Mike, if I can humbly make a suggestion.
I've been running my Stacores passive CLD/air isolators/Rollerblock lateral isolating platforms under various bits of gear.
It comfortably exceeds the active Kuraka piezo electric sensor platform I directly a/b.d.
I've then gone on to try the Stacore under cdp, under pre, and then cdp and pre stacked vertically on the Stacore with a Svelte Shelf to semi isolate the topmost stacked component.
Isolating each component individually has been absolutely wonderful to the extent that I'm compelled to go Stacores on all my gear, 6-7 platforms.
However stacking gear was fine for the component directly on the Stacore but nowhere near as effective for the topmost component.
I put this down to the fact that the Stacore isolates from the environment as well as from the component itself, and so to maximise the latter, the component must sit directly on the Stacore.
And so I suspect Mike all your gear must be as well, except in yr case Herzans not Stacores.
not all gear is equally effected by decoupling. the dense and solid dart pre is the least effected piece of gear I've ever had in terms of either passive or active vibration treatment. and I've found that the top level gear in a stack gets the most advantage. this happened with my Playback Designs MPS-5, with the Aqua Formula DAC, and with the Aqua La Diva transport.
And while you're there Mike,^ get that SGM off the floor. Surely another Herzan or a Stacore would further elevate sound quality and costs pennies compared to what you've invested in the MSB.
Don't know what Mike would think if I bother him with more suggestions like
- putting Select II directly on the Herzan
- putting the 2 mono bases on separate rack levels
- bypassing the Dartzeel pre altogether, driving 458 direct...(with -6db native dsd option)
as my previous comments note; my intention was to have a separate shelf for each unit but the height did not allow for that choice. so I've optimized things for the moment.
regarding stacking the dart pre and the dac box on the Herzan; yes it's a compromise; but it's the best choice I have at the moment. and the dart pre chassis is so dense and solid that it compromises this approach less that almost any piece of gear I can think of. and I'm using BDR cones under the dart pre and under the Dac box too, so any compliance is minimal.
I'm at an in between point with my whole rack set-up right now. there are any number of directions I'm contemplating. I might purchase a whole new different rack system, or expand my Adona rack sideways to allow for more shelves and a separate shelf for each box and the possibility of a separate active unit for each as my budget allows (and I'm thinking about where my dollars will take me farthest).
I need to plan strategically for an end game of how many boxes I will have (going forward) including my server and grounding boxes (Tripoint and Entreq) now sitting on the concrete floor (each of which are certainly tweaked now as they sit in terms of platforms.....a concrete floor has it's attributes as a support).
as far as bypassing the dart pre and going direct; now that I have the mono powerbases I will be trying that, both with a long set of RCA interconnects to the amps, and using 'rca <-> bnc' adapters to using my Zeel intercomnnects to my amps (which is what use from my dart pre to my dart amps now). I will also try the adapters with a short zeel interconnect to the dart pre instead of the Tara GME IC's.
that is my 'next thing' to do.
bottom line; everything sounds heavenly on all formats (digtal, vinyl and tape) as it is, so I do have time to make sure my next move is the right one.