Thank you for the compliment Detlof.
Vince. I would be surprised if the electrical isolation you mention is not degrading the Io. Every device I tested provided negative results in my system. The large Accuphase was one of the best, but limited the total dynamic range in addition to being extremely expensive. Depending on your location and the quality of your electrical service, your results may vary.
All of my Aesthetix gear is powered through Purist Audio Dominus power cords. They have consistently out performed every other cable. My testing included, but was not limited to: MIT, Audioquest, Power Snakes, Synergistic, Music Meter, Tiffany, Tara Labs, TG Audio and three hospital/shielded grade cables. I am about to test a new heavy gauge power cord from Vantage Audio and will report when I have conclusive results.
As far as the Black Diamond cones, I have had less than stellar results with these. The Io is an extremely high gain all tube phono and is highly sensitive to both mechanical and airborne vibration. Most of the cone type isolation devices provided marginal resistance to microphonics and added an unnatural brilliance to the upper mid and/or upper high frequencies.
My isolation evolved from more than two years testing and finalized with an extremely ridged 6061 aircraft aluminum stand that was TIG welded, Nextel coated and partially filled with Silica. The stand is four cylinders, quarter inch thick walls with twelve cross braces ( three per side) and has three quarter inch aluminum discs welded into each cylinder ( top and bottom ). All eight discs are bored and threaded to use a one half inch diameter tempered stainless steel spike ( NF thread, 45 degree point ). I use only the bottom spikes, as the top ones were a sonic failure.
On top of each of the four cylinders are McCormack Audio Soft Shoes placed upside down from their usual orientation. Atop that is a piece of polished natural Granite ( 17" X 22" X 2" ), and between the granite and the Io are fourteen of the small IsoBearings ( 2 Kg rating each ) by AudioPrism. On top of the Io are three of the Walker lead and copper disks, ( one thick and two thin ) with the optional leather damper between the disk and the Io's top plate. The two power supplies ( probably one in your case) are not as critical as they do not contain the primary audio amplification tubes and RIAA equalization circuitry.
Using the smaller IsoBearings in such quantity provide extraordinary isolation from both airborne and floor vibrations. Other devices tried here were the Walker Valid Points ( with and without the lead discs/both thicknesses and with and without leather damper ), Mod Squad Tip Toes, Purist Pyramids, the large IsoBearings, Black Diamond Racing (#4, #5, #6), Sound Anchor Cones, Goldman Cones, Simply Physics cones (all three types), Carbon Blocks, Mod Squad Soft Shoes, AQ Sorbothane (Navcom), E.A.R. TAD, Audio Points, Symposium Roller Blocks (with upgrade tungsten bearings), and the Neuance shelf ( with and without most of the above cones).
As with all isolation, the results are judged by a combination of the room and the system. Interactions with your acoustic environment, your foundation ( slab or suspended floor ), the sound pressure level, the microphonic tendencies of the tubes you select and the tonal balance and tuning present from your other equipment.
In short, you will need to test multiple isolation devices in your own system to determine what works in your situation. I will reply to direct questions at this post or by private email. I am also willing to spend time with you on the phone if that is more comfortable than typing.
