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PSturmer
04-26-2008, 11:44 PM
i was wondering if you had 2 4'' aeros of different lengths in the same box how this affects spl and how to calculate tuning frequency.

thanks

mapolley07
04-26-2008, 11:46 PM
why in the hell would you want to do that?

IgnoreMe
04-26-2008, 11:47 PM
i was wondering if you had 2 4'' aeros of different lengths in the same box how this affects spl and how to calculate tuning frequency.

thanks

it probably wouldnt help. but why not just try it?

i wouldnt, but if you got the time why the **** not. just make sure and say you were baked as hell when you thought/did this so you have a cop out when **** hits the fan

PSturmer
04-26-2008, 11:49 PM
i dont have access to a band saw untill monday so i have to use the ports i have already.

mapolley07
04-26-2008, 11:55 PM
i dont have access to a band saw untill monday so i have to use the ports i have already.

then wait until monday :rolleyes:

you can also use a hack saw or a chop saw if need be

bigbang
04-27-2008, 09:10 PM
In theory the shorter port would have a smaller air mass than the longer port, therebye offering less resistance and being tuned higher. This shorter port would be unloading at the lower frequencies that the longer port would be tuned for, rendering the long port's tuning range useless. If the longer port was substantially longer, it might have enough air mass that it would not effect the shorter ports tuning range, acting as if the longer port were alltogether not present, so the short port could do its job at the higher tunning. But this is unlikely the case, and pointless if executed.

In the case that the length of the two ports is very similar, the overall tuning of the system will take on the characteristics of the shorter port, but when playing frequencies below the shorter ports tuning range, the short port will unload first and more easily than the long one, and therefore generate more port noise, wind, ect than the longer one would.

The only time port lengths should differ is when port diameter differ also e.g. mixing a 3" and 4" diameter port.

IDSkoT
04-28-2008, 01:42 AM
In theory the shorter port would have a smaller air mass than the longer port, therebye offering less resistance and being tuned higher. This shorter port would be unloading at the lower frequencies that the longer port would be tuned for, rendering the long port's tuning range useless. If the longer port was substantially longer, it might have enough air mass that it would not effect the shorter ports tuning range, acting as if the longer port were alltogether not present, so the short port could do its job at the higher tunning. But this is unlikely the case, and pointless if executed.

In the case that the length of the two ports is very similar, the overall tuning of the system will take on the characteristics of the shorter port, but when playing frequencies below the shorter ports tuning range, the short port will unload first and more easily than the long one, and therefore generate more port noise, wind, ect than the longer one would.

The only time port lengths should differ is when port diameter differ also e.g. mixing a 3" and 4" diameter port.

:word: