Current dual-opposed sealed build with these drivers:

https://www.avsforum.com/forum/155-di...-21-build.html


I'm currently building 8 of these:

Outside dimensions with double baffle:

36" wide
28.5" tall
30" deep

(3) 8.5" x 2.625" ports. Port length is ~55".

Net internal volume: 11.72cu.ft













1/2" round over:

















Tune came in at 14hz:





All 8 + the Othorns stacked behind the mains:

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T/S specs for the drivers. I will add...I didn't secure/bolt down the driver when getting these parameters, and Ricci told me that will cause the BL to come in a little lower.


Re = 2.8983 ohms
Fs = 31.2837 Hz
Zmax = 64.4377 ohms
Qes = 0.5802
Qms = 12.3192
Qts = 0.5541
Le = 4.2938 mH (at 1 kHz)
Diam = 454.1638 mm ( 17.8805 in )
Sd = 162000.0005 mm^2(251.1005 in^2)
Vas = 142.7929 L ( 5.0427 ft^3)
BL = 25.7591 N/A
Mms = 675.7605 g
Cms = 38.3012 uM/N
Kms = 26108.8594 N/M
Rms = 10.7822 R mechanical
Efficiency = 0.7080 %
Sensitivity= 90.5184 dB @1W/1m
Sensitivity= 94.9278 dB @2.83Vrms/1m
Krm = 28.598E-03 ohms Freq dependent resistance
Erm = 784.948E-03 Rem=Krm*(2*pi*f)^Erm
Kxm = 272.943E-03 Henries Freq dependent reactance
Exm = 525.888E-03 Xem=Kxm*(2*pi*f)^Exm
;------------------------------------------------------------------
Ftest = 25.919 Hz
Ftest/Fms = 0.8285
Test Mass used = 308.6900 g (Equal to 61.7 nickels)
Test Mass (Ft=Fms*0.90) = 158.512 g (Add -150.178g for Ft=28.155)
Test Mass (Ft=Fms*0.75) = 525.592 g (Add 216.901g for Ft=23.463)

Two are done and I'm applying the Duratex, and @dsl1 CNC cut the baffles for the remaining 6 boxes.

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Wow 8 of these, your room is going to be insane. The bracing looks great in the cabinet. Subscribed

Initial SPL testing with one cab indicates that with all 8 I'll be approaching 148-150db from 15-20hz!

Looking good Luke! I can't wait to come up and hear them.

How big is your room?

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Will be fun watching this come together. Subscribed.

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Just WOW!!!

About 2,300cu.ft. 12'x23' with 8ft ceilings.

Same size as mine. I've got two 21s, and it thumps pretty good in there. 8 is just mind blowing...

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Two of these ported is producing more SPL from 12-20hz than all 8 could sealed.

These cross over to dual Othorns at around 30hz, so once these ported boxes are finished I'll be around 145db from 14-150hz:




Most I've hit in the room at the LP so far (I use the "max" value so I consider this 147db):

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Not sure if that's the correct question


How close are your neighbors?

Fortunately for me my HT is completely below ground level. You can hear it outside (mostly noises from my house rattling) but I doubt you can hear it once inside one of the neighbors houses.

Lmao. I bet it's heard quite further than you would think especially at night when all is quiet.

Crazy bastard!

gotta see this ............

10 if you count Luke's two iPals in the Othorns.

It was crazy in there with the 21s sealed, in these monsters....well I'm really looking forward to demo clips. Especially some of the lower stuff.

"OK guys I'll turn it up for a demo, hang on..."

Your builds make me happy.

In the past I have asked my neighbors if they heard anything, and they hadn't, but after this build I may have to inquire again

I have awesome neighbors, so even if they did occasionally hear something I doubt they'd care.

Is this still a thing?

I would have thought you would have moved on to passive radiators by now.

Been there done that

Besides the extra cost I really liked the dual PR sub!

This is just plain UNFAIR.. Like Really Unfair.. WHY? WHY? ... Yes I'm Jealous..

I vibrate my neighbors house so don't assume.

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Subed... all pun intended.

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Please delete duplicate

LMAO

your going to have to worry about stuff falling off of their walls and shelves. been there, done that. "that" they will not like.

i used to live in an all concrete condo, ceiling, walls, floor. it had room gain like you would not believe. i would crank it up LOUD = anyone on this forum would be proud. only towards the end of me living there did i get any "feedback", lol. that was 1 reason i moved.

"Hi. My name is Luke and I have found the brown note."

Time to check your home insurance policy!