SpeakerTalk

Richie · Posted: Fri Jan 21, 2011 2:55 pm Post subject: Stands

Its generally agreed that spikes are best on stands, whats the opinion on the speaker to stand interface, cones, spikes or isolation pads ?
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audiolabtower · VIP Contributor 500+ Joined: 06 Jan 2009 Posts: 686

It probably depends on the speaker, but for BBC type relatively thin wall damped cabinets I've always found a pea of blutack at each corner serves as good as anything.

Richie · Posted: Fri Jan 28, 2011 8:45 pm Post subject:

Thanks ALT, I thought the aim was solidity and rigidity, (isolation aswell but all methods address this) blutak, isolation pads and rubber pads would still allow the cabinets to move a little, or is there a secondary aim, not to damage our speaker cabinets.
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audiolabtower · VIP Contributor 500+ Joined: 06 Jan 2009 Posts: 686

The BBC type thin wall, ie a specific type of Finnish Birch ply is actually designed to vibrate, thus they generally have stands that just support the edges rather than sit on a plate which might change the behaviour of the cabinet. The idea is that cabinet colouration is pushed down into the bass where it is not so objectionable, rather than the midrange where it does most damage to the sound. Thus the bitumen pad lining which greatly reduces the Q of the resonances and makes the cabinet "quick" to absorb the energy without it hanging around to colour the sound. Also the screwed on back and front panel, designed to be "lossy" in transmitting energy. All this without adding a lot of mass, which would just tend to increase the Q and make the colouration more difficult to deal with economically.

The BBC did many tests in the 60s against live orchestral sound on thick walls and bracing etc and came to this conclusion with the specific wood and ply construction which gave the least cabinet "sound".

Kef did not use ply on cost grounds, also screwed on panels, but from speakers like the original 104 used bitumen pads internally, albeit with floor grade chipboard (denser than cheaper stuff) and often internal bracing to compensate.

Spikes under the speaker would do just as well I guess if you don't mind spoiling the veneer.

Richie · Posted: Sat Jan 29, 2011 3:06 pm Post subject:

My thanks again, very interesting. Think I might try the cones.
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