The VAC Statement 450: the redefinition of World Class
For several years the VAC Phi 300 amplifier has been earning a reputation among perfectionists as of one the finest power amplifiers available, routinely matched with speakers in the quarter million dollar class. Lately we've been wondering, what would happen if we were to remove all of the constraints and design an amplifier without any regard to cost, without any regard to size, and without any regard to weight?
The answer is the VAC Statement 450.
The sound of the Statement 450 literally caused our jaws to drop. If the Phi 300 is one of the world's best amplifiers, then the Statement 440 is no less than the redefinition of the term "World Class". It is not a subtle improvement. It is a whole new world.
VAC President Kevin Hayes describes its sound as follows: "This is an absolutely startling jump in sound quality. The voices, images, and dynamics are as solid as a concrete wall, and there is an order of magnitude more detail being presented, which manifests not only in hi-fi terms, but in emotion and, for example, being able to picture the expressions that play across a singer's face. It's not a subtle difference, or even a moderate difference; it is a quantum jump."
VAC's "first principles" design approach led us to four critical factors in the design and voicing of the Statement 450: increased precision of control over the drive/output circuit; control over stray interactions within the amplifier; architectural control of mechanical resonances; and avoidance of electrically large, slow components. The result is, predictably, a design completely unique to VAC.
The Very Low Impedance Driver (VLID) circuit gains much greater control over the transfer function achieved in the output stage, improving linearity and increasing headroom. There is palpably more control, greater subjective power per watt, and increased detail.
The potential benefit of hand wiring is that the designer gains infinitely more freedom in "voicing" through the ability to select the brand, conductor material(s), insulation, size, and geometry of wires used to build the amplifier. This has been exploited in many previous VAC designs. However, the approach presented in the Statement 450 far exceeds conventional hand wiring and previous three dimensional techniques. Careful architecture and orientation of parts in 3D allows passive control of radiated fields to an unprecedented degree for an audio amplifier. Special consideration of they ways in which they interact with the chassis, sensitive circuit points, and each other increases purity and resolution.
Modularization of circuit assemblies, particularly the Modular Output Tube Assembly (MOTA), allows the mechanical properties of the stages to be independently controlled and optimized. Parasitic mechanical constraints of critical capacitors is essentially eliminated. The lengths of many critical leads and connections can be controlled and minimized. All of this yields greater precision and increases both the solidness and the subtlety of dynamics and transients.
While the MOTA techniques improve how the audio circuit deals with mechanical energy input, the overall architecture of the amplifier chassis and separate power supply minimizes the presentation of external vibration. We start with 0.25" aircraft aluminum for a rigid basis, and tailor the mounting points and couplings for the desired result. Between the two chassis, 105 lbs. of custom magnetic transformers contribute to the corresponding optimal mass loading. Custom machined feet provide a slight, controlled decoupling of the power supply from the external environment, while the audio chassis connects via a tripod of custom designed stainless steel cups and balls, controlling of the flow of vertical energy inputs and dissipating lateral energy inputs. The proprietary VAC design provides a gentle yet powerful docking and, unlike prior art, is not prone to dangerous instability.
With 440 watts RMS continuous output power (880 watts instantaneous peak power) per monoblock, there is a great sense of freedom and ease, even with difficult loads and demanding massed passages. This is due in part to a ‘divide and conquer' electrical architecture that is in stark contrast to the single massive tube approach sometimes seen in other amplifiers; those designs feature a ponderous single tube with high stray capacitance, very high operating voltage, and a corresponding degradation in output transformer coupling due to high impedance and high insulation requirements. In addition, the magnetic circuits of such amplifiers have high inertia and can not track and convey a musical waveform with the faithfulness we require. VAC's Very High Speed Parallel (VHSP) technique uses fast, lithe devices in an analogue parallel processing configuration that allows the speed and control required to preserve delicacy and natural sound. Key elements include specially designed US made output transformers with an astonishing 750 kHz bandwidth, an extraordinary new implementation of the legendary KT88 beam power tube, and an extended range of Class A1 operation. Here is power and speed that preserves the nuance and expressiveness of the "first watt".
The external power supply also uses custom transformers, wound in the USA; there are no lightweight off-the-shelf magnetics here. The three massive transformers, which power seven separate basic supplies, are isolation mounted in a separate shielded segment of the power supply chassis and potted in place with a special material to ensure low mechanical noise and vibration. Proprietary techniques give the bridge rectifiers the low noise associated with vacuum tube rectifiers, but deliver the speed and high passive regulation inherent in silicon diodes. Active voltage stabilization is used where appropriate. VHSP is used in the filter banks, greatly extending the bandwidths of the critical power sources. Six additional filter banks are located in the audio chassis, directly at the points of use, for more than 400 joules of energy reserve.
Balanced (Neutrik) and single-ended (Cardas rhodium) inputs are provided, as are output connections (Cardas rhodium) to precisely match loudspeaker loads of 2, 4, and 8 ohms. Everything you need to monitor and optimize operation is at your fingertips (no voltmeters required). Of course, the internal parts are the finest kind, specifically chosen for sound and reliability. The finish is high gloss hand polished black or silver with glass. And, naturally, the Statement 450 is entirely handcrafted by VAC in the United States of America.
If you are ready for unmatched performance and excellence, if you are ready for the highest sonic performance in the world, then you are ready for the VAC Statement 450.
We build the world's finest audio components TM
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