Porting the mid if you have a woofer?

The mid ai plan on using has a .13 sealed requirement, which is tiny but I want a bigger box.

If I go to .25 then that would be better, but it’s ported and it brought up the question should you port the mid If you have a woofer?
 
6.5" mid, woofer is 12" they are in separate cabinets so there is no air exchange in the enclosure, I was just wondering about tuning 2 ports vs just having the woofer and if porting the mid by itself posed any danger or presented any benefits. I don't see it alot.
 
Not very common but it has been done, in that case for good reason.

Electro Voice did it in a PA cabinet intended for very high SPL , and which became the favourite of a few Top Notch Bass Players.

EV VMR (Vented Mid Range)
Sporting a monster (for a midrange) 2.5" edgewound aluminum ribbon voice coil and
"This optimally vented midrange uses exactly the same 16-pound magnetic structure as the woofer...."
and not "any" woofer but an EVM12L

A beast among beasts.

3015551-73b21652-electro-voice-vmr-vented-midrange-driver.jpg


3015549-54190321-electro-voice-vmr-vented-midrange-driver.jpg


656001284e53bd234abbca2461dc
 
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Its not that it 'has' to be ported its just what is suggested.
who suggests it?
maybe it's suggested if you use the driver as midwoofer and need increased bass response (without added woofer).
anyhow, as pop4richard wrote we would need more information to give good answers:
what midrange and woofer do you plan to use?
what is the planned crossover frequency to the woofer?
what SPL do you expect or need?
 
if the highpass the mid is passive and odd order then there's potential problems of the lower Z peak interacting with the capacitor's reactance to create a "boost" and added/unwanted excursion. I do think someone like Irving Fried would use a couple of "pressure-release" holes. (Those VMR used about the same motor as EV15L !)
 
I should have said either - both of the reflex peaks could cause trouble.

Here's my lone VMR (not iots picture)- it had just be re-coned so perhaps H3 would have dropped ? - also, there was no damping material in the pan
 

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I have tinkered quite a bit with ported midbass for car audio and created ported door pods for my wifes car.

For a low Qts driver like your Morel I would put it in a QB5 alignment, larger box but lower excursion at the expense of slightly less low end extension.

QB5 alignment


What frequency do you intend to high pass the midbass? If it is high enough, you won't get much if any benefit from the port.