Picking up on our story of the isolation base shootout at the Munich High-End show of a few years ago,we move back to Boulder Colorado and jump ahead a few years.
In our main listening room everything was powered by a Power Plant Premier sitting on the aforementioned wooden isolation base. I had tried to remove it on several occasions because of space restrictions but every time I did the sound was noticeable deflated and smeared or muddled sounding. Sigh.
At the time we were working hard on designing the new PerfectWave series of Power Plants and moving production from China to Boulder – an undertaking of massive proportions for us and one I would never want to repeat. Working with our mechanical engineer Bill Abplanalp, I wanted to make sure the new Power Plant design took care to address some of the issues I suspected were to blame for the Premier’s sensitivity to microphonics and vibrations. To be honest I was hoping to eliminate the need for the wooden base.
Bill came up with a number of clever additions, using heavier materials, soft density polyurethane mats under the big transformers and a unique heat sink design that would diffuse some of the vibration transmissions picked up by the “singing” heat sink fins and transmitted back into the amplifier components.
Bill’s work was well received and the new designs much less sensitive to being on or off the base but still, I could not live with the new P5 or P10 off the base. That bugged me for the longest time and I began to get the itch to try and solve the problem. At first the new isolation base idea I worked on was just a passing hobby but later it got more interesting and began to form as a real project that used engineering resources.
Understanding that I needed a combination of mass and diffused contact with the resonating surface the base would sit on, I started out with a huge 1/4″ thick plate of raw steel that weighed about 15 pounds or so. I mounted a set of rubber feet below the plate and set the Premier on top of it. Interesting results. There was a definite improvement but not as good as the wooden base.
Tomorrow the new base takes shape.
Paul McGowan – PS Audio, Intl.