Isolating bookshelf speakers without stands?

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

Vibrapods....

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.

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.

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

--Sorry, Gary. I disagree. Because of the open-cell structure of the material, Herbie's footers have no resonant frequency -- if there is, it would be a very, very low frequency. Herbie's footers do not "couple," rather they isolate by absorbing vibrations between and within two surfaces. As for the post your message replied to, Herbie's Tenderfoot isolation feet are ideal to isolate bookshelf speakers from a desk and are used by many customers for this purpose (usually speaker/shelf or speaker/table combination). The isolation material is a silicone-based formula that has some "squish" to it, yet is firm, sort of like a wax. It does not resonate at certain frequencies like vibrapods or rubber-like devices and therefore does not introduce anamolies such as bloopy bass or rolled off highs. It's extreme neutrality is due to the fact that it has no discernable resonant frequency of its own.

Thanks,

Steve Herbelin
Herbie's Audio Lab

I went through a similar conundrum for my ProAc Tablette Reference 8 Signatures, and ended up trying sorbothane pads. These have worked out quite well, though I did not try any of the other methods addressed above to compare.

Do I REALLY have to pay $70 for a set of blue Sorbothane pads or can I buy a sheet of black Sorbothane for $18 and cut them myself?

There are also the Primacoustic Recoil Stabilizers, but honestly, stands are best.