[Aural_Sex]

I'm playing with a box design for some end tables with the UM18-22's; however, I'm running into issues with the port tuning where the ports look crazy long. If I lower the diameter it length becomes reasonable but they don't meet the BassBox "Minimum Vent Area for Xmax". I'd like to get some eyes on it to see where I'm going wrong. I've attached my BassBox and WINISD files. Cheers!

View attachment Dayton 18 End Table 8-7-2019.zip

View attachment Dayton UM18-22 End Table 8-7-2019.zip

 

[johnson636]

I don't have Bass Box, but the graphs in winisd look about right. What dimensions did you have in mind?

 

[Aural_Sex]

I'm looking at 24x24x29 - when I calculate the minimum vent area it puts my length at 56" which would be a bit of a challenge unless I stack the port.

 

[Zarkoff500]

How does port velocity look? Lower is better but I think 22-24 m/s is acceptable.

 

[lknhomeaudio]

How does port velocity look? Lower is better but I think 22-24 m/s is acceptable.

With 62 sqaure inches of port area, it can't be too high! That's the equivalent of nearly a 9 inch round port.

 

[Aural_Sex]

With the suggested minimum vent area (2.6x26) it's incredibly low - .155 m/s - I must be missing something. Any idea how BassBox calculates the minimum area?

 

[Aural_Sex]

With 62 sqaure inches of port area, it can't be too high! That's the equivalent of nearly a 9 inch round port.

Exactly this - I'm not sure how it calculates the minimum vent area for xmax but that seems like an insane area, which appears to be driving the crazy port lengths.

 

[lknhomeaudio]

Just shrink it down to something respectable. And doable lol... 15-20 m/s is decent.

 

[Augerhandle]

What's your High Pass setting? If you move it slightly higher to even out the excursion humps in the graph, you'll be able to apply more power, and thus get a bit more SPL.

 

[johnson636]

^^^^^^^^^He used a 15Hz hpf

 

[Augerhandle]

^^^^^^^^^He used a 15Hz hpf

Never saw that. Maybe it's in the zip file I never opened?

 

[johnson636]

Maybe it's in the zip file I never opened?

Yup

 

[Augerhandle]

It figures. I don't open zip files from anyone with less than 2400 posts.

 

[lknhomeaudio]

I never do!

 

[Aural_Sex]

It figures. I don't open zip files from anyone with less than 2400 posts.

Only 2369 to go!

 

[Aural_Sex]

Anyone know the port area and length of the marty cube for comparison?

EDIT: 2368