You are on the right track but I seriously doubt it is acoustic, it is almost certainly mechanical. Speakers on spikes transmit energy right through the floor, up the wall and into your turntable. Same happens with CD just nowhere near as obvious. When it is gone you will hear it though even with CD.
Concrete floor, one of the great misconceptions is you cannot have these problems because, concrete floor. But concrete transmits vibrations just fine, only the frequency and speed of transmission varies. There is nothing inherently vibration damping or absorbing about concrete. Quite the opposite. Rings like a bell.
So your solution is very simple, what you need is to isolate the speakers from the floor, and the turntable from the rack. The SRM you are using is kinda sort okay, better than nothing, but obviously not enough.
There's a couple ways you can go. Least expensive will be something like Nobsound springs under your turntable or under the SRM. Not sure which one you have. The one I found on-line is not very impressive but it could work as a shelf with springs under it. You can use these springs under the speakers as well. Very effective. Surprisingly effective for the money.
If you can afford it however the best solution will be Townshend Pods and Podiums. Which is best will depend on the size and weight of your Rega. Podiums for sure will be best under your speakers. The vast majority of your problem is coming from direct transmission of vibrations from the speakers through the floor and walls into the turntable. I had this even with my massive 750lb turntable rack. Dramatically improved clarity and detail.
Not cheap but will totally solve your problem, while taking your whole system up a step in the process. Or if you want to try Nobsound springs do a search, there was a very informative thread on them last year. I used them before going to Townshend, they really do work, quite well in fact, just nowhere near as good as Pods and Podiums.
Concrete floor, one of the great misconceptions is you cannot have these problems because, concrete floor. But concrete transmits vibrations just fine, only the frequency and speed of transmission varies. There is nothing inherently vibration damping or absorbing about concrete. Quite the opposite. Rings like a bell.
So your solution is very simple, what you need is to isolate the speakers from the floor, and the turntable from the rack. The SRM you are using is kinda sort okay, better than nothing, but obviously not enough.
There's a couple ways you can go. Least expensive will be something like Nobsound springs under your turntable or under the SRM. Not sure which one you have. The one I found on-line is not very impressive but it could work as a shelf with springs under it. You can use these springs under the speakers as well. Very effective. Surprisingly effective for the money.
If you can afford it however the best solution will be Townshend Pods and Podiums. Which is best will depend on the size and weight of your Rega. Podiums for sure will be best under your speakers. The vast majority of your problem is coming from direct transmission of vibrations from the speakers through the floor and walls into the turntable. I had this even with my massive 750lb turntable rack. Dramatically improved clarity and detail.
Not cheap but will totally solve your problem, while taking your whole system up a step in the process. Or if you want to try Nobsound springs do a search, there was a very informative thread on them last year. I used them before going to Townshend, they really do work, quite well in fact, just nowhere near as good as Pods and Podiums.