Bandpass Question

[jwatts]

I am having a difficult time designing a bandpass box because the ports are to long and won’t fit inside the enclosure. My question is this. If I can preserve the front and back enclosure volume ratios can I simple multiply both by a factor and make them larger. The enclosure is a 4th order bandpass.

Example.

Assume was originally calculated to be.

Vf=.3ft^3
Vr=.5ft^3

Can I simply multiply both Vf and Vr by 3 and not change my passband, ripple, and Fb for the enclosure.

 

[lndm]

To make a vent shorter, you could make it narrower. Still, try to keep it as wide as possible. A really long vent can cause resonance problems anyway.

Have you considered mounting the vent outside the box?

 

[jwatts]

Impractical

My current application will not allow me to vent outside of the enclosure.

 

[Ron E]

Can I simply multiply both Vf and Vr by 3 and not change my passband, ripple, and Fb for the enclosure.

No. Use a PR.

 

[Jonathan Bright]

Is there any possibility of bending the ports inside the enclosure?If you use plasitc pipe the purchase of 90 degree joints etc is v.easy.

 

[jwatts]

Pr

Does anybody have any experience using a PR in this type of application? If so does perform as well as a port.