Terrible oversized bandpass enclosure for 2 kicker compc 12”

[Wayne Clark]

it’s my first subwoofer enclosure so idc that it’s ugly as shit and is way oversized, the goal here was to get as deep as possible with a gradual falloff to account for audibility loss as frequencies decrease. The result being of course it won’t be super loud but I don’t need it to be. Anyways just wanted to share it. Single reflex bandpass enclosure isobaric push pull, 4ft^3 sealed end 3ft^3 vented chamber + 15inx4inx50in vent

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[shredder1 10+ year member]

it’s my first subwoofer enclosure so idc that it’s ugly as shit and is way oversized, the goal here was to get as deep as possible with a gradual falloff to account for audibility loss as frequencies decrease. The result being of course it won’t be super loud but I don’t need it to be. Anyways just wanted to share it. Single reflex bandpass enclosure isobaric push pull, 4ft^3 sealed end 3ft^3 vented chamber + 15inx4inx50in vent

If you're asking for advice I'd size the sealed side mid-hi 40's and port the vented side tuned the same with an under 75fps port velocity.
Understand that in some cases 4ths wont be the way to go if its a hi-EBP sub. A Kicker should serve tho.

 

[Wayne Clark]

If you're asking for advice I'd size the sealed side mid-hi 40's and port the vented side tuned the same with an under 75fps port velocity.
Understand that in some cases 4ths wont be the way to go if its a hi-EBP sub. A Kicker should serve tho.

Too late the sealed side is 113 vented side is 80L chamber attached to vent tuned to 30hz and 10m/s which is like 35fps I think

 

[shredder1 10+ year member]

Too late the sealed side is 113 vented side is 80L chamber attached to vent tuned to 30hz and 10m/s which is like 35fps I think

You tuned a 4th to 30hz?

 

[Wayne Clark]

You tuned a 4th to 30hz?

It’s ridiculously oversized but yes

 

[shredder1 10+ year member]

Oh boy... fine its your gear and your ears but...

No comment except are you looking for a low power HT tuning in a moving vehicle or something?

 

[Wayne Clark]

Oh boy... fine its your gear and your ears but...

No comment except are you looking for a low power HT tuning in a moving vehicle or something?

That’s exactly what I was going for I wasn’t really sure how to get the fall off for bass as it gets higher other than using a big *** isobaric bandpass like this hoe or wiring a butterworth low pass

 

[shredder1 10+ year member]

That’s exactly what I was going for I wasn’t really sure how to get the fall off for bass as it gets higher other than using a big *** isobaric bandpass like this hoe or wiring a butterworth low pass

Why don't you tune around 45fs sealed and size the front port 75fps tuned the same. I guarantee delay will be under 25ms and impedances will work out with a smooth response digging low. No hate but NEVER tune a 4th 30hz bro... your goals could be better attained thru experience. Ask someone next time.
A 53" long port is a BIG red flag. I almost didn't throw in my .02 but... I'm here to help.

 

[1aespinoza Premium Member]

Why don't you tune around 45fs sealed and size the front port 75fps tuned the same. I guarantee delay will be under 25ms and impedances will work out with a smooth response digging low. No hate but NEVER tune a 4th 30hz bro... your goals could be better attained thru experience. Ask someone next time.
A 53" long port is a BIG red flag. I almost didn't throw in my .02 but... I'm here to help.

Dang it! This is all Chinese to me but it sounds awesome.

 

[shredder1 10+ year member]

Why don't you tune around 45fs sealed and size the front port 75fps tuned the same. I guarantee delay will be under 25ms and impedances will work out with a smooth response digging low. No hate but NEVER tune a 4th 30hz bro... your goals could be better attained thru experience. Ask someone next time.
A 53" long port is a BIG red flag. I almost didn't throw in my .02 but... I'm here to help.

If you are looking for low end extension I'd opt for a +- 1.5:1 ratio and understand any resonance below the drivers Fs with a EBP over 60 will affect power handling. I like 1.5-2.25:1 on most 4ths depending on driver characteristics once the sealed side is determined. Always watch delay (-25ms) for an accurate result.
Your peak is not what Winisd says, Experience and a designers knowledge can make the response you see FAR more accurate once cabin gain is applied to your modeling depending on your vehicle. Coupes and trunks generally gain around 50-60hz, Suv's with more cabin space gain anywhere from 45hz-35hz so anything you design could have a half (almost) octave lower gain to match. I use resonance and ratio to smooth final response out if everything else looks good. Consider this... all frequencies reproduced with authority is far preferable to making something that underperforms within a narrow bandwidth. In my exp a well designed 4th for 2-12s will at least reproduce -25-70hz if ratioed correctly.
I'd focus on making a 1.5:1 4th sized for 45hz sealed and enough port to keep velocities under 75fps myself. Everything else should fall in line once built. A 30hz 4th? comon' bro...

 

[Wayne Clark]

If you are looking for low end extension I'd opt for a +- 1.5:1 ratio and understand any resonance below the drivers Fs with a EBP over 60 will affect power handling. I like 1.5-2.25:1 on most 4ths depending on driver characteristics once the sealed side is determined. Always watch delay (-25ms) for an accurate result.
Your peak is not what Winisd says, Experience and a designers knowledge can make the response you see FAR more accurate once cabin gain is applied to your modeling depending on your vehicle. Coupes and trunks generally gain around 50-60hz, Suv's with more cabin space gain anywhere from 45hz-35hz so anything you design could have a half (almost) octave lower gain to match. I use resonance and ratio to smooth final response out if everything else looks good. Consider this... all frequencies reproduced with authority is far preferable to making something that underperforms within a narrow bandwidth. In my exp a well designed 4th for 2-12s will at least reproduce -25-70hz if ratioed correctly.
I'd focus on making a 1.5:1 4th sized for 45hz sealed and enough port to keep velocities under 75fps myself. Everything else should fall in line once built. A 30hz 4th? comon' bro...

Not for me, my personal thing was to make the low frequencies as loud as I possibly coul, but yeah the cabin gain in mine is probably hovering around 40hz that’s why I wanted a cutoff before them. I’m doing my best to isolate the lower frequencies so that the bass isn’t super loud at 35hz then drops down after that, it ruins the music for me

 

[shredder1 10+ year member]

Not for me, my personal thing was to make the low frequencies as loud as I possibly coul, but yeah the cabin gain in mine is probably hovering around 40hz that’s why I wanted a cutoff before them. I’m doing my best to isolate the lower frequencies so that the bass isn’t super loud at 35hz then drops down after that, it ruins the music for me

Ok.

 

[spokey9 5,000+ posts]

make the low frequencies as loud as I possibly coul,

Ever think about going ib?

 

[Wayne Clark]

Ever think about going ib?

Idk what that is fill me in tho

 

[spokey9 5,000+ posts]

Idk what that is fill me in tho

Infinite baffle. You'll get a lower roll off point at the upper end think 50-60hz but the low end will be more pronounced



If you sealed off the rear wave from the from wave coming off the sub in a large enough area...bam ib