Ported EBS sub alignment-please vote

[masterp2]

Which of these alignments would produce more robust, clean, flat performance, mostly for HT. It will be a non-corner-loaded application. Sub will be located behind sofa. Up to 1000W available. Disregard port constraints. They are not an issue. Only ported suggestions, please.

volume,Fb
a.)140l, 22HZ
b.)160l, 20HZ
b.)180l, 20HZ
c.)220l, 18HZ
e.)"here's my suggestion"


Driver is an HE-15


Qts .326
VAS 3.768ft^3
Fs 29
Re 1.5 Ohm DVC
Le 3.7
xmax .9 inches, 23 mm
Z 2.0 Ohm
Qms 6.0
Qes .345
SPL 89.42
Pe 2000W
Bl 13.5
Dd 11.92
Sd 740cm^2, 111.6 in^2

Thank you to all who model it.

[sreten]

IMO there's not much point going beyond the Vas of the
driver for the box volume ever, if there is it's a poor driver.

The white curve is what I'd suggest.

sreten.

[sreten]

100litre alignments, sreten.

[roddyama]

I kind of like the blue curve in both cases. It seems to be a good compromise between BW extension and damping.

[masterp2]

OK, I walked straight into that. Hold on! I mistated. I DO have port constraints, and they are going to require a volume of at least 140 l at these Fb's.

So nothing under 140l, and nothing tuned over 24HZ, sorry.

Again, will not be on a wall or corner, just direct radiating.

Thanks

[masterp2]

Oh yes, I forgot to say thank you Sreten.

[masterp2]

Here are the ideas I am working with. These are constrained by my max port length. Again no boundaries within 5 feet of the sub.

[masterp2]

Same alignments, with mass added, 25-100g. Would this be a viable option? Pros, Cons?

Please give an opinion

[sreten]

JMO but I'm into alignments that support room gain and are
tuned to interface with room modes. As room modes are 1/2
wavelenth = room length you can easily work them out.

v sound =1120ft/s, consider a room 20ft x 14ft x 9 ft.

1st modes are 28, 40, and 63 Hz, a nicely shaped room.
(Double them , they don't overlap then triple....)

In this case at slight dip around 28Hz and a peak below
28 Hz, at around 20Hz will work well with the room.

For smaller speakers a port tuning of around 33Hz would
work well with this room, the 28Hz mode defining the cutoff.

Port frequencies of around 28 Hz and 40Hz should be
avoided in this room.

I'd say your 180/19 would work best in this room.

sreten.

[masterp2]

My port and driver size limit box volume to a minimum of 150 l, maybe 140l.