Going Infinite Baffle, What 15 or 18 is good?

[Dtour 10+ year member]

I have a 03 civic 4 dr, I want to go IB and wondering which drivers will sound great, any advice is welcome

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[Immacomputer 10+ year member]

Look for something with a Qts higher than ~.5 or so and a low Fs (lower than about 28hz). Those two things will help you find a woofer that will get low and should sound very nice.

The Qts value of the sub will be your Qtc value and it will be the alignment that you will be left with if it is a true IB system.

 

[Dtour 10+ year member]

what about a qts of .37 and a Fs of 20hz?

 

[req 5,000+ posts]

he said higher than .5 man. but that fs is right.

is that the aura one?

but then again, the idq has a qts of .25 and a fs of 20hz. so it might work well. those numbers are just rules of thumb that make any driver sutible for this application.

 

[hayden 10+ year member]

Q series from Fi. Scott will make adjustments to them so that they are perfect IB drivers. He as done this for numerous HT guys. You can also get a killer deal on four of them.

JP

 

[Immacomputer 10+ year member]

what about a qts of .37 and a Fs of 20hz?

It can work, just like the IDQs and it will probably get pretty low with that Fs. What subs are you looking at? Other parameters do matter as well and just looking at Qts and Fs is kind of over generalizing.

 

[Dtour 10+ year member]

Aura Sound

NS15-992-4A

Nominal Diameter . . . . . . . . . . . . . . .15 inches (393 mm)

Nominal Impedance (Z) . . . . . . . . . . 4 Ohms

Sensitivity, 1W/1m (E) . . . . . . . . . . . 86 dB @ 100 Hz

Power Capacity, RMS (Pe) . . . . . . . . 800 W

Power Capacity, Peak . . . . . . . . . . . 3200 W

Frequency Range (-10dB) . . . . . . . . Fo - 1.5 kHz

Minimum Impedance . . . . . . . . . . . . 5 ohms

Voice Coil Diameter . . . . . . . . . . . . . 99.2 mm

Voice Coil Winding Length (h) . . . . . 25.4 mm

Voice Coil Number of Layers . . . . 1

Voice Coil Former Material . . . . . . . . Glass composite

Voice Coil Wire Composition . . . . . . Aluminum Ribbon

Magnetic Material . . . . . . . . . . . . . . Neodymium radial

Stray Flux Shielding . . . . . . . . . . . . . Inherent

Magnetic Gap Depth (He) . . . . . . . . 50.8 mm

Cone Material . . . . . . . . . . . . . . . . . Aluminum

Surround Material . . . . . . . . . . . . . . Injecton molded rubber

Polarity, Outward Motion . . . . . . . . . Positive voltage on (+) terminal

Net Weight . . . . . . . . . . . . . . . . . . . . 20.1 kg

Thiele / Small Parameters

Resonant Frequency (Fo) - Fs . . . . . 20 Hertz

Voice Coil DC Resistance - Re . . . . . 3.3 ohms

Total Q - Qts . . . . . . . . . . . . . . . . . . 0.37

Mechanical Q - Qms . . . . . . . . . . . . 8.0

Electrical Q - Qes . . . . . . . . . . . . . . 0.40

Equivalent Volume of Air - Vas . . . . . 169 L

Radiating Piston Area - Sd . . . . . . . . 765 cm 2

Electrical / Mechanical Parameters

Flux Density x Length - BL . . . . . . . . 18 Tesla-meters

Compliance - Cms . . . . . . . . . . . . . . 206 mm/N

Total Mass - Mms . . . . . . . . . . . . . . 314 grams

Impedance

Frequency Response (1W, 1m)

Maximum Excursion . . . . . . . . . . . . . 75 mm peak to peak

Xmax . . . . . . . . . . . . . . . . . . . . . . . . 38 mm peak to peak

Distortion (1W, 1m)

I purchased one last night, read a ton of reviews and have yet to find anything negative about them, these ar used in Wilson Audio cabs

 

[Immacomputer 10+ year member]

Actually, yes, I think those would work out very well in an IB environment. They should get pretty low and should be very smooth sounding.

 

[IamDeMan 5,000+ posts]

Aura Sound
NS15-992-4A

Nominal Diameter . . . . . . . . . . . . . . .15 inches (393 mm)

Nominal Impedance (Z) . . . . . . . . . . 4 Ohms

Sensitivity, 1W/1m (E) . . . . . . . . . . . 86 dB @ 100 Hz

Power Capacity, RMS (Pe) . . . . . . . . 800 W

Power Capacity, Peak . . . . . . . . . . . 3200 W

Frequency Range (-10dB) . . . . . . . . Fo - 1.5 kHz

Minimum Impedance . . . . . . . . . . . . 5 ohms

Voice Coil Diameter . . . . . . . . . . . . . 99.2 mm

Voice Coil Winding Length (h) . . . . . 25.4 mm

Voice Coil Number of Layers . . . . 1

Voice Coil Former Material . . . . . . . . Glass composite

Voice Coil Wire Composition . . . . . . Aluminum Ribbon

Magnetic Material . . . . . . . . . . . . . . Neodymium radial

Stray Flux Shielding . . . . . . . . . . . . . Inherent

Magnetic Gap Depth (He) . . . . . . . . 50.8 mm

Cone Material . . . . . . . . . . . . . . . . . Aluminum

Surround Material . . . . . . . . . . . . . . Injecton molded rubber

Polarity, Outward Motion . . . . . . . . . Positive voltage on (+) terminal

Net Weight . . . . . . . . . . . . . . . . . . . . 20.1 kg

Thiele / Small Parameters

Resonant Frequency (Fo) - Fs . . . . . 20 Hertz

Voice Coil DC Resistance - Re . . . . . 3.3 ohms

Total Q - Qts . . . . . . . . . . . . . . . . . . 0.37

Mechanical Q - Qms . . . . . . . . . . . . 8.0

Electrical Q - Qes . . . . . . . . . . . . . . 0.40

Equivalent Volume of Air - Vas . . . . . 169 L

Radiating Piston Area - Sd . . . . . . . . 765 cm 2

Electrical / Mechanical Parameters

Flux Density x Length - BL . . . . . . . . 18 Tesla-meters

Compliance - Cms . . . . . . . . . . . . . . 206 mm/N

Total Mass - Mms . . . . . . . . . . . . . . 314 grams

Impedance

Frequency Response (1W, 1m)

Maximum Excursion . . . . . . . . . . . . . 75 mm peak to peak

Xmax . . . . . . . . . . . . . . . . . . . . . . . . 38 mm peak to peak

Distortion (1W, 1m)

I purchased one last night, read a ton of reviews and have yet to find anything negative about them, these ar used in Wilson Audio cabs

Those will work very well in IB. Xmax is also a concern. You will want a lot of linear travel to get useable output.//content.invisioncic.com/y282845/emoticons/verymad.gif.3f39c5c2fd57527b671fad3efdfac756.gif

5 Or better is a rule of thumb but way off from necessity when doing IB. When placed in the vehicle the final system Q will raise dramatically.