Is this bandpass wrong?

[fika93]

Hello guys, i've got this old sub.Its strange that front part of subwoofer is closed and the back one have hole.I've put some images so u can see how that actually look like.I am confused, i googled for a while, i've never found something like this.Is this wrong?

 

[Crashpc]

Yes, this is completely possible to do. It´s one kind of the bandpass box. Yet it will most likely be wrongly tuned and inefficient. I would rebuild it...

 

[Smitske96]

4th order bandpass 😉

 

[LORDSANSUI]

probably who made it prefer to use rear vented in order to improve heat trasnfer and reduce power compression in some way.

You could do reverse engineering to simulate what you have in hands

 

[fika93]

Thank you guys!🙂

 

[fika93]

Anyway, is this bandpass fine or i can make it better?

 

[TBTL]

Could you provide some more data? Box chamber volumes, port dimensions, Thiele-Small parameters of the woofer.

 

[BP1Fanatic]

probably who made it prefer to use rear vented in order to improve heat transfer and reduce power compression in some way.

Exactly! I always build my BP4's this way. How do you expect a vented voice coil to get cool air in a closed box???

 

[David Morison]

Exactly! I always build my BP4's this way. How do you expect a vented voice coil to get cool air in a closed box???

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

Hi,
I think you need to change the settings you're using in your google account to make these photos publicly viewable - even after logging in to google all I'm getting is an unavailable notification.
Thanks,
David.

 

[BP1Fanatic]

I have these settings in Google Photos.

Sharing
Manage preferences for sharing

Sharing suggestion notifications
Receive notifications when you have new photos to share with friends
OFF

Remove video from motion photos
Share only the still photos when sharing by link & in albums
OFF

Remove geo location in items shared by link
Affects items shared by link but not by other means
ON

 

[Brian Steele]

...and we're still not seeing them...

The one surefire way to ensure that photos are visible here is to actually upload them here is part of your post, rather than embedding images that are located on another site.

 

[BP1Fanatic]

I wasn't on my phone when I posted those pictures. My work laptop does not have those pictures to upload, hence using the link function to Google Photos. I'm on my phone now. Here are those same pictures.