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Spikes on tower speakers

This is my first post here, just getting involved in the earlier stages of serious stuff. I recently bought a pair of Piega p4L MKll speakers. They sound great, at least according to my perhaps unsophisticated ears.

My question/problem: The speakers have spikes on them that cannot be removed because the previous owner glued them to the base. Becaue of the spikes, the speakers are very unstable on the carpet in my listening room. I need something that the spikes will go into so that the speaker towers will be more stable. So far, neither plywood nor small metal speaker spike pads have worked. Am now considering carbon speaker spike pads and hockey pucks to get the spikes into and then a bigger base, such as wood or even granite/marble.

I would greatly appreciate any suggestions that would solve this problem.

phil59

Showing 1 response by joshua43214

joshua43214
41 posts
 

Spikes are for coupling, if you have a suspended wooden floor, it will cause the entire floor to resonate.
I tested both coupling and decoupling my speakers, and decoupled was better by far on my suspended wooden floor.

 

As for the speaker moving? Some folks have invoked the Great Isaac Newton, but didn't bother to do any Newtonian Science.

Your speakers weighs 14kg, a typical 15cm paper driver has about 8.5g (0.0085kg) of moving mass and an extension of about 4mm.

F = mass*acceleration

Work = Force*distance or

Work = mass*acceleration*distance

The force acting on the cone and the speaker body are equal and opposite, and the work done by the cone on the speaker is expressed as:

0.0088*acceleration*.004m = -14*acceleration*distance

cancel acceleration and simplify the left

0.0000352 = -14*distance

-0.000002514m = distance = -0.0025mm

your speaker will move 2.5 microns at full excursion.

This is in a frictionless un-damped setting.

If you are curious, a 12" woofer typically has a moving mass of about 100g, or about 11.7 times the mass of a 6" cone. In this case, the same enclosure would move about 30microns, which is in the vicinity of a 12MHz sound wave.

 

We get enough hand-waving junk science from Amir over at ASR, let's not infect this fine forum with more of the same nonsense. 

 

Spiking to a concrete floor often improves the damping of a speaker, isolating a speaker from a suspended floor improves the damping of the floor.

What works best in your system depends on your system and room.

 

I like the idea of setting the speakers on a board of some kind be it a cutting board or a hunk of MDF. Use your feet of choice on the board, spikes will require you to drill some holes and add inserts, isolators can be inexpensive "pucks" you put under the board. I suggest these things

It is possible they are already thicker than your spikes are long and you wont need a platform at all, or maybe you can add something under them like machine felt or heavy cardboard to give them a bit of extra lift.

I probably would not go with anything fancy, these are (according to the Piega manual) entry level speakers.

 

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