Anybody use HRS EXR racks -any feedback (or maybe lack thereof lol)?

@inthesticks 

I don’t think I really needed the HRS isolation base for the Boulder phono, but I already had it before. I still wanted the upgraded M3X2 base for the TT.

Also, unlike the higher end HRS racks, the shelves are included/integrated with the EXR. It's just the added isolation bases that are cost options.

The Link will introduce the OP to other forum discussion on Active Isolation.

Wise Purchasing will discover B25 Panzerholz @ 25mm thick for approx' £100 per 500mm x 400mm Board.

 https://www.whatsbestforum.com/threads/adding-a-5th-taiko-tana-herzan-ts-140-active-isolation-unit.27685/

@mulveling I should add, in addition to the ERX rack, an S3 isolation shelf add-on is proposed specifically for the techdas turntable.

@mulveling I should add, in addition to the ERX rack, an S3 isolation shelf add-on is proposed specifically for the techdas turntable.

If it’s like my experience with Critical Mass Black Platinum / Diamond / Maxxum shelves (i.e. rigid, or semi-rigid constrained layer damping in multiple layers) - an S3 would help mainly in the midrange frequencies and up (yes the CMS shelves were effective here). I suspect it will not be very effective at isolating LF / bass energy (rocking modes), if that’s in fact your problem here. But the HRS’s rack structure itself should help you a lot - just make sure it’s located on very sturdy ground. Ideal if you’re on concrete slab - and I think that’s where a topper shelf like the S3 could really shine. 

IMO whomever is advising and suggesting HRS should also be taking your floor structure and rack positioning into account. This is already way WAY too much investment for feedback problems to be acceptable! I got burned bad on the CMS Sotto Voce, what a horrible product - rocks like a bastard, makes the expensive platforms resonate like a drum skin; I could go on. I also have their CMS Maxxum (different system), which is completely different to SV and works very very well, but costs a LOT (was it really worth it)?

If your floor is bouncy and your problem is woofer flapping (subsonic), a cheap hack you can do is to brace the rack against (or anchor it to) a wall. You can even just push it up against the wall with some foam between. At some point if your floor is really bad, you'll need to do this - no matter how rigid and massive your rack is. This made my SV usable, though in the end it's still better to do this with a properly rigid rack. 

HRS isolation bases do broadband or low frequency isolation, depending on the feet that are configured when ordering. My M3X2 was factory configured with the correct feet specifically for my turntable. HRS states the LF feet isolate components from below 10 Hz to above 40 kHz.