You can't replicate the response of a transmission line with anything other than a transmission line and even then there are variables involved. Other than that, i try to avoid vents of any type as much as possible. If i had to choose out of what is commercially available, i typically prefer sealed low Q designs. Second would be an IB ( Infinite Baffle ) and third would be a stuffed or partially stuffed T-Line. Bringing up the rear in a very distant fourth place would be an aperiodic ( vario-vent ) design. Anything else would be WAY down the list. Sean
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