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Two months after I published the following article, a reader pointed out that an individual under the handle Banpuku operates this website where he sells Vacuum State products. His equipment listing on Audio Asylum mirrors the below system to perfection. Reviewing products one sells under a different name would be shamefully deceptive if both occurred during the same time. While Allen Wright of Vacuum State confirmed that Pat Kennedy is Banpuku but became a dealer only after submitting this review, I felt it prudent to make this announcement - Ed.

Pat Kennedy
Vinyl source: Transfiguration Orpheus MC cartridge, Schroeder Reference arm, Brinkmann Balanced deck, HRS
Designs MRX platform
Preamp: Vacuum State RTP3D with built-in MC phono stage
Power amps: Vitus SM-101 monoblocks
Loudspeakers: Marten Design Coltrane
Cables: JPS Labs Aluminata, Fusion power cords
Review Component Retail: $

Allen Wright is the owner and designer of Vacuum State GmbH of Switzerland. In addition to his noted upgrades to SACD players, Allen is a highly regarded designer of preamplifiers and amplifiers. There are no secrets. Allen publishes a cookbook with design details which enables DIY enthusiast to build state-of-the-art audio components based on his designs. I became interested primarily because of Allen’s work on turntable/cartridge setup and his position on recorded absolute polarity. 

Allen maintains that correct absolute polarity is fundamental to music reproduction. Without it, recordings are robbed of their full potential. To this end, I started fussing with absolute polarity and discovered that Allen’s position was spot on. In the wrong polarity, recorded music appears confused, thin and dead. With it, it becomes more life-like. In Allen, I found a kindred spirit who valued proper turntable/cartridge setup and absolute polarity. We started conversing and I ultimately discovered his Vacuum State RTP3D preamplifier.

Over the past 10 years, I have owned or had in my system for audition 11 high-end preamplifiers. While all were high ticket items ranging from $8,000 to $50,000, build quality varied materially and in some cases was not commensurate with the price (I am very demanding). The RTP3D retails for $24,900. This created high expectations for build quality. I was neither disappointed nor completely enamored. The point-to-point wiring is executed with precision and care. Electronic parts are of the highest pedigree. Attention to detail is clearly evident when looking inside both the power supply and main unit. The layout of the back panel is logical and gives ample space between sockets. The front panel has four knobs and one mute switch. The notched knobs turn with precision and ease. No complaints there.

Prior to receipt, I’d asked Allen about his thoughts on vibration damping. He felt that it is system dependent. What works well in one system won’t in another. To this end, Allen does not overdamp the RTP3D. If I had my druthers, I’d like to see thicker aluminum chassis panels. The front is appropriately thick but the top, bottom and sides could be much thicker - or at a minimum, be damped in some fashion. I’d give an A for smooth exterior finish, the execution of the point to point wiring and soldering, the elegant clean aesthetics, the channel-specific absolute polarity function and the overall simplicity. I’d give a C for the lack of vibration damping and the ringy top and bottom panels which should be addressed. Overall this is a very well-made unit especially considering that it is a tube preamplifier.

The RTP3D arrived in a heavy cardboard box. Inside both the power supply and main unit were encased in a foam structure that allowed easy access while being protective. Allen agrees that going forward, both units will additionally be wrapped in a protective cloth. All in all, the RTP3D packing is solid and functional.

High-end preamplifier functionality varies widely. I prefer the keep it simple stupid approach which at least theoretically minimizes parts and electrical connection points. The RTP3D is certainly a KISS product with only two features to elevate it above a baseline bare-boned product. First, it has a mute switch, in my opinion a must for any preamplifier. Second, the RTP3D has channel-specific absolute polarity switches. It’s the only one I know of which does. This is a huge advantage. If your system is resolving enough and your ears tuned/sensitive to polarity variances, it allows for maximum musical enjoyment.

When asked how a system or component sounds, I typically start by describing tonality based on scale from 1 to 10. 1 is super tubey, warm, mushy and caramelized. 10 is etchy, hyper resolving, ear-pinching transistor sound. This subjective scale represents a spectrum where a score of 1 is no better than 10 or or vice versa. If you have heard enough, you know the culprits at either ends of this spectrum. My personal preference is for a tonal balance of 4.5 to 5.5 which combines the best of tubes and transistors. Based on my experience, only two other preamps had their tonality in my preferred range - the Lyra Connoisseur 4.2L & P SE (5) and the Vitus SL-010 (5.5). Either of these transistor units had wonderful resolution, bandwidth and enough body and warmth to distance themselves from typical solid-state sonics. However, I always wanted a bit more warmth and body without sacrificing other transistor benefits. Enter the RTP3D with a spot-on tonal balance between 4.5 and 5. It has just enough bass and midrange fullness to sound like live music. While tube based, it is not tube sounding. True, the midrange is wonderful and life-like but not bloated or colored like other valve units. The frequency extremes are not compromised. At 10kHz and above, the RTP3D in fact is more extended than any preamp I have heard to date. This is probably due to its ultra-wide bandwidth out to a reported 2MHz.