Adding 6 Nob loose springs under the six tube phono amp brought improved clarity, musicality, vocal diction, speed and dimensional perception of instruments in the soundstage. BUT it reduced bass weight and enhanced upper mids to the point of coloration.They are not enough compressed.....
The rate of compression must be adjusted around 1%..... On any springs application if i go with my experience with mine....My speakers rightly adjusted gives me the better natural timbre i ever had but it takes me few days of listening....The first sign that all is rightly adjusted is NOT first the clarity, it is the naturalness of timbre, at first this new clarity induce me in error..... To decide we must listen to instrument like violin higher notes to hear their timbre, etchy or natural, lacking body or not.... :)
For turntable(i dont have one) mass loading the springs under the turntable, like recommended by rixthetrick, is the solution indeed....Then it is possible to adjust by varying the loading mass by ears around 1% ( + or -).
Using prings is NOT a tweak....
It is one of the essential way to embed the gear in the mechanical dimension of his working use....
"Tweak" are minor refinement or not, not always necessary..... Springs are indispensable tool to embed any gear in their vibration/resonance dimension (mechanical)....Tweak can modify or adding something that is not always wished for ( like my "sandwiches" that were a tweak wanting to be a control method but lacking the power of springs to be one)....Controls methods for the embedding DONT ADD something, rather they put the gear in the best of his conditions to reach his optimal level....Springs are essential and dont change the tone of my speakers at all if they are rightfully adjusted, rather they reveal the TRUE color of my speakers under the condition where vibrations/ resonance are controlled... Tweak are a fad + or - useful, or an attempt , a bid + or - successful, springs are necessary tool to any speakers.....
Just sayin for those who thinks lightly, or superficially ... :)
A bought bunch of tweaks will never be a method of listening experiments....