Level the floor

That’s a big slope but just because the basement floor sunk or rose in as area, doesn’t necessarily, & hopefully not, mean the foundation walls moved. They’re most likely not contiguous. 

jonwolfpell

 

That’s a big slope but just because the basement floor sunk or rose in as area, doesn’t necessarily, & hopefully not, mean the foundation walls moved. They’re most likely not contiguous.

This is a common shape on houses here.  19th/20th century Illinois; when they were first built the basement was not a useful floor, so much as a "bottom".  The concrete was poured in sometime after, with existing pipes and whatever already in place, so a perfectly level floor would have led to a ceiling hitting heads.

It's not sinking, it was made that way.

So my basement, home of my Man Cave, slopes down towards the sump pump well.  That saved my amp, subs and speakers when we had a flood in 2007!  Don't level your floor unless you are certain that this isn't an issue.

I don't really level much except the speakers, which have adjustable spikes on Sound Anchor stands, and my Thorens TD166MkII.  I had custom feet installed to replace the stock feet.  These have a leveling adjustment range of about 2", and have racket balls on the bottom in inverted cups.  I must replace the balls whenever the old ones lose their elasticity.  But according to several bubble levels, the 'table is completely level.

My wood floor is nearly identical to your slope, it is down 3/4" within the first 24" from the wall, then very little slope after that.

My existing rack, bentwood and glass has supports in the back and sides.

I cut new end ’feet’, hard maple, and tapered, 3/4" higher in the front. Note, they extend a few inches past the back and in front of the rack. Big screws with lock washers hold the new supports to the existing end pieces. Not only level, but increased stablility due to extension of the supports..