Thank you all for the considered and well-crafted replies. All of them. I got something useful out of each one, and greatly enjoyed the morning read. I expected a much lower signal-to-noise ratio than I received from you guys--my mistake.
I am not willing to pay for Townshend Podia at the moment. I am, however, willing to spring for (pun intended) Nobsounds and may piddle with some damping ideas in combination. I still need to build fairly rigid bases for the AV 5140s because their footprint is too small to be sufficiently stable against topling (and this will get worse--to what extent remains to be seen--with the addition of springs). The Linn factory bases went missing long ago, and I don’t think they were "all that" to begin with.
I am not willing to pay for Townshend Podia at the moment. I am, however, willing to spring for (pun intended) Nobsounds and may piddle with some damping ideas in combination. I still need to build fairly rigid bases for the AV 5140s because their footprint is too small to be sufficiently stable against topling (and this will get worse--to what extent remains to be seen--with the addition of springs). The Linn factory bases went missing long ago, and I don’t think they were "all that" to begin with.