BBLV

On 10/25/2019 at 11:19 AM, dgage said:

My commercial subs are just under 9 cf with 4,000w continuous and like I said, flat to 7 Hz with a Linkwitz Transform and room gain.  So 10-12cf should give you plenty of low-end output but not as much above 40 as if you went ported but the 40+ Hz would really only be usable in venues as they’d be too loud for a home theater in my opinion.  So the sealed 10-12 cf is straight forward and a proven performer while not being TOO big.

Decided to go 12cf sealed... I'm using the SpeakerPower SP2-12000-DP.

Just started my theater build thread over at AVS, but here are the details for my SHS-24 enclosures:

SI SHS-24 Sealed Enclosures (x2):
- Overall Dimensions: 37.75”H x 37.75”W x 21”D
- 12cf internal volume
- 1” MDF double baffle and exterior panels with ¼” rabbets
- ¾” MDF bracing

Thanks for the inspiration @Ricci !

Here are WinISD max SPL and cone excursion plots of sealed enclosures at 4cf, 10cf and 12cf with 6000w of input for comparison's sake.

2 minutes ago, dgage said:

No way the 24 would work well in 3 cf, my guess is you’re getting the 18. Infused as that works well in 3-4 cf.  for the 24, I wouldn’t go smaller than 8 cf and you do get a little lower extension going 10-12 cf, which would be my recommendation.  Then again, I usually recommend to my customers multiple 18s over a single 24 for more even bass response in the room. It I think you already have the 24s.

Yes, I already have two dual 1-ohm SHS-24's sitting here begging to crack my triple layered drywall 😎

Regarding a sealed enclosure, I've seen mention of 3cf but feel that would just be awkward in my theater room. Do I lose anything going to ~10-12cf sealed?

1 hour ago, Ricci said:

Hey man...Unfortunately what you would be building would be nothing like the winisd sim...

Good looking out! 😂 I owe you a beer (or three).

I'm not very experienced in the model vs real world translation, so I guess I'll sit by and wait for more details on your enclosure and build accordingly in the 15cf range. The last thing I want to do is to spend the time and effort building these boxes and them sound like shit.

FYI mine are dual 1 ohm coils and will be running on an SP2-12000 amp. I'm using the T/S parameters emailed directly to me from Nick for WinISD. I've modeled the following ginormous enclosure for each sub. These will be against the back wall of my 17.5'W x 26'D x 9'H dedicated theater room where the cone will be about 5' behind the back row of seats and 10' behind the front row. The plan is for these to handle ~10 to 45Hz where my LCR speakers will takeover (DIYSG dual woofer Titans).

• Box: 30cf @ 12Hz
• Vent: 30"W x 4.5"H x 66.5"L
• 1st Port Res: 96.93Hz
• Rear Port Air Velocity: ~29.5 m/s max @ 11.5Hz
• Cone Excursion: 36.6mm @ 10.4Hz
• Filter: HP BW4 @ 11Hz
• Input Power: 6000w

I was trying to increase the port area to lower the port velocity and increase SPL/cone excursion, but the 1st port resonance was dropping too low for comfort. I think this is a decent happy medium - I'd obviously love to get a little more SPL and utilize ~10mm more xmax. Thoughts on how to get there without creating port chuffing/resonance issues?

@Ricci Did you ever design and/or build enclosures for these? I have two sitting here waiting for time to start cutting wood and was hoping to compare notes.