Level the floor

You could try something as simple/cheap as hockey pucks. 

I would concentrate on the audio rack holding the CD/TT.

Do you have enough adjustment in the front back spikes?

What type of floor surface?

DeKay

What is it exactly you need fixing??  The equipment rack? Speakers?  Turntable

With speakers, so long as the slope is consistent there's no issue.  The speakers will tilt down but so will your seat.

Having said this, it's worth noting many speakers sound better listening below the tweeter axis, and with less toe-in than pointing straight at your head so worth while listening before attempting permanent fixes.

My living room slopes a little.  My 4' towers were out about 1/2" out at the top.  The speakers and iso-insulators sit on 16" x 16" x 2" concrete blocks.  I shimmed out the edge of the concrete block where it meets my carpet.  No difference in sound that I can detect but it looks better.

Yeah, I had no idea to even start with this.  For example:

You could try something as simple/cheap as hockey pucks.

I had no idea!  (I don't suppose there's a preferred brand of... no no no ignore that.)

So, first: thanks for the questions.  Somewhere to think from.

Type of floor: carpet on top of concrete.  Changes to the carpet, like cuts of sections, for example, are out of the question.

Adjustment on the front of the system stacks: I'm guessing the question there is, can I change the shape of the equipment stack itself?  If so then the answer is, "no", it's a series of steel needles on a metal frame.  For this part, I think "pucks".  Done.

The speakers are my main concern.  Each channel involves two sections:

A small, light channel expects to run near eye-level, standing some inches away from the main stack.  Here too I think "pucks", done.

The primary speaker stack is my chief concern.  It weighs about 120 lbs, measures about 20" deep, 16" wide, expects to sit near floor level.

These speakers are known for being room-sensitive; tweak, shove, tweak AHA!  Glory!  ...so adjustability is important; standing it on sets of spikes of adjustable lengths wouldn't be good.

Currently I'm thinking: first layer, pucks; on top of that, a flat sheet of something that we set between the speakers and the pucks.  "Something simple and cheap" would be grand, but nothing is springing to mind.  Stability is obviously important, non-resonance...  Light weight would be nice, but flimsy would be bad.  Ugly, I don't care, sheets of fabric solve all things.

I do have some access to tools.  While "two circles of steel" would be a dumb idea (uh, right?), something similar to that might not be out of the question, depending, maybe.

Thanks, all.

Leveling your listening space/chair is a big deal...one more thing to check off tweaking.I used lazer to get as close as i could ear level listening chair.

Yeah.  At this point, cushions atop chair, mix and match, but, yeah.  One issue at a time.

I think you are on the right track. If you have some Mooney, you might go for Black Diamond Racing Carbon Fiber platforms… then use Vibrapods, or audio pucks (there are many variations) under the platforms. Short ones under the high side and thick ones under the low side. 
 

It is not expensive to get scrap granite… and have it cut. I use this for my amp… with vibrapods under and Nobsound springs above. 

You could try something as simple/cheap as hockey pucks.

I had no idea!  (I don't suppose there's a preferred brand of... no no no ignore that.)

When I was growing up playing ice hockey pretty much all the pucks came from Czechoslovakia, so if you can find some of those vintage pucks — since the country doesn’t technically exist anymore — I’d guess those NOS pucks would probably sound best.  Ehem.  I have a similar sloping concrete basement floor issue and have used generic hockey pucks when needed and noticed no sonic degradation FWIW.  That said, since you’re on a concrete slab I’d skew toward getting some granite slabs cut to size at Home Depot, etc. and just do that.  Either way I’m sure you’ll be fine.  If you’re more OCD about it you can see how much it’d cost to level out the basement floor with some added concrete.  I thought about that but my hockey past and the pucks ultimately won out.  Best of luck. 

Ehem.

[exhale]  Well done, well done.

I had no idea that custom-size hunks of granite were cheap, and/or subject to such fine specs.  See, this (and others) are just the info I came in without.

Thanks, all.

A slope of 1 inch every 18 inches?  Across the whole length of the room?  How is your house still standing? 

Make some pads.. Screw four 2x4's together and make a box the size you want. Coat the insides with Crisco. Mix some self leveling concrete Fill to the thickness you prefer. Easy

When I was a kid our basement floor shifted (bentonite clay). A contractor came in and fixed it, I think a combination of mud-jacking, and a leveling concrete thin layer. Ours was pretty dramatic, I only mention it because there are contractors out there that specialize...

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..

Again, trying to understand the problem. The only item which MUST be level is a turntable, and that is usually easily fixed.

Otherwise, so long as your floor is flat there's no real issue I can detect.

eric,

even if the turntable is leveled, in OP's case by putting 1" high 'lifters' under the front feet

if your rack is pitched forward under the turntable, the combined weight of all other components is also pitched forward, fronts of each piece lower than the rear, add the combined weight of my 3 glass shelves pitched forward: any vibrations will more readily rock the rack forward then back ...., it is far better to level the rack and have all the combined weight be a downward force.

The only item which MUST be level is a turntable, and that is usually easily fixed.

Right.  This floor is not flat.

As discussed (and, okay, discussed...), this is some serious tilt.  I wouldn't want to have a desk that tips this much.  Okay, so, stick some books under the desk -- 'tis the way -- but sound-making machinery is prone to Surprises and I didn't want to learn that I'd solved this the dumb way when I heard a bang.  So, I asked.

Turntable: pucks.  Huzzah.

Speakers: I wouldn't want to run those on a tilt either.  Call me picky, but this set is modular, irreplaceable, with some heavy magnets at the top, and this much tilt makes me nervous.  I also want to be able to adjust them, the floor is carpet, that can cause surprises, and and and.

I've learned, for which I'm grateful.

OP:

Each issue has it’s own fix. Speakers often have adjustable speaker feet/spikes which can be used, as well as speaker stands with adjustable feet.

Stone countertop places have all sorts of scrapes around. Find small pieces they will never sell. 

mrj OP

I was assuming the speakers would be forward from the back wall, to place them on the very gradual portion of the floor. Thus, shims ought to work.

In any case, I believe speakers should be tilted back so that the tweeters are aimed at seated ear level. This will involve tilting, usually accomplished by a block or riser in the front.

In my case, concealed by the lower ’skirt’ I have attached a 1-1/2" block in the front, the 2 front wheels attach to it, thus the rear single wheel, with no block, keeps the rear of the speaker 1-1/2" lower. Blurred, hard to see, bottom of image

Easier to see, 9th photo here, as well as the speakers in-place tilted

https://www.audiogon.com/systems/9511

My heavy speakers can be on wheels, lighter speakers can be on ’skid’ plates, allowing alternate toe-ins

KLH OEM stand tilted their speakers back 8 degrees

JBL Speaker Stands

For Klipsch (they made their OEM ones also)

Custom, get smaller speakers higher and tilted