I was clearing out my things when I found my guide book for the Kryna D-Prop and C-Prop footers. Will post some pictures later. It shows recommended positions for their footers under various components.
Kryna has a slightly different approach. I can't read Japanese but from my conversation with the dealer, and guessing from the diagrams, different model footers are used depending on whether the supported point is (i) being isolated from external vibration or (ii) a source of vibration. Example (i) would be the circuit board of component while (ii) would be the CD player spindle motor, transformer, turntable platter and tonearm bearings.
I copy and paste a google translate from their website,
In the case of the active equipment by itself be a source of vibration, you must insulator is a mechanic diode.
(A) vibration is hard got,
drop in (B) vibration (A).
Let's use the spike type of insulator of easy to tell the vibration material.
(When choosing the insulator, note the impact of the material-specific sound.)
KRYNA of D-PROPextend as of, the effect as a further mechanic diode will be higher and to the spike double (double spike structure).
Here are some pictures,
I am assuming that the footers should be placed with the centre of gravity in the middle of the triangle created by the three footers.
Some suggestions on placement.