What port diameter to choose

[Troy Bakker]

Hi,

I am planning on building a subwoofer box for my home theater with a digital designs dd506d2
The design will be a double reflex chamber tuned between 20-25hz with one chamber around 5 liters of volume and the other one around 20.

I have a question about what my port diameter should be:
I was thinking about 65mm the port will be 1 meter long this way (which is fine) and the air velocity at 100 watts will hit the 17m/s mark

A the moment i have a 8 inch infinity subwoofer with a port thats 50mm in diameter. This subwoofer has noticeable port noice/chuffing. So I dont know if a 65mm port will be big enough in diameter (the surface area of this 65mm port is almost double of the 50mm port)

Any comments would be highly appreciated

 

[Troy Bakker]

Other information that can help me is telling me how big of a room i can fill with 60-70 watts of power which should make around 95db

 

[GM]

Greets!

Well, wrote up misc. details with modded Hornresp sim and forgot to factor in the requisite band-pass filters, so will have to redo as time permits since it will make a significant difference re vent design. 🙁

 

[Rademakers]

17 m/sec is a good upper limit for casual listening.

 

[Troy Bakker]

17 m/sec is a good upper limit for casual listening.

I have read that before. and the program i use (vituixcad) shows 17m/s as turbulence warning and around 30m/s as turbulence limit. But I put the 8cm diameter in the program flare-it it sais that port compression will become a thing under 15m/s