Replacing the stock umbilical definitely improves sound,quite a bit.Seemingly rediculous,but my pal,and myself(who both have a COSMOS III)concur.You don't have to get NUTZ with mega buck umbillicals,but get something good.Just make sure the connections match.We,also use a good after mkt cord,but this should be no surprise.Though the suspension is superb,it doesn't hurt to have a good shelf/stand.The better,"the better" performance will be had.
Also,the vacuum sounds MUCH better WITHOUT the intermat.This is inargueable,and we have compared on loads of occassions.LOSE IT!!Peel the intermat off,and swab the glue with alcohol,to smooth out.Be careful,and you will be shocked as to how much more dynamic,and detailed it can sound.Keep the platter clean with a nice soft brush(like a make up blush/brush),and you will NOT develop noisy discs!!I get the distinct impression that the bullshit about vacuum systems sounding worse than non vacuum versions,or that noise develops easily,on LP's,was started by competition.Of this I'm convinced.BTW--I've had vacuum SOTA's for over twenty yrs,and have no new pops or clicks.Yet I exercise common sense,in maintenance.
Finally,the SOTA reflex clamp is OK,but can be improved.Here's what we do--Loosen the clamping action,so it actually rests on the lp,instead of clamping,which you don't need anyway.You want it to act as more of a weight.Stick a thin sheet of cork,YES CORK,under the clamp.You can buy this for about three bucks,at any Home Depot.Try to find it in sheet form(for use as a draw liner generally,but you need about three inches).Cut it out to fit on bottom of the clamp.This dampens out a resonant frequency that is given off,to the lp,by the clamp.DON'T BELIEVE ME?Try clicking the outer edge of the reflex clamp with your finger nail,as you would do with a wine glass!Hear that PING.You want to stop that sound from transferring into your vinyl.It makes a real improvement,and costs pennies.Try to get cork sheeting with one side of stick.This can be peeled to allow for good contact with clamp.The sticky side,ONLY,to contact clamp.The other side is your cork,which doesn't allow transfer of that nasty ping,to your discs.If you want to go crazy,for an extra ten cents,you can double up with two layers of cork,but it really isn't necessary.Remember,unless you are a klutz,you should not see any corking,and it should be cut to match the roundness of the clamp.Really cool,btw.
All these little tweaks,my pal and I have learned from careful attention to detail.Maybe someone else can add a good tweak.Anyway,the SOTAS are rediculously good tables,and are well priced!!