Roll off vs vent volume in ported enclosures

[Etocynned]

Was debating with someone about how the ratio of vent volume to enclosure volume affects enclosure roll-off below tuning.



He was saying that a larger vent will induce a steeper roll-off for a given tuning due to unreliable impedance interaction.


Is this the case in practice or is he misinformed?

 

[GM]

Just playing with HR, a tiny difference initially, but quickly drops in line with just more gain at Fb. Where we see any significant differences is when comparing BR to BVR, which damps the driver much more.

GM

 

[Etocynned]

thx

 

[TBTL]

The roll-off well below the tuning frequency is 24 dB / octave, regardless of vent or box dimensions.