SI sub?? help

[Kingnoob]

I am getting the SI- 15" sub-woofer , does anyone own this is it better in a Sealed or Ported box for movies
one calc said sealed was best, but most sites say ported have higher Spl

Can a 500w Rms bash amp power it well? or do you know a cheaper better amp for the price
This ampBash 500W Digital Subwoofer Amplifier 300-752

 

[Inductor]

Do you mean this?
Stereo Integrity HT 15" Subwoofer

It works nicely in a bass reflex system, also sealed.
I advise you to use a VB = 130.5 L tunned to FB = 16.9 Hz. F3 is 25 Hz (19Hz in room).
Sealed system has F3~42Hz, so much different.

but most sites say ported have higher Spl

Sensitivity it's the same.
Max SPL
Ported: 1.00 m 121.5 dB (V=98.92 V, Pmin ~2057.6 W/4.8 Ohms/103.5 Hz)
Sealed: 1.00 m 114.2 dB (V=42.73 V, Pmin 493.6 W/4 Ohms)

 

[m R g S r]

Go on hometheatershack.com. Check out the DIY subwoofer section. People love the SI subs....for The price they're great.

 

[Kingnoob]

which calculator is the best for DIY subwoofers??
The only thing that confuses me is how you wire this speaker to the bash amp?

 

[Inductor]

...how you wire this speaker

Is that a problem?

 

[Inductor]

Do you know how to use WinISD? others?
UniBox - Unified Box Model for Loudspeaker Design

 

[Kingnoob]

Is that a problem?

Yes ! Exactly the problem I need help with that....

 

[Kingnoob]

wiring the SI Subwoofer to the bash amp is confusing.
What is better D2 model , or D4 sub
2+2 ohms = 4ohm in series I think.

So I should get the 2 ohm per coil version probably??

 

[Inductor]

3 questions.

1st - With a 4 ohm amp I would want to buy the Stereo integrity 2+2 ohm per coil woofer right??

2nd- I want to know how to wire in Series this DVC sub-woofer for 4ohm to run with the bash-500 amp

3rd- Which amp would you suggest? To power Stereo integrity HT 15" Dual 2 Ohm subwoofer.

I don't know if the PM went trough or not so again,
The 500w rms bash amp is knowed as a very best in it's class by this forum. Others diy'ers can give you more references in what amp to choose.

2+2 Ohm DVC vs. 8+8 Ohm DVC
"2+2 ohms = 4 ohm in series",
or a 8+8 Ohm DVC (paralel), both are good for a 4 Ohm amp.
(In case you have a 4+4 Ohm DVC just connect one coil and will be fine.)

How to connect one DVC?
All speaker drivers are different, but all connections are almost identical.
Please refer to a printed pic.
http://stereointegrity.com/docs/DVCwiring.pdf

1. DVC wiring. For a dual 8 ohm voice coil drivers in parallel (4 Ohm)
2. DVC wiring. For a dual 2 ohm voice coil drivers in series (4 Ohm)

 

[Kingnoob]

SO buying a 4+4 ohm Voice coil and hooking one coil up would give the Sub-woofer full power correct?
Or does a 2+2 series sound better, and deliver more power?

Now all I need to know is what sized Port I will need Ill look at calculators I guess.
Thanks

 

[Kingnoob]

2+2 series would handle more power... Kicker site helped alsohttp://www.kicker.com/dvc_wiring

What is the proper port size for a 130.5 liter box tuned to 16.9hz?

 

[Inductor]

What is the proper port size for a 130.5 liter box tuned to 16.9hz?

You can play with that. Do you want circular port holes (tube) or rectangular. If one or the other; what are internal diameter (circular) or width x height (rectangular).
You can simulate that in the software. I don't mind you ask that question to the forum (also). Example, say for circular ports:

2 circular ports
int. diam. 9.4 cm (3 3/4")
length 102 cm (40")

same for 1x rectangular port/vent with HxWxL,
5 cm x 30 cm x 89 cm (2"x12"x35")

So as you see it needs to be adapted to the enclosure you have, lets say max length will give the internal max length of the tube or tubes (circular or rectangular).
Width will define one or the other of the dimensions of a rectangular port.

 

[Kingnoob]

circular ports.
Would a 5cu feet box require shorter port's??
How long for 4" ports?

Parts express has 4" ports decent priced Precision Port 4" Flared Port Tube Kit 268-352

 

[Kingnoob]

whats the sound quality? Bass difference between Ported/ sealed
I have a 12.5 foot x 13 foot bedroom for sub.

Id prefer circular ports from Parts Express.com
would using a larger port / Larger box .. make port Length required shorter?

 

[Inductor]

whats the sound quality? Bass difference between Ported/ sealed
I have a 12.5 foot x 13 foot bedroom for sub.

Id prefer circular ports from Parts Express.com
would using a larger port / Larger box .. make port Length required shorter?

Larger port requires longer tubes.
Sealed vs. Ported

 

[Inductor]

circular ports.
Would a 5cu feet box require shorter port's??
How long for 4" ports?

Parts express has 4" ports decent priced Precision Port 4" Flared Port Tube Kit 268-352

You might look at sealed because of the ports.
17in = 43.180cm
Parts-express PORTS 17" long in 2", 3", and 6" diameters are to small in lenght.
The problem with small diameter is the air speed noise at max output SPL.

 

[Kingnoob]

Sealed would make things easier except how expensive is the acoustic stuffing??
Poly-fill or some sort?
How much Poly fill would I need Acousta-Stuf Polyfill 1 lb. Bag 260-317
a 3-4 cu foot box is recommended for sealed.

thanks,
kingnoob

 

[Inductor]

Another project with pictures in a sealed 2.7ft³ = 76.455L. (Forum referenced by m R g S r)
Another Stereo Integrity Build, HT-15D2 - Home Theater Forum and Systems - HomeTheaterShack.com

 

[Kingnoob]

Another project with pictures in a sealed 2.7ft³ = 76.455L. (Forum referenced by m R g S r)
Another Stereo Integrity Build, HT-15D2 - Home Theater Forum and Systems - HomeTheaterShack.com

I take it a 2.7-4 cu feet sealed sub would do excellent
Yes I have seen this thread many times while googling , I take it he dosn't use plate amps for sub's?

Is bracing always a plus when using MDF?

 

[Kingnoob]

Do larger sealed box'es hit low notes better? Or smaller ones

I plan on adding poly-fill so my Sealed sub has more authority & less Resonant noise too