I got hold of some slate that i am about to cut to size to sit under each speaker. I may also be able to get another piece of slate of the same dimensions. Would it be worth while using 2 pieces for each speaker, so it would be - Speaker sits on spikes onto top piece of slate Top piece of slate sits on sorbothane blocks that then sit on bottom piece of slate Bottom piece of slate has spikes/cones to the floor. A bit like this -- Where Black = slate Green = sorbothane yellow = cones/spikes
Similar yes, but i am hoping that it may be more stable than inner tubes, and not kill the sound like my granite experiment.
Looks very nice! In place of 'yellow cones/spikes' you might get better results with Oak Cones from Russ Andrews.
Floor is suspended wooden with carpet. I found the michell cones work ok, as they have a sharp point that can penetrate carpet. Just finished cutting the slate (20mm thick). washed and waiting for it to dry. For now it will be just one piece of slate as i dont have the other yet.
Might be worth a try with sheet or squares of sorbothane between the slate. Should also be a little more stable
not a bad idea, i think the sheet comes in 6x10 inch. I could get 2, cut them in quarters and place in the corners.
Sorry Paul, my mistake, i dont know of anywhere else. So from 6x6 i could get 4 3x3 squares, i would imagine that would do it with 2 sheets. I cut the piece of slate today so i now have speakers spiked to slate and slate with cones to floor. With that set up the detail is better, highs less brass like and overall a nice balance. bass is better defined but not much wieght to it, although i havent cranked up the volume yet.
That could be the better de-coupling from the floor, your just not hearing the floor board resonance anymore
An alternative is to attach the mass [slate] to the base of the speaker cabinets. Handily the speakers come with suitable threaded attachment points. This has the effect of stiffening the cabinet , lowering the centre of mass and altering the resonate fequencies within the speaker. This energy sink can then be spiked to the floor. Not certain how the energy storage method will work [sorbthane]. Some speakers work well when you allow them or there parts a bit of movement but they are few and far between. Only the roksan with the floating tweeter come to mind.
I wonder if soft materials under speakers will react to cone excursions and vibrate (micro rocking?). My strategy therefore is to use hard materials such as granite under the speakers and plant firmly to floor using spikes. Then isolate components using soft materials such as sorbothane. Any comments?
Largely the use of isolating speaker supports is to decouple the speaker from a suspended wooden floor (I don't think I'd bother if I had a solid concrete floor). Using hard materials won't really do this. Having soft isolation under other components works for me (I use bubble wrap), to damp vibration in the kit.
IMHO you need to get straight in your head (or maybe we all do actually) what one's trying to do. One school follows the mass-spring-damping idea, which fits with the slate/sorbothane, in which unwanted vibrations coming into the speaker from the floor are converted to heat (and maybe the other way too, to stop the floor booming). This school says that the movement of the speaker on a compliant spring (sorbothane) caused by driver-movement is tiny and not significant. Another school says that the speaker should be rigidly locked to the floor to prevent it moving - hence spikes - and to provide a sink for cabinet vibration. Either of this could be correct or spurious, for all I know. Which one do you want? At a minumum, spikes and sorbothane in the same stand seem to be mutually contradictory. I'll leave it to you to research the answer
That's an interesting post Steve, do you, or others, think that by having the sorbothane in the middle you get the best of both worlds, i.e. a rigidly locked stand to the floor, therefore isolating the speaker for foot steps etc and the damping effect in the middle allowing the speaker to move and disperse energy. I'm currently trying all these methods and very interesting they are indeed, well at least to me, my girlfriend is very understanding and just thinks I'm mad and perhaps a little sad.
I have done some experimenting here, I also have a carpeted suspended wooden floor which the base used to thunder through. Firstly forget the spikes (they do rock, just push one) drill the slate and screw through the carpet into the floor, makes no bigger hole than spikes but provides a stable platform even bracing the floorboards. Next forget the second slate (would look odd anyway) and forget the spikes (they can dance on hard surfaces) place the speakers on sorbathane feet directly on the screwed slate. Try and rock your cabinet you'll find its remarkably stable, more than any spiked array. Also the sorbathane sheets are only 3mm thick and are for damping casework, they dont have enough give in them to suspend speakers (the IXOS ones are unbeatable IMO). This transformed my sound beyond belief, I realised I had been listening to floorboard boom for years! The speed is there, bass is less but sooooooo clean and the top end is more detailed and smoother. I also tried bolting slate onto the speakers through the spike holes and then screwing the slate to the floor. My reason is the theory of making a rigid conection for speakers, they were planted but didn't sound anywhere near as good as the above. If you wan't any details drop me a pm
screwing to floor is out unfortunately, as its not my house So if i stuck with cones on the bottom and sorbothane blocks between slate and speaker would that be near to the ball park?
Yes and no, the coupling/decoupling is what many see as the ultimate, by using something coupled (screwed slate) gives a perfect base to decouple your speakers (sorbathane/air plat) from. My own experience with sorbathane is it removes the floor colouration, either stops the cabinet transmiting to the floor or the floor transmitting to the cabinet I think probably both. true the speaker may now move a bit but as the clearer sound shows, less than it does when coupled to a vibrating floor.