6 replies to this topic

[Inspiron]

Hi guys

I've recently found the Theile/small parameters for a Kenwood KFC 1004DB. They are as follows:

FS = 24.40hz
Vas = 79L
QMS = 6.446
QES = 0.462
QTS=0.431
Z = 4 ohm
Re = 3
Le = 0.9
Diaphragm diameter= 25.4cm (10 inch sub)
Xmax = 12mm
Sensitivity = 92dB/W
Driver radiating area = 350cm^2

I've plugged in the values into BassBox 6 pro. This program has recommended a sealed box. I've also completed a ported box design, as the ported design produced by BassBox 6 pro was too large. Ideally I'd like to keep the box under The 2 box properties are shown below:

Sealed box:

Box Properties
Type: Closed Box
Shape: Prism, square (optimum)
Vb =  17.86 liters
Fb =  52.82 Hz
QL =  7
F3 =  48.75 Hz
Qtc =  0.87
Fill = none

Ported box:

Type: Vented Box
Shape: Prism, square (optimum)
Vb =  35 liters
Fb =  32.14 Hz
QL =  6.6
F3 =  33.66 Hz
Fill = none
No. of Vents = 2
Vent shape = round
Vent ends = one flush
Dv =  50 mm
Lv =  300 mm

I've attached the amplitude response curves for box boxes (refer to attachment).

I'm wondering if F3 being higher than Fb is a bad thing??

If it helps, I listen to a fairly wide range of music, from rock, metal, the 60's/70's classics you hear on radio to dance. It all depends on what I'm doing and what the time is...

If the boxes are not ideal, could somebody recommend me another size?

Cheers

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[Inspiron]

Anybody???

[268669♫]

I'd go sealed but closer to 25-28L.

Ant

[Inspiron]

I'd go sealed but closer to 25-28L.

Ant

Ok, but why? Is this due to your musical tastes, or the small parameters I previously posted???

Edited by Inspiron, 01 November 2011 - 09:33 AM.

[lunchietey]

Both boxes would be ok, but a slightly larger sealed would not be as boomy, a q of .87 is a little high but would do ok. The ported box would he good for more spl, and a bit of extra around 50hz which will add weight to top 40 type music. Do you want it as loud as you can or do you want the best quality? Oh and the other thing is you can't seee what cone excursion will be without plotting it. The sealed box will always be the safest. Any prefab sealed box would prob be fine if you're not trying to fit a given space

Edited by lunchietey, 01 November 2011 - 11:41 AM.

[Inspiron]

Both boxes would be ok, but a slightly larger sealed would not be as boomy, a q of .87 is a little high but would do ok. The ported box would he good for more spl, and a bit of extra around 50hz which will add weight to top 40 type music. Do you want it as loud as you can or do you want the best quality? Oh and the other thing is you can't seee what cone excursion will be without plotting it. The sealed box will always be the safest.

Thanks for your response.

I'd ideally like both SQ and SPL, but leaning slightly closer to SQ. Hence why I went with a port frequency closer to 30Hz.

I've also plotted cone excursion (refer below). Max cone excursion is 12mm. From the graph, this will occur around 23Hz. Does this really pose a problem if the frequency response of the sub is 25-600Hz???

Also, is the F3 being higher in frequency than Fb point a bad thing? Is this related to cone excursion?

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[Inspiron]

Anybody???