Help with Unibox

[todd95008]

I'm using Unibox to tune a ported/vented design and want to get more info/detailed descriptions on exactly what to enter for the following:
Physical Vb
Aborption Qa

The design is with a 38 a Liter box with with 3/4" Sonic barrier on 90% of the walls and additional Acoustistuff both behind the woofers and at the the top and bottom of the (38 inch tall) exclosure.

The note for Physical Vb states: "Add volume displaced by driver, port and bracing to get real construction volume".
I would think they mean subtract driver, port & bracing ??
What about volume dispaced by dampening material ??

I have had Qa entered @ 35 but don't know how close to real world this is ??

Can someone who has a good understanding of these parameters please respond....

Thanks Todd

[Ron E]

A way to put this into perspective is to vary the parameters in question and see how much it affects the outcome. I think you will be pleasantly surprised that it doesn't matter much.

Leave the driver some breathing room with no damping material and as long as you don't stuff the c*r*a*p out of the box and port you will have success.

[djarchow]

I normally just allow the Qa to be set by the Damping drop down.

Regards,

Dennis

[todd95008]

[The note for Physical Vb states: "Add volume displaced by driver, port and bracing to get real construction volume".
I would think they mean subtract driver, port & bracing ??]

This is what I'm most interested in ???

Todd

[Ron E]

Originally posted by todd95008
This is what I'm most interested in ???

Yes they mean subtract from the gross volume of the box...

If you line the box [with damping material], I would put Qa at 20. You can measure impedance after it is complete and vary Qa, Ql and Qp until your impedance curve matches - then you will know the actual Q's