'99 Civic Sedan - sound system build up

[wixxer]

clean up your message box mate

[curtis265]

cleeeaaaaned bro

[UkuleleGod]

Guys, thanks for comments!
These two days I didn't do much on the box itself, but I played with WinISD for quite some time. Unfortunately, I'm not really sure how does a good curve look like, or what's the real world behaviour of the sub when the curve says that it will be overall louther then "another" box/port combo, but it has a big peak at, say, 45Hz. (+6dB), compared with -3dB at 30Hz an 89Hz.
@ UkuleleGod: mate, is it too much to ask you to run my sub through WinISD and see what you can come up with? Would appreciate it much. Or someone else please?
Thanks

The curve you are looking for all depends on whether you want a SPL or a SQL system. But the best way to figure out what your sub needs is to check out the specs from the manufacturer (which I would also need to check out a winISD). Easiest way out would be just to try and get as close to what the manufacturer wants. You also should remember, that some frequencies will also be reinforced by the interior environment the sub is in.

You could possibly decrease the volume of the enclosure by using a closed cell foam (this type of foam decreases volume, where as "open cell foam" has the potential to increase volume).

Hope that Helps, it is a clean looking setup you are going for, kinda guilts me into making a custom enclosure for my sub instead of just using the tuned MTX one :P

[TheSaint]

so much dead weight - that poor civics power to weight ratio just went out the window - not to mention the extra weight over the back wheels
i would be uprating the swaybar, tie brace and trailing arm bushes lol

otherwise - some nice DiY work there - respect for the hard yards

[wixxer]

The curve you are looking for all depends on whether you want a SPL or a SQL system. But the best way to figure out what your sub needs is to check out the specs from the manufacturer (which I would also need to check out a winISD). Easiest way out would be just to try and get as close to what the manufacturer wants. You also should remember, that some frequencies will also be reinforced by the interior environment the sub is in.

You could possibly decrease the volume of the enclosure by using a closed cell foam (this type of foam decreases volume, where as "open cell foam" has the potential to increase volume).

Hope that Helps, it is a clean looking setup you are going for, kinda guilts me into making a custom enclosure for my sub instead of just using the tuned MTX one :P

Thanks for your tips mate, much appreciated. I thought the best thing would be to pass you the specs, and if you're happy to check it out in WinISD that would be great!!!
I was thinking (also after playing with WinISD that the 3'' port might get too noisy, so will opt for 4''. 5'' would be awesome, but I'm not sure if I can easy find a 5'' pipe, and secondly If I can bend it to fit in the enclosure. Bigger pipe would also take up much more space inside the enclosure, giving me "less work" to decrease the remaining volume .
Question: Does it matter if the port has quite a few bends (to suit the enclosure), as long as I can keep the diameter constant and it's all smooth inside? Is it too bad if I can't keep 1x port diameter distance from enclosure walls?
Here are the specs:
Rainbow Hammer 12''
Peak power handling 750 Watt
Nominal power handling 400 Watt
Frequency response 25-200 Hz
DC-Resistance 2 x 2 Ohm
Max. SPL in car (ported) 146 dB @ 35-120 Hz
Magnet weight 3650 Gramm
Frame diameter 316mm
Mounting diameter 286mm
Basket rim height wo / w. ring 10 / 18 mm
Mounting depth 146 mm
Overall depth 166mm
Magnet diameter 180mm
Displacemet 4.0 l
Suitable for… enclosure
Fs 32 Hz
Redc* 4.1 Ohm
Qms 4.12
Qes 0.4
Qts 0.37
Le* 3.21 mH
Vas (Sd) 50 Litres
Sd 502 cm²
Z @100 Hz* 5.7 Ohm
Z @1 kHz* 28.4 Ohm
Z @10 kHz* 109 Ohm
Rms 7.4 kg/s
Xmax 23 mm
Recommended subsonic cutoff frequency 20-35 Hz /18-24 dB/octave
Important: all specs are measured with voice coils in series.

Enclosure:
Sealed minimum : 20 Liter
Ported minimum : 32 Liter, Aeroport-tube Ø / length : 17cm

Recommended enclosures (including displacement of subwoofer):
Ported 1
Volume 35 lt
Port 1x Aeroport 3'', length 17 cm
Tuning frequency 35 Hz / F3=37 Hz

Ported 2
Volume 45 lt
Port 1x Aeroport 3'', length 15 cm
Tuning frequency 33 Hz / F3=34 Hz
----------------------------------
If you get the chance, please check it out for me. Please take into account my current total volume (69 litres), see if you can do some magic
I'll shoot you a PM with my email address, maybe you could forward a WinISD file you generate.
And I'm going for a SQL, not for SPL.

Thanks

[wixxer]

so much dead weight - that poor civics power to weight ratio just went out the window - not to mention the extra weight over the back wheels
i would be uprating the swaybar, tie brace and trailing arm bushes lol

otherwise - some nice DiY work there - respect for the hard yards

hehe, dead in means of sound deadening stuff... is not really much inside...yet. And it can never be too much
btw, since my son is a newbie driver, the slower he drives, the better I can sleep
Thanks for your approval on my DIY work mate, appreciate it

-----------------

Anyway, last night did a bit more sanding, gotta go to Supacheap and get some fine filler, there are quite some low points there...

[TheSaint]

dead weight as in - it slows the car down haha
but in the case of slowing down your son i think its a fantastic idea haha

the power of DiY is epic win

[UkuleleGod]

Just ran your sub through ISD and got pretty similar to what you got. Your enclosure is (as you said) about 17 liters bigger than it really needs to be, too much bigger and you will end up with a higher SPL. You could even out the size, by filling the enclosure (temporarily with something like plastic bags full of sand or with some closed cell foam) and see how it sounds? If it sounds boomy, possibly lengthening the port could help. The longer port will lower the resonant frequency.

I don't think there should be that much of effect if the port is bent, as long as the diameter is constant and smooth. I have seen enclosures where the port has been as close as 1/2 the diameter from the enclosure walls so that should be fine too.

Hope that Helps!

[wixxer]

Just ran your sub through ISD and got pretty similar to what you got. Your enclosure is (as you said) about 17 liters bigger than it really needs to be, too much bigger and you will end up with a higher SPL. You could even out the size, by filling the enclosure (temporarily with something like plastic bags full of sand or with some closed cell foam) and see how it sounds? If it sounds boomy, possibly lengthening the port could help. The longer port will lower the resonant frequency.

I don't think there should be that much of effect if the port is bent, as long as the diameter is constant and smooth. I have seen enclosures where the port has been as close as 1/2 the diameter from the enclosure walls so that should be fine too.

Hope that Helps!

It helps heaps! Thank you so much mate

...but in the case of slowing down your son i think its a fantastic idea haha...

well said mate, haha

[wixxer]

@UkuleleGod:
Just one more quick question, then I'm off to do moooooore sanding (will it ever end...?):
Am I correct to measure the port length through the "centre" of the pipe, as the blue line shows in the graphic below?



Question is because somewhere I read that one should measure "the shortest way of air" which would not be the centre, but rather "from one corner to the opposite, and so on to the next one". It doesn't sound logical to me, I reckon my way is correct.

[UkuleleGod]

@UkuleleGod:
Just one more quick question, then I'm off to do moooooore sanding (will it ever end...?):
Am I correct to measure the port length through the "centre" of the pipe, as the blue line shows in the graphic below?



Question is because somewhere I read that one should measure "the shortest way of air" which would not be the centre, but rather "from one corner to the opposite, and so on to the next one". It doesn't sound logical to me, I reckon my way is correct.

One this one, I am not too sure. I would imagine just down through the centre, either way, there will only be a few centimeters difference.

Hope this all turns out well.

Can't wait to see the finished product!

[wixxer]

One this one, I am not too sure. I would imagine just down through the centre, either way, there will only be a few centimeters difference.

Hope this all turns out well.

Can't wait to see the finished product!

Same here!!!