DiyMobileAudio.com Car Stereo Forum banner
1 - 20 of 39 Posts

·
Registered
Joined
·
29 Posts
Discussion Starter · #1 ·
Hello Friends. I am looking for whole internet to find out specs about the 33wx2 subwoofer box specs. The only one is from focal and it is mentioning vented box.
I want to know all specs for all kind of box types. Why focal is not providing these datas with customers same like JL or audison for example?
I know the vented specs but i want to know Sealed specs and inverse mounting?
 

·
Registered
Joined
·
1,469 Posts
Because the EBP for the 33WX2 means it will not work well in a sealed enclosure:
Product Rectangle Font Screenshot Parallel
 

·
Registered
Joined
·
29 Posts
Discussion Starter · #3 ·
I have never seen 33wx2 in vebted box. In turkey everybody installs in sealed box something like 40 50 liters... the installators says recommends sealed box for punchier bass and more controlled.

This is making me confused. Can you send me a link from the sbd value page pls so i can have a look into other specs too...
 

·
Registered
Joined
·
1,469 Posts
The 33WX(2) is made to old PA Sub standards... low xmax and High Efficiency - it really wants a big ported box. If you put them in bigger than 25L sealed then you reduce power handling substantially without HP Filters to filter out the bass below 30Hz. You can run them sealed but if you're going to run 350W RMS (or more) to it then don't go any bigger than 25L. If you really want to maximize the low frequency and get better SQ out of them then go to 50-100L and ported.

You lose 10dB of output by putting them in sealed boxes and that's equivalent to having 3 of them versus only one. It's not that it can't be run Sealed it is simply a waste of their potential to do so; unless you have to due to space.

Here's the analysis:

This is with cabin gain modeled from 15-80Hz for a standard 4D Sedan.

White Trace is 25L Sealed - hit's mechanical limits at 350W at 20Hz
118dB at 30-31Hz

Pink Trace is 50L Sealed - hit's mechanical limits at 200W at 30Hz
Reduced power, reduced bandwidth, possible mechanical damage without HP at 30Hz

Green Trace is 45L Ported at 36Hz - pushes mechanical limits to 700W
This would not be good for thermal power handling so we make the box bigger to align with Focal RMS ratings.

Blue Trace is 100L Ported at 30Hz - hit's mechanical limits at 350W
128.3dB at 31-32Hz with a nice gradual rolloff to blend with midbasses.
Rectangle Product Slope Font Computer
 

·
Registered
Joined
·
29 Posts
Discussion Starter · #5 ·
The 33WX(2) is made to old PA Sub standards... low xmax and High Efficiency - it really wants a big ported box. If you put them in bigger than 25L sealed then you reduce power handling substantially without HP Filters to filter out the bass below 30Hz. You can run them sealed but if you're going to run 350W RMS (or more) to it then don't go any bigger than 25L. If you really want to maximize the low frequency and get better SQ out of them then go to 50-100L and ported.

You lose 10dB of output by putting them in sealed boxes and that's equivalent to having 3 of them versus only one. It's not that it can't be run Sealed it is simply a waste of their potential to do so; unless you have to due to space.

Here's the analysis:

This is with cabin gain modeled from 15-80Hz for a standard 4D Sedan.

White Trace is 25L Sealed - hit's mechanical limits at 350W at 20Hz
118dB at 30-31Hz

Pink Trace is 50L Sealed - hit's mechanical limits at 200W at 30Hz
Reduced power, reduced bandwidth, possible mechanical damage without HP at 30Hz

Green Trace is 45L Ported at 36Hz - pushes mechanical limits to 700W
This would not be good for thermal power handling so we make the box bigger to align with Focal RMS ratings.

Blue Trace is 100L Ported at 30Hz - hit's mechanical limits at 350W
128.3dB at 31-32Hz with a nice gradual rolloff to blend with midbasses.
View attachment 311159
if you check the web i just saw them in sealed boxes never vented (ported) ported and vented means same i guess.
In focal pdf i see 45 vented recommended and you wrote above not good for thermal power.

What i exactly want from sub is not sq i want SQL it should be powerful LOUD but controlled clean bass. I am thinking also to go to JL 13 inch one but they want much more space in bmw f30 there is no such space. I cut all the car for music system but i am not happy still. anyway long story short: Can you suggest me max loudness and cleanest and punchiest bass. I dont like looooong bass i like shourt and cut and controlled one it should be fast not slow. I dont know if i could express my self.

Thank you very much for your time...
 

·
Registered
Joined
·
1,469 Posts
Maximum that it can do safely is 350 Watts per the manufacturer so if we tune a ported box to maximize output at that wattage level we get 200 Liters at 38 Hz - you'll never get SQL sealed from a Subwoofer with 9mm of xmax. It's gonna be peaky and not have much output on either side of the tuning point but that's what it can do in the right enclosure.
Colorfulness Rectangle Slope Line Font


Somewhere between this and the blue line in the previous which is the maximum SQL it can do ported.
 

·
Registered
Joined
·
1,469 Posts
last diagram is peaking something like ONLY 39hz. is there any linear one? that i can hear all frequencies at max level.? (as max as possible?
That's the green line from the original model. 45 L at 36 Hz - that nice smooth curve is what it looks like once it's in the car and cabin gain is added.
 

·
Registered
Joined
·
29 Posts
Discussion Starter · #9 ·
That's the green line from the original model. 45 L at 36 Hz - that nice smooth curve is what it looks like once it's in the car and cabin gain is added.
yes but again you mentioned not good for thermal? i dont want to take risk anymore. I spent in total 40k euro to auido system and this time should end with perfect result please
 

·
Registered
Joined
·
29 Posts
Discussion Starter · #11 ·
omg this is so complicated... vent size is also important.... diameter and depth and the volume of the box are all related to each other. I want just one rule for me to proceed. Howmany liter box vented or sealed for max rms power and linear sound vent details for me. Then i will proceed please help me :(
 

·
Registered
Joined
·
1,469 Posts
And this 45 liters is net liters except the subwoofer. How can i know what is the subwoofer volume? Is there any spec for this?
Focal does not specify the displacement and this has been discussed before:

The Focal recommendations take into account driver displacement and give vent dimensions.
45L is gross from Focal then drop the Sub in and cut the port.
36 Hz = 100mm diameter x 330mm long port
40 Hz = 100mm diameter x 250mm long port

Start Long and work down till you get the sound 'You' want...
 

·
Registered
Joined
·
1,469 Posts
Quit cross posting and double posting or the Mods will lock your post.
 

·
Registered
Joined
·
29 Posts
Discussion Starter · #14 ·
to have lowest bass 36 hz i must use 33cm long port but i can have maximum 25cm depth. I cut the car base in the trunk and made there 85 to 90 liters for both sub. depth is maximum 25cm. is there any other way to get 36hz with different size port? something like 8cm or 12cm to25cm depth?

minimum how many cm i must have after the port? port can not touch to back side isnt it otherwise it will have no function
 

·
Registered
Joined
·
1,469 Posts
to have lowest bass 36 hz i must use 33cm long port but i can have maximum 25cm depth. I cut the car base in the trunk and made there 85 to 90 liters for both sub. depth is maximum 25cm. is there any other way to get 36hz with different size port? something like 8cm or 12cm to25cm depth?

minimum how many cm i must have after the port? port can not touch to back side isnt it otherwise it will have no function
Can you put an elbow on it and extend that way?
 

·
Registered
Joined
·
1,469 Posts
9 cm port puts you right at 25 cm and on the verge of port compression along with port noise.

10 cm x 33 cm port is the minimum I would recommend to avoid port noise - you can put an elbow on it and extend vertically or horizontally to get the total length - measure through an elbow by measuring the center line with the curve and like mentioned previously start long and cut down to length based on listening tests.
 

·
Registered
Joined
·
1,469 Posts
yes i can sure. will this effect the quality? or strength? what is the specs than? if i have 23 cm depth? L shape in total 25cm (13cm + 12cm) will work same like I shape 25cm?
Won't hurt integrity at all - extend to the back and secure to the back wall if you can... imagine the initial section being about 20cm +/- and then extend along the back wall the final 15cm or so and then if it's too deep cut that down 1cm at a time till you get the sound you want.
 
1 - 20 of 39 Posts
Top