hey everyone i was just wondering what determines a slot ported box's tuned frequency. i know it is the box volume and port volume but i was wondering if port length or width or height matter, or just its overall volume.
for example if i have two ported boxes with the same volume and same port volume, but one port is longer in length but shorter in width, and the other is shorter in length, but longer in width, would the tunning frequency be the same or not? thanks!
It all plays a part. Too narrow a port and you risk port noise. It's a calculation that includes all three parameters.
In your example, it's all about moving air. Kind of like a valve. Open wide the flow rate is large and velocity is low. With the same pressure (air, water, whatever) in a valve closed slightly the velocity MUST increase to maintain the same volume of (air, water, whatever) coming out. Generally you want to avoid small port parameters of any size to avoid the increased port velocity (risk of noise). After all, that air is being forced out that port by the diver one way or the other. With port area being equal you will indeed change tuning by adjusting depth.
Port area is height X width. Port volume is height X width X depth. Changing any one of those will affect tuning.
