@viridian Yes, I didn’t really want to pull the plug with a record playing, but I did. Turned up up volume, and no ’howling’ at all.
@millercarbon I didn’t want to, but finally moved some furniture out of the way, and set the turntable on the floor, right next to the stand. You are right, this eliminated virtually all of the 10" acoustic coupler rapid movement/rumble (not a noise, just the rapid movement).
So, damn I thought, I really don’t want to put this thing on the floor. So I tried a couple of things; what if I put a thick piece of styrofoam below the whole table on the shelf? Have some in the basement from various exquipment packaging, brought it up, set the table on it and it was much much worse. Next, got some large tiles I have in a box, figured perhaps what is necessary was additional firm support. Nope, didn’t help. In fact, it seems anything I add under the feet, made the situation worse.
Took off the platter and belt, locked the arm, and removed the head shell. Turned it over and inspected the feet. Over the years, 2 of the three feet had somewhat collapsed at the isolation sections, and two still had the iso section intact on the feet where they screw into the base.
Which got me thinking...seems to me, more isolation, or anything, under the feet is created more issues, not less, so, what if I take off the feet entirely so the table base sat right on the wood shelf? Looked into the service manual, made sure the base would come off easily, it would, so removed it, and then removed the feet entirely (the screw attachment to the feet were on the inside base side). Reconnected everything, put on a record, and lo and behold, probably 88% of the sub/coupler movement was reduced/eliminated. Only when I cracked it way up did it start acting up, but again, way beyond the volume level with the feet on.
But, the vent ’grate’ to the motor probably needs room to breath (ya think? ;-) ), so this is not a good solution, but what it told me was the more I could ’connect’ the table and the stand/shelf together, the better off I would be, short of putting the table on the floor. This seems reverse thinking of what we tend to believe with most audio equipment, but I may have to look for ’solid’ replacement feet, and not feet with any type of absorption or isolation qualities.
I think my problem is that I have an old house, with fairly bouncy old wood floors and structure, and the large Vandy’s sitting on the floor transmit a lot of energy and movement into the floor via the anchor stands, and thus, transmit the same into the large loaded stand adjacent to them. So any ’typsy’ feet on the stand is going to react negatively, especially ’tipsy feet’ of a turntable.
So, the filters that are coming are useless to me, and I’ll probably return them immediately. Good news is that the Schiit Mani is a good choice for a phono stage, as a filter is not really necessary.
So now I have to figure out what type of solid raised platform or feet I can get which will be ’as connected’ to the shelf/stand as possible, not isolated from it. The only other options are to set thee table on the floor, get a separate turntable stand, or get one of my carpenters to build a wall mounted shelf. None of which I would prefer to do.....yet.
I can’t thank you guys enough for all your thoughts and ideas thus far.