Isolating bookshelf speakers without stands?


My smaller listening room is so small that I have no flexibility in where I place my Quad 12L bookshelf speakers. They have to go on the ends of the same desk I sit at while working at the computer. On passages of low-frequency music especially, I can feel vibrations coming from the cabinet through the desk.

All the Quads have, like most bookshelf speakers, is four tiny rubber pads to separate them from the surface they sit on. My question is what reasonably inexpensive product I could use to achieve further isolation: sawed-in-half squash balls or triangular points? Or are they only for components? An isolation platform of some kind?

Any suggestions welcomed with thanks--
apspr
Points or, better, cones are the only things you can use under speakers without sacrificing some bass response, although Totem and perhaps others use steel balls. ( I've heard Totems so equipped and they didn't seem bass-shy, but who knows what difference spikes would have made. )

You want to create an impedance mismatch with the support surface ( that's the reason for choosing a cone shape ) and also couple the speaker firmly to it ( hence the point, which digs in and won't move ). The impedance mismatch keeps vibration out of your desk; the firm anchor provided by the point stops the driver cone's motion from being wasted on pushing its enclosure in the opposite direction.

However it is just possible you don't want to make holes in your desktop with points. In that case you might look into a cone or spike equipped with a cup or base to receive it. Of course with this you have sacrificed some anchoring to the desk and you will need to make sure the cup sticks fast.

Here's a Web page from UHF magazine which describes Superspikes and Tenderfeet, both possibilities for your application.

Spikes etc. at UHF
someone has been selling cork and rubber squares on both audiogon and ebay for 4 for $10. They work nicely and seem to be the same as Mapleshade's.
A friend of mine owns a pair Totem 1s, similar to yours physically, and he went the big, heavy slab route: he had two slabs of 3" granite cut, roughly to the dimensions of his speaker. given the dimensions, this is not too heavy. Blue-tack between speakers and slab, rubber feet between slabs and desk, and voila. Nothing says it like brute force. Tiptoes under small speakers, or large speakers for that matter, tends to make the bass disappear bye-bye.
cones are going to couple the speakers to your desk, and they really won't do anything to fix your problem. likewise, herbie's footers have a pretty high resonant frequency (by design... they're intended to damp microharmonic vibrations) and they would again act to couple the speakers to the desk for vibrations below that resonant frequency. (i'm not trying to attack his product, i think it's a great one in fact and i'm sure steve would agree with my assessment in this application.)

what you need is something soft and squishy, with a very low resonant frequency. i make footers that would work well for this application (pandathumbaudio.com), but vibrapods would work just fine and so would something like a small deflated innertube. you might even try a roller bearing device, as it will decouple the speaker from the desk for vibrations in the horizontal plane.

of course, everything i suggested will cause bass attenuation... but there's really no easy way around that if you want to isolate your desk from the low-frequency vibrations. there's no way around newton's second, after all.

-Gary