sub build need expert help...WmAx, you there?

Whitey80

Whitey80

Senior Audioholic
Have 2 12" Infinity Kappa 120.1SE's (older green cone, NOT Perfects. These are svc 4ohm 300w rms)
Wanting to build 2 seperate ported enclosures for these.

I have read through all of the other build threads for the 12.1's but these need different volumes, I'm sure.
Also, very budget consious and not familiar with all of the setup of the Behringer controller and such. I can do a pair of Bash 300w plate amps within my budget knowing I will lose alot of control.

1st question....with this combo...will it be worth it?
2nd question...what should my enclosure be? (thiele small below)

Thiele-Small Parameters--
VOICE COIL DC RESISTANCE: REVC (OHMS) . . . . . . 3.32
VOICE COIL INDUCTANCE @ 1 KHZ: LEVC (MH). . . . . . . . 3.65
DRIVER RADIATING AREA: SD (IN2) . . . . . . . . 78.86
SD (CM2). . . . . . . 511.00
MOTOR FORCE FACTOR: BL (TM) . . . . . . . . 12.66
COMPLIANCE VOLUME: VAS (FT3). . . . . . . . . 6.21
VAS (LITERS). . . . . 146.47
SUSPENSION COMPLIANCE: CMS (μM/N) . . . . 395.00
MOVING MASS, AIR LOAD: MMS (GRAMS) . . . . 126.45
MOVING MASS, DIAPHRAGM: MMD (GRAMS). . . . 119.80
FREE-AIR RESONANCE: FS (HZ) . . . . . . . . 22.52
MECHANICAL Q: QMS . . . . . . . . . . . 12.44
ELECTRICAL Q: QES . . . . . . . . . . . . 0.37
TOTAL Q: QTS . . . . . . . . . . . . 0.36
MAGNETIC-GAP HEIGHT: HAG (IN) . . . . . . . . . 0.31
HAG (MM) . . . . . . . . 8.00
VOICE-COIL HEIGHT: HVC (IN) . . . . . . . . . 1.20
HVC (MM) . . . . . . . 30.48
MAXIMUM EXCURSION: XMAX (IN) . . . . . . . . 0.44
XMAX (MM). . . . . . . 11.24
 
TLS Guy

TLS Guy

Seriously, I have no life.
Have 2 12" Infinity Kappa 120.1SE's (older green cone, NOT Perfects. These are svc 4ohm 300w rms)
Wanting to build 2 seperate ported enclosures for these.

I have read through all of the other build threads for the 12.1's but these need different volumes, I'm sure.
Also, very budget consious and not familiar with all of the setup of the Behringer controller and such. I can do a pair of Bash 300w plate amps within my budget knowing I will lose alot of control.

1st question....with this combo...will it be worth it?
2nd question...what should my enclosure be? (thiele small below)

Thiele-Small Parameters--
VOICE COIL DC RESISTANCE: REVC (OHMS) . . . . . . 3.32
VOICE COIL INDUCTANCE @ 1 KHZ: LEVC (MH). . . . . . . . 3.65
DRIVER RADIATING AREA: SD (IN2) . . . . . . . . 78.86
SD (CM2). . . . . . . 511.00
MOTOR FORCE FACTOR: BL (TM) . . . . . . . . 12.66
COMPLIANCE VOLUME: VAS (FT3). . . . . . . . . 6.21
VAS (LITERS). . . . . 146.47
SUSPENSION COMPLIANCE: CMS (μM/N) . . . . 395.00
MOVING MASS, AIR LOAD: MMS (GRAMS) . . . . 126.45
MOVING MASS, DIAPHRAGM: MMD (GRAMS). . . . 119.80
FREE-AIR RESONANCE: FS (HZ) . . . . . . . . 22.52
MECHANICAL Q: QMS . . . . . . . . . . . 12.44
ELECTRICAL Q: QES . . . . . . . . . . . . 0.37
TOTAL Q: QTS . . . . . . . . . . . . 0.36
MAGNETIC-GAP HEIGHT: HAG (IN) . . . . . . . . . 0.31
HAG (MM) . . . . . . . . 8.00
VOICE-COIL HEIGHT: HVC (IN) . . . . . . . . . 1.20
HVC (MM) . . . . . . . 30.48
MAXIMUM EXCURSION: XMAX (IN) . . . . . . . . 0.44
XMAX (MM). . . . . . . 11.24
Sorry, but I have to break the bad news to you. Those drivers are not suitable for home HT, car use only.

They are intended for a sealed enclosure. This is the best vented model.

Name: Kappa 120.1se
Type: Standard one-way driver
Company: Infinity Systems Inc.
Comment: Kappa series
No. of Drivers = 1
Fs = 22.52 Hz
Qms = 12.44
Vas = 146.5 liters
Cms = 0.395 mm/N
Mms = 119.8 g
Rms = 1.438 kg/s
Xmax = 11.24 mm
Xmech = 16.86 mm
P-Dia = 255.1 mm
Sd = 511 sq.cm
P-Vd = 0.574 liters
Qes = 0.37
Re = 3.32 ohms
Le = 3.65 mH
Z = 4 ohms
BL = 12.66 Tm
Pe = 300 watts
Qts = 0.36
no = 0.436 %
1-W SPL = 88.54 dB
2.83-V SPL = 94 dB
-----------------------------------------
Box Properties
Name:
Type: Vented Box
Shape: Prism, square (optimum)
Vb = 2.881 cu.ft
Fb = 23.51 Hz
QL = 6.594
F3 = 33.51 Hz
Fill = minimal
No. of Vents = 1
Vent shape = rectangle
Vent ends = two flush
Hv = 3 in
Wv = 7 in
Lv = 32.08 in

Fs is really too high for home HT and there is a huge ripple peak of 9 db between 90 and 100 Hz. Enlarging the enclosure makes no significant difference to Fs but makes the ripple a lot worse.

You can not Eq a ported box, because the driver decouples.

Now sealed is not ideal for home HT either.

Name: Kappa 120.1se
Type: Standard one-way driver
Company: Infinity Systems Inc.
Comment: Kappa series
No. of Drivers = 1
Fs = 22.52 Hz
Qms = 12.44
Vas = 146.5 liters
Cms = 0.395 mm/N
Mms = 119.8 g
Rms = 1.438 kg/s
Xmax = 11.24 mm
Xmech = 16.86 mm
P-Dia = 255.1 mm
Sd = 511 sq.cm
P-Vd = 0.574 liters
Qes = 0.37
Re = 3.32 ohms
Le = 3.65 mH
Z = 4 ohms
BL = 12.66 Tm
Pe = 300 watts
Qts = 0.36
no = 0.436 %
1-W SPL = 88.54 dB
2.83-V SPL = 94 dB
-----------------------------------------
Box Properties
Name:
Type: Closed Box
Shape: Prism, square (optimum)
Vb = 2.881 cu.ft
Qtc = 0.474
QL = 6.594
F3 = 53.8 Hz
Fill = heavy

Second order roll of fstarts around 70 Hz with an F3 of around 54 Hz. There is more low bass with this driver sealed than vented. You can Eq a sealed box, but xmax is used up by 30 Hz without Eq.

If you want to use this driver for home HT, then your best bet is the sealed enclosure. You would need to add Eq at 12 db per octave starting around 70 Hz. However because of the Eq required, output would be limited. So you could get good quality bass, but you would have to play it softly. You won't get room shaking bass from these drivers.

If you put both drivers in a box around 6 cu.ft then you would gain 6 db output, and be better, but for the size of box required, in my view not worth it. But you have the drivers and the two to a box, or two 2.88 boxes close together would up your output, but still not be thunderous.
 
Whitey80

Whitey80

Senior Audioholic
Thanks for all the info, it's very helpful.
I had a pair of the Perfect 12.1's and gave them away after I lost all interest in car audio a while back....oops.
These 2 have been laying around forever and thought I may be able to put them to use now that I have started developing more interest in HT.
I'll just pass these ones on and start from scratch with another set 12.1's
 
WmAx

WmAx

Audioholic Samurai
These drivers are also not the 'grade' of the Perfects. Not worth the effort of building cabs. However, the new Kappas that just came out are the new premium subs for SQ from Infinity(Kappa 120.9W) are apparently a pure SQ driver to take place of the Kappa Perfects. But right now, you can get Audiopulse Epic drivers on a great deal from partsexpress.com since they are on clearance.

-Chris
 
T

TheChineseDude

Audiophyte
i just purchased a single Kappa 120.9w from Crutchfield. I put it into a ported box in my trunk, and, and let me tell you: this thing is no joke ! You really gotta hear it to believe it.
 
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