Tapping on my table


Searched some threads and did not find an answer specific to my question, so I will try here.  My system is in my basement, which is a concrete slab with wall to wall carpet ( and carpet pad).  My TT is a Music Hall MMF 9.1 which has 3 plinths separated by sorbothane spacers.  The TT sits via its conical feet directly on a Salamander cabinet holding my amp and cd player plus some albums.  Total weight of the cabinet, equipment and albums is at least 150 lbs.  The TT weighs 40 lbs.

I have never experienced any issues with vibration, i.e when walking around while playing an lp.  I had assumed the concrete floor and thick carpet, along with the heft of the cabinet and contents, provided excellent isolation.  However,  this morning I inadvertently tapped the top of the cabinet while listening to an album and there was a very subtle but distinct thump emanating from the speaker.  Clearly the TT is not isolated from the cabinet even if the cabinet is isolating the TT from the floor.

Is there a good inexpensive solution to solve this isolation issue?  I do not want to lose the leveling benefit of the TT's feet - I have some Herbies cones under my cd player, but these would eliminate the leveling capability.
sjtm
There are two issues here, IMO. First is the stability of the cabinet, which is a function of construction, TT mass, and the ratio of the height to the smaller of depth and width. The second is sinking transients to ground.

The solution which I found, because my 150 lb TT dictated it, was to lengthen the width of my cabinet to 40 feet, by the simple expedient of bolting it to the frame of the house. This also served to sink transients to the frame and thence to the concrete foundation. Problem solved. Of course, the wife doesn't yet know there are holes in the Louis XIV desk ...
A good trick to try is to use a turnbuckle attached to the wall and cabinet...tightening the buckles.......amazingly effective.
ct0517,

When using the stethescope method, does one need to worry about damage to the cartridge or any other components?

I will be doing this in the near future and sound dampening everything.

Thanks,
Dustin
Hi Dustin
let’s think about this.
Does it make sense to try this technique on an unsuspended turntable setup, that is directly coupled to suspended springy wood beam floors ? imo, no. why bother? Btw - how many Audio Boutiques have you been to where they are using a beautiful historic Brick and Mortar house, and have a turntable set up on the 2nd floor - wood floors ?
So a stable setup to begin with is needed.

There is always a higher risk with vinyl just by the physics nature of it. The horizontal platter/lp acting like a possible angle grinder on the vertical cantilever, especially on well endowed cartridges, comes to mind.

To help with any worries keep the turntable unplugged, and ensure your phono stage and amp are good quality and electronically stable.

btw

I have learned some good can also come from this exercise, if your wife catches you doing "this dance" in silence. She might think you have maybe just "lost it", ....gone over the top. So you may gain back some leverage.

If you choose to do the dance without the option of waving your hands around; she may also think you are auditioning for Riverdance.

https://www.youtube.com/watch?v=HgGAzBDE454

:^)

Cheers Chris
Yes just don’t tap on the cabinet.

If you are determined to have a more robust stand/platform for your table it need not be expensive.

My room is similar to yours including floor and my table sets on a very heavy and massive 15" tall antique solid oak coffee table (constructed from 1 inch + thick oak wood slabs)  I found in a used furniture shop down south many years ago for $30. It provides a rock solid foundation for the table and the other gear (pre-amp and DAC) that sets on it so no worries ever.  You can tap away and never hear a thing.