Hello fellow Audiolics, welcome to another meeting of Audiolics Anonymous, our support group for the insatiably TWEAKED. As you may remember from the last column, the month was a disaster for tweaking at the Gaw listening room. Just about everything that could go wrong, did. Going from one problem to the next reminded me of some Blond Jokes Iíve heard. But I must say, this monthís tweaking has gone superbly, and I think I now have the best sound I can remember from my system. I also had Clark Johnsen and a friend of his from Japan over for a session last Sunday, and he agreed that the system did indeed sound the best ever. So for a change, I am satisfied with it. Of course just for now. All of the interconnects have been repaired, and I have found a new method of building the Alan Wright Silver Foil interconnects, www.VacuumState.com, which is easier, with much less risk of breakage, cheaper, and sounds just about the same. More on this later.
The main topic of this monthís meeting is the single biggest improvement I have made in my system in months: of all things, an equipment rack.
Airhead Suspense Equipment Rack .
Basically, the better the equipment, the more structural and air vibration transmitted to your components will affect the sound, blurring images, distorting the sound stage, and loosening the transients. And believe me, mechanical vibration distortion is a hundred times greater than any electrical, especially with turntables and transports. One can damp the cabinets with mass, gels, paints, etc., or try to ground the vibrations with feet, but isolating them from the noise in the first place, works best. Enter the above two products, with the VIBRAPLANE being discussed in the previous article.
The Airheadis the top portion of the unit which does the suspending. It was originally developed as a single shelf platform for turntables back in the early nineties. I can still remember first seeing it set up at a CES back then. It is a hollow box with three inner tubes inside with a metal plate- Acrylic top suspended by the tires, and still sells for $315, a true bargain. Ray found the the Airhead could suspend the heaviest turntables with ease, and came up with the bright idea of attaching it to four legs, and adding multiple shelves below it. Thus was born the rack.
The unit is a 24Ē deep x 24Ēwide rack, which can be supplied in heights up to 48 inches, and comes with four 3/4 inch thick clear acrylic shelves suspended by four rods to an isolated top made of a massive steel plate with a smoky black acrylic top and base. The shelves and top plate are isolated from the stand and environment by three inner tubes under the top. The fifth shelf on the bottom is unisolated and fine for storage. The stand looks great, is well constructed, and does exactly as specified, i.e., isolate all of the equipment from structural vibrations down to the single Hertz level, and the thick acrylic shelves will ground the airborne vibrations if appropriate feet are used. The shelves are extra large, and will accommodate the largest pieces of equipment, and in most cases two to three per shelf. The top is the perfect place to set up your turntable or digital transport, and Ray has said that the unit will take a maximum of 600 lb.., so I doubt you can overload it. I have my 275 lb. Walker Proscenium on top, my two preamps next, then my DVD-CD transport, signal processors and Crown Macro Reference Amp, and the unit could still hold plenty more equipment. One can special order by height, shelf color, at, of course, a special price.
It came in three fairly heavy boxes, well packed, and no damage was found. The setup instructions, while adequate, could use some improving, especially since they make no suggestions for tweaking, and leveling and truing up the platform before placing the equipment. Construction time was about 1 1/2 hours, with only a wrench, screwdriver, and an included Allen Wrench and level needed. The included Speed Nuts for shelf suspension made placement of the shelves and their leveling very easy. The Speed Nuts have a layer of Zorbex vibration absorbing foam on the top of them, which isolates each shelf from the others.
Finish is black with a hard wood trim, and while the structure looks a little rickety when first constructed, when mass is added, it becomes very firm and stable. Stamping and jumping up and down on the floor next to the stand with my not insubstantial weight with the needle in the record groove gave absolutely no feedback to the loudspeakers with the preamp volume turned to maximum. Except for the VIBRAPLANE, no other rack I have had has passed this test. The unit is placed between my two subwoofers, and even with these mimicking dinosaur feet, no feedback was noted. For those without vinyl, CDís sounded cleaner, with more air and hall space apparent around the instruments. It almost brought 16/44 sound up to 24/96 level, and 24/96 discs and DVDís were also improved upon. Enough said for isolation.
One caveat. Do not touch the shelves or equipment while a record is playing, as the system floats so well, that the slightest touch will cause a large DC transient, with the needle and tonearm going bouncy-bounce, inducing one massive thump in your speakers, before they disintegrate to dust or catch on fire. Always lift the tonearm before touching the equipment. If you thought electronic feedback is bad, try mechanical.
A few setup helps and tweaks:
1. Make sure the base of the stand is leveled perfectly with the screw
feet before you adjust the shelves and place equipment, otherwise youíll be
repeating the setup again and again.
2. Make sure that the nuts holding the steel plate to the four suspension
rods are screwed down exactly the same amount, otherwise the unit wonít
3. Blow up the three tubes until the top of the unit is level, and just
suspended from the rack, and then check the clearance of the top from the rack,
and each individual shelf from the side supports to be sure everything is even,
and then check the rods where they exit the tube support to see if they are
centered in the holes. Do this before you place a 275 lb. turntable on top, and
you wonít have to lift it off again. This will save on aggravation and back
4. Decide on which shelves to place your equipment before placing the
shelves before you begin placing them, as they can be adjusted for height, but
with a little difficulty.
5.After all of the equipment is set up to satisfaction, pump up the tubes
with the included air pump until the top is level with a 1/4 inch clearance from
the support, make sure the rods and shelves are not touching the support rods or
the hole in the underside of the top.
6. Finally level out the turntable or transport, sit back and enjoy.
VIBRAPLANE VS. AIRHEAD
Which is better, the Vibraplane or Airhead. Both have advantages.