Sorbothane hemi-spheres under my Tannoy Berkeley’s (4x 50 duro for 35kg) enhanced the bass / mid-bass of my speakers.In my experience with sorbothane, i advise you one day to try instead duro 70.... Select the right hemisphere diameter for the weight of your speakers but take duro 70.... It will be better for sound i am pretty sure, i use them for all my headphones damping and duro 70 was surprizingly the better to damp the sound because of his higher density....😊 Wait a year and replace them... Anyway the sorbothane material suffer fatigue with time.... It is a good idea to replace it one or 2 years apart especially under heavy load....I dont use my 7 headphones at all they are way less good than my speakers now.... Thanks to my embeddings controls....
Springs indeed would be better but it is not always possible because of some unstability ....In a living room i could never use them save at risk from children or even adult accident.... My speakers are even on heavy damping load .... Results are amazing but stability is good only not ultra safe....But anyway it is in my audio room and all is ok here...even my wife knock at the door and my grand children were even fearful of my audio room at first, now everyone is fascinated by my "madness" and my high quality sound also tough....
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