SS15 or Tham 15?

[djk]

I'm looking at the minima at 28hz and 36hz, that's determined by how long the TH is.

Do you really think it's the driver?

[Djim]

Originally Posted by djk

Do you really think it's the driver?

If that is true the driver has a significant modification.

[weltersys]

Originally Posted by djk

I'm looking at the minima at 28hz and 36hz, that's determined by how long the TH is.

Do you really think it's the driver?

I was looking at the minima as well in a simulation, it is easier to see the LF maxima, which was lower for a 15 than an 18.

It seems odd that they would be like 10 Hz apart, rather than about 3 Hz different.
It is probable that the "V" throat stub on the much larger volume 18" changes things rather than the minimal path length difference, as the 18" version would be slightly shorter.

That said, I am more interested in FR than impedance curves, the TH-118 goes lower and louder than the TH-115 in the same size box.