,000)

Where are the testimonials? Fact is, VAC hand builds each component in such a labor of love, time intensive way and has enough of a diehard following that there is usually a 8-12 week backlog of orders and no units available for review. Nor is there anyway to meet higher demand from a great review. VAC is as non-commercial as it gets and the attention is on making the best gear possible, not the best reviewed gear. So stop on by for a demonstration and compare it yourself to other top flight amps and you’ll understand; the VAC Phi 300.1a Amplifier is truly state-of-the-art, no second guess.

VAC Phi 300.1a Amplifier


VAC Phi 300.1a Amplifier

The VAC Phi 300.1a Amplifier is an extremely potent amplifier guaranteed to transcend your previous ideas of reference amplifiers; majestic, commanding, totally harmonious with astounding definition and holographic imaging. It is based on a direct coupled input & driver circuit that results in the fastest, fullest, most detailed sound that  have ever achieved and you are likely to ever hear. The ambience and retrieval of reverb and decay information is particularly surprising.

Using eight beam power output tubes and a low-mu octal driver, this amplifier possesses an uncanny ability to reveal every nuance in a recording, while preserve the emotion and feel necessary for a truly musical performance. In addition to finesse, it has great power, impact, control, and a low electrical noise floor. This remarkable overall character makes it suitable for use with speakers ranging from high efficiency to the most difficult and demanding.


The VAC Phi 300.1a Amplifier’s eight beam power output tubes yield 300 watts in bridged mono mode or 150 watts/channel in stereo mode at the choice of the user. Front panel level controls may be engaged to aid in balancing biamplified systems. Both balanced XLR and single-ended RCA inputs are provided. Triode operation may be selected at the flick of a switch. The chassis is machined aluminum, with the tubes beautifully showcased behind 0.75″ acrylic glass. Also included are standard 12 volt triggers.

Both single-ended and balanced (fully balanced amplifier mode) inputs are provided. The chassis is custom machined 0.25″ aluminum welded into a solid unitary structure, finished in metallic black paint. The 1″ thick aluminum front panel is finished in hand rubbed silver metallic (or black) lacquer, with bias meter and tube adjustors that make it easy to maintain and optimize. Output matching taps are provided for 2, 4, and 8 ohm speakers.


VAC Phi 300.1a Amplifier
  • 150 watt/channel stereo amplifier
  • 300 watt mono amplifier (bridge mode via switch setting)
  • Bypassable channel level controls (useful for fine tuning biamplification systems or acoustic channel balance)
  • Frequency response 4 Hz to 75 kHz
  • Power bandwidth 13 Hz to 70 kHz
  • Single-ended input via RCA jack, non-inverting
  • Balanced input via XLR jack, non-inverting and fully balanced
  • Hand selected, optimized tubes of 8 x KT88, 4 x 6SN7
  • Triode switch
  • Residual noise typically 0.0007 volts at the speaker terminals
  • 12 volt triggers
  • Illuminated logo; may be switched off
  • Shipping weight 125 lbs
  • Two years parts and labor warranty, excluding tubes.