question about TL boxes

[busterno1]

I am planning on having a go at making some TL speakers .

But one thing I have noticed is that on some of the boxes other have made they use something like a brush on tar or a tar backed paper to stiffin the center piece of mdf in the box .Yet others dont .

Is it necassery to do this.Should it be taken into account as part of the dampner thanks

[mrfeedback]

TL's rely on the internals of the box being quiet.
Any rattling/resonance of internal panels will be clearly evident.
Most old TL's were quite fully stuffed with sheeps wool to quench internal sounds.

Eric.

[paulspencer]

The filling will affect the bass performance and smooth out the response, as you can see from simulations using Martin King's Mathcad stuff.

Dampening on the panels won't affect bass performance IMHO. They serve to make the box more dead and are inexpensive and worthwhile, although I'm not convinced they are essential. I use open cell foam to line mine, I line half of the unstuffed portion of the line.

regards,
Paul