Does any Audiogon member have a Holbo air-bearing turntable?

@tablejockey 

will you be using an inline dryer for the airline

Was not going to.  Moisture condensation may be an issue with bigger pumps that are in a different room and at a different temperature than the table.  The Holbo pump / power supply is reputed to be near silent and is normally within 6 feet of the table and in the same room.  Very little air is actually moved by the Holbo pump!

Do you close enough to the ocean to need, for example, stainless steel guttering?

Where I live, I am more concerned about dust so I may end up with a ventilated box around the pump to minimise airborne dust.

Whart, you mentioned null points and antiskate in connection with linear trackers. In LT tonearms, the stylus is constantly at a null points, there is no skating force and no need for antiskate. However nothing is ideal and for some LTs the stylus travels in tiny arcs across the LP, in which case there would be a tiny skate force constantly changing in direction (toward the spindle then toward the outer grooves, back and forth). It would be impossible to correct for that and not worth the trouble.

@lewm 

The problem you are writing about does not apply to the Holbo air bearing LT tonearm. The Holbo tonearm is an air bearing that floats on the air, has no friction and the needle is always exactly in the middle of the groove.

@lewm you stated: for some LTs the stylus travels in tiny arcs across the LP, in which case there would be a tiny skate force constantly changing in direction (toward the spindle then toward the outer grooves, back and forth).

Curious which LT arms do the above? 

@frazeur1 

getting the foundation right with the table upfront is best anyway

I asked Bostjan what his turntable is sittng on.  He told me he has a big block of Medium Density Fibreboard weighing 20-kgs which sits on four Sorbothane 50-mm hemispheres.

I got a chance to weigh one of my sandstone slabs, and my estimate of 20-kgs was wrong - try 27.5-kgs.  Two of these plus the turntable will exceed the rating of 60-kg per shelf for my SolidSteel S3-3 rack by about 7-kgs.

It was an interesting exercise with Sorbothane working out what size, shape and "durometer" to choose.  Their Engineer in Ohio suggested four 1" disks, each 1/2" thick with Durometer of 70, giving a resonance around 12-Hz.  This would be roughly where I would expect arm resonance to occur.

The local distributor had stocks of 50mm hemispheres in Durometer 50, so I have ordered eight - another A$100 down the gurgler!  My guess is the natural resonance will drop to around 3-Hz if I use them all.

My partner has had a cancer scare with one of her hemispheres, durometer unknown, which has delayed me going home and setting up the Holbo and hence delayed my report back to you.  I can say that the ordering and delivery process was seamless.  The box just arrived, no customs interaction, much quicker than I expected and exactly as Bostjan had promised.

On another thread about cartridge tracking weights, there was a reference to an Audio Technica webpage with a link to a cartridge review.  I was thrilled when I learned that it was reviewed in a Holbo Mk2