Is this sub built to be ported or sealed??

[audio_phill 10+ year member]

lol, if that be the case then the specs be way wrong, lol. The High Qts is gonna make the "boominess" worse and worse the higher you tune.

 

[CoilBurner]

What about this?? What kinda box is this??

YouTube - 8 Hifonics 12"s

Ive got 37.5" width and 30" height...

 

[audio_phill 10+ year member]

lol, those vid's dont show alot of anything too impressive, if those were the S4 Version they would outperform the D4's quite easily if the specs are on.

This s more mpressive to me, lol

Standard Ultra 8's in a Car video by AudioPhill - Photobucket

 

[audio_phill 10+ year member]

What about this?? What kinda box is this??
YouTube - 8 Hifonics 12"s

Ive got 37.5" width and 30" height...

Thats just a sloppy designed 4th order, I potted them up for 4th order, to get any real usable freq response out of them is virtually impossible in a 4th order given the D4's specs. If your destin to run a entry level multi-sub system for few bucks, check out the quantum subs. If those specs are true, no matter how nice they seem to sound in the vids, they will sound like crap in person. Im no inexperienced idiot, I go through prob 100 subs a year lately and have hands on pulled TSP's from over 700 woofers in the last 17 years, TSP's tell you everything ya need to know when properly plotted, the graphs I posted wont lie if the TSP's are correct on the site.

 

[audioholic 5,000+ posts]

What about this?? What kinda box is this??
YouTube - 8 Hifonics 12"s

The answer to your question is complex. That is a highly specialized installation type used for SPL competition vehicles. The subs are built into sealed enclosures, but the gap between each array of subs acts like a quasi-port, creating a bandpass effect. Very peaky response, generally not something desirable for daily listening.

Alma Gates made this install type famous when her Bronco used it, and 64 PPI Pro 10's, to break the 170db level for the first time in history.

 

[audio_phill 10+ year member]

I am the audio guy of SW VA, lol. I build around 36 enclosures a year for others (more If I had the time) and 10 or so for me minimum, I do everything from SPL to SQ and design and setup full systems regularly. I have 14 enclosure orders on the table right now (all f which were chosen to be my design), lol. I probably own 60 woofers right now and none of them Spec this badly, lol.

 

[audio_phill 10+ year member]

The answer to your question is complex. That is a highly specialized installation type used for SPL competition vehicles. The subs are built into sealed enclosures, but the gap between each array of subs acts like a quasi-port, creating a bandpass effect. Very peaky response, generally not something desirable for daily listening.
Alma Gates made this install type famous when her Bronco used it, and 64 PPI Pro 10's, to break the 170db level for the first time in history.

Lol, theres nothing complicated about a 4th order alignment unless the person building is a complicated idiot, lol. Quasi-Port, lol. Take that talk over to the Quasi-6th order alignment builds lol.

 

[CoilBurner]

Nice answer...

If I were to port 8 of them in a wall, what frequency would I be best to try and tune for??? for daily

TO my understanding looking at the chart I posted, they preform best in 2.5 cubes net each?? Dont know how big to go with a common chamber

 

[audioholic 5,000+ posts]

Lol, theres nothing complicated about a 4th order alignment unless the person building is a complicated idiot, lol. Quasi-Port, lol. Take that talk over to the Quasi-6th order alignment builds lol.

Uh, a true 4-th order bp has a sealed chamber, and a ported chamber, that does not. lol?

 

[audio_phill 10+ year member]

lol, that chart is as wrong as wrong could be for volume requirements, lol. Download WinISD Beta and plug in those TSP's and see for yourself what it says, lol. These subs need "HUGE" enclosures to be daily driver subs with response flat enough to not be an earsore and a headache inducing nightmare, lol.

LinearTeam

WinISD Beta doesnt factor in Le so it doesnt show a true upper end roll off, but low end plots are reasonable accurate (usually within >2dB)

 

[audio_phill 10+ year member]

What r the subs mounted into then if thats not a sealed chamber?? lol.

 

[CoilBurner]

cmon no arguments in here, whats the best way to get good spl output outta these and sound good on rock in a wall

 

[audio_phill 10+ year member]

Then the open face style vented side basically functions as a high tuned port

 

[audio_phill 10+ year member]

Download WInISD and it'll take you 5 minutes to design the whole thing and show you the usable bandwidth as well as anechoic SPL.

 

[audioholic 5,000+ posts]

What r the subs mounted into then if thats not a sealed chamber?? lol.

I already stated they were mounted in sealed chambers, try to keep up with what Im talking about if you are going to be a critic.

Then the open face style vented side basically functions as a high tuned port

Its ironic, you laugh when I used the term 'quasi-port', but a couple replies later you say 'it basically functions as a port'. And then you think Im questioning if the subs are mounted sealed. //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif This is the first time Ive met you here, you aren't making a good impression. Your ego to intellect ratio doesn't balance out.