Spec me, please!

[BigDaddy13440 3]

Before I yank my existing Celestion AD15H's, I'm going to try and change the porting, see if it cleans up the sound a bit. I think I'm getting excessive port turbulence, want to increase the diameter of the port to 4" from the existing 3".

The specs for the AD15H's:

Size : 15"

Mag dia: 8.5"

Mag Structure wt: 367oz

Mag wt: 126oz

Voice Coil: 4" dia

Former: Kapton

Coil winding length: .63"

Magnet gap depth: .374"

Coil: Copper

Coil Section: Round

Overall depth: 6.7"

Weight: 28.48lbs

Freq resp: 30-1K

Max X-over Freq: 500Hz

Sens (1W@1m): 96

Power handling: 1200 peak, 600 cont

Nom Imp: 4 ohms

Resonance (fs): 29Hz

Resistance (Re): 2.8 ohms

Piston dia (d): 12.99"

Piston area (Sd): 132.53"

Vas: 7.4 cu ft

Total Dyn Mass (Mmt): 129gms

Elect Q (Qes): .271

Mech Q (Qms): 5.890

Total Q (Qts): .260

Bl product (Bl): 16.34Tm

Peak excursion: .157" (only 4mm!)

Flux density (B): 1.33T

Coil Inductanc @ 1kHz (Le): 1.6mH

Recommended Alignments:

1.55 cu ft, 3" port x 11.46" long, tuned to 30Hz

2.12 cu ft, 3" port x 7.79" long, tuned to 30Hz

My current enclosure(s) are approximately 2.25 cu ft, with a 3" port x 8" long. I'm looking to go with a 4" port (for less turbulence), but would like to know if a different tuning frequency would give me clearer, tighter bass for the specifications given. A 4" port tuned to 30Hz is 14.86" long (for 2.12cu ft), whereas a 32Hz port is 12.67", and a 34Hz port is 10.89" - big difference between 30Hz and 34Hz.

[JBerger 0]

What kind of music are you listening to mostly?

[BigDaddy13440 3]

What kind of music are you listening to mostly?

Wide range, from Alter Bridge to ZZ Top, Metallica to Aerosmith.

Not a lot of rap/hip-hop, but I do have some old 2Pac and Dre in the MP3 files. Have some old-school DJ Magic Mike too, but I might break that out maybe once every 3 months, just don't listen to that type of music anymore.

[JBerger 0]

If you use your current enclosure at 2.25cuft, than you need a 4 inch port thats about 5 5/8" long which will give you a bit higher tuning to about 42hz. This will be more suitable to what you listen to.

[BigDaddy13440 3]

If you use your current enclosure at 2.25cuft, than you need a 4 inch port thats about 5 5/8" long which will give you a bit higher tuning to about 42hz. This will be more suitable to what you listen to.

I take it that those specs would indicate more output in the 40-50Hz range with the 42Hz tuning frequency?

Won't the power handling on anything below 40Hz or so plummet like a rock? I'm guessing a subsonic filter set at 38-40Hz would be appropriate?

[JBerger 0]

I'd set the sub sonic for 20hz and set the x over to around 80hz