Hi,
I've built a 38-liter port speaker to be tuned to 28Hz.
Using default WinISD end port correction of 0.73 I've got a theoretical 16cm port length for a non flared 5cm port diameter (I know it's small but this speaker is for low power levels). Checking the real built box, I've got the tuning well below 28Hz.
Searching the forum, I've got a picture set that indicates that when we share walls with the port, the end port correction increases.
I my case, I have a round port pipe but it is very close to 2 walls - the pipe is only 1cm away from the walls. See pictures below.
Question: should the end port correction be something between 0.73 and 1.7, as shown in the picture set below?
From my tests, I shortened the pipe to 11cm to get the planned tuning. With 11cm the simulation factor should be 1.7.
I'll adjust to my needs, but I just want to understand what happened and if this is really due to the port being very close to the walls.
Thank you!
Pictures of my box port.
I've built a 38-liter port speaker to be tuned to 28Hz.
Using default WinISD end port correction of 0.73 I've got a theoretical 16cm port length for a non flared 5cm port diameter (I know it's small but this speaker is for low power levels). Checking the real built box, I've got the tuning well below 28Hz.
Searching the forum, I've got a picture set that indicates that when we share walls with the port, the end port correction increases.
I my case, I have a round port pipe but it is very close to 2 walls - the pipe is only 1cm away from the walls. See pictures below.
Question: should the end port correction be something between 0.73 and 1.7, as shown in the picture set below?
From my tests, I shortened the pipe to 11cm to get the planned tuning. With 11cm the simulation factor should be 1.7.
I'll adjust to my needs, but I just want to understand what happened and if this is really due to the port being very close to the walls.
Thank you!
Pictures of my box port.
Yes, most probably!
Your port layout seems very similar to the square port in the enclosure corner.
Hi,
Yes, the proximity to those walls in that corner like that will put the end correction factor closer to 0.8~1.2 range probably. But yes, placement matters relative to the enclosure walls.
WinISD doesn't do port length correctly on end correction values other than 0.732, so it will always give an incorrect length if the actual end-correction is anything other than 0.732 (change the number in the software and the length doesn't change).
Very best,
Yes, the proximity to those walls in that corner like that will put the end correction factor closer to 0.8~1.2 range probably. But yes, placement matters relative to the enclosure walls.
WinISD doesn't do port length correctly on end correction values other than 0.732, so it will always give an incorrect length if the actual end-correction is anything other than 0.732 (change the number in the software and the length doesn't change).
Very best,