T section ports and helmholtz resonance question

[mondogenerator]

can anyone advise me regarding port behavior in a T-section port, with each arm of the port vented externally and the vertical part of the T into the enclosure? obviously it depends if the internal and external 'ends' of the vent have equal CSA, so in that case does it act like a conventional port duct? or does it need to be twice as long?

[mondogenerator]

rather should i say 'T shaped' rather than T-section....

[Ron E]

Originally Posted by mondogenerator

can anyone advise me regarding port behavior in a T-section port, with each arm of the port vented externally and the vertical part of the T into the enclosure? obviously it depends if the internal and external 'ends' of the vent have equal CSA, so in that case does it act like a conventional port duct? or does it need to be twice as long?

Draw a line where you would fold it in half. Design as 2 ports with 90 degree bends.

[mondogenerator]

Thanks Ron, that was my first thought, but i was uncertain in my assumption.

Im thinking of a port extending between the left and right hand sides of the box, perhaps with just a hole midway along to the pipe of equal CSA the the total external vent area--similar to a flute mouthpiece i guess....probably should have made the leap and realised myself