I do notice port noise when standing at the back. Not audible up front. Mainly from 35 HZ and below starting a couple clicks below full tilt. Since I have the ports next to each other it’s hard to tell which port it’s actually coming from. That’s one downside to this design with ports side by side. With this many bends in the port, I thought it could have a little noise from the port velocity in modeling. I usually account for number of bends in the port and add it to velocity, but the port was already 48 inches long, so I tried to skimp. Since I’m rebuilding it with birch and plexi, I will add another 10% to port area and adjust the overall profile to be a little larger. Its likely from the low tuned port, since the higher tuned port is just one bend, and is far over standard port area per sq. ft.Have you noticed any port noise out of the higher side? I wonder if putting the two ports next to each other like that would help lower port noise?
I do notice port noise when standing at the back. Not audible up front. Mainly from 35 HZ and below starting a couple clicks below full tilt. Since I have the ports next to each other it’s hard to tell which port it’s actually coming from. That’s one downside to this design with ports side by side. With this many bends in the port, I thought it could have a little noise from the port velocity in modeling. I usually account for number of bends in the port and add it to velocity, but the port was already 48 inches long, so I tried to skimp. Since I’m rebuilding it with birch and plexi, I will add another 10% to port area and adjust the overall profile to be a little larger. Its likely from the low tuned port, since the higher tuned port is just one bend, and is far over standard port area per sq. ft.
I will make some small changes for the final enclosure. When I modeled it for the normal ported enclosures I saw some issues with port speeds there also. That’s why i did the port so large on that one. I think I will do kerf cuts and flare the port openings on the final enclosure. I’m very satisfied with the sound I’m getting from it right now. When I did the port calculations I tried to keep the port speeds the same for both front and rear ports, so I sized them accordingly to match each other.Yeah ports start getting long. That’s another benefit of a series 6th is avoiding that too long of port resonance.
I’m not sure if the port noise would come from the high port if say the woofer was extending further or not. I find parallel 6th’s difficult due to the air speeds in the front port, and I’m not sure which port it would be either, not with playing 35 hz and below. A lot of boxes I’ve heard have made slight noise before, but if you can’t hear it up front, I wouldn’t worry about it, unless you have too much power or something.
You could put that high port on the left side, maybe, and just have it L behind the sub. You could also flare those port ends; just a thought.