Not enough Hi-Bass

turboconch2 · Postby **turboconch2** » October 25th, 2011, 11:58 am

I have a rf p3, the grey one, in a slot ported box, dimensions 24x14.5x14.5, L port 1.75 wide 23" total length running on a powerbass asa 1500.1dx. I listen to alot of old dub and i realise i don't get much of the high bass sometimes almost none. I know people say rockford is for lower bass but i want to know what can be done, should i build a new box, or change the sub. Its in a b11 with the sub facing to the rear of the vehicle. Tried to adjust the low pass and subsonic filter but not much difference noticed.

Postby **nervewrecker** » October 25th, 2011, 12:31 pm

you tried positioning the sub differently? facing forward or anything like that?

I feeling lazy to check the enclosure volume but it should be approx 1.75 - 2 ft^3 right?

when you say "hi- bass" what frequency range you talking about btw? I had to turn up the bass boost a bit from my head unit to compensate for the lack of bass within the 40 - 50hz regions on my rockford (p2 btw).

turboconch2 · Postby **turboconch2** » October 25th, 2011, 3:40 pm

Yeah I think it is around that region, i don't really get much bass for Buju- Lover's choice at all, the bass boost is a lil overwhelming i have it at +1 in my deck. Its about 2.2 cu.ft. BTW is this box too small?

MONGO · Postby **MONGO** » October 25th, 2011, 4:11 pm

on my calculator that box is 1.8cubic.ft @ 35Hz using 3/4MDF..what you can do is cut of 5 inches off the port length that will carry up the tuning to 38Hz..

wanted · Postby **wanted** » October 25th, 2011, 6:14 pm

dude you should try a new box, 2.5 cubic including speaker and port, use about 24 square inches of port 22 inches long.

Postby **nervewrecker** » October 25th, 2011, 7:36 pm

using 5/8" mdf internal dimensions should be:

20.75 " * 13.25" * 13.25" = 3642.92"^3 (divided by 12*12*12 + 2.1ft^3)

OR

1.729ft * 1.1ft * 1.1ft = roughly 2.09 ft^3

subtract port displacement 543.38"^3 or 0.314ft^3 & the piece of mdf separating the port from the insides 23 * 13.5 * 0.625 = 194"^3 or 0.11ft^3 & driver displacement 0.074 ft^3.
Thats 0.314 + 0.11 + 0.074 = 0.498ft^3

2.09 - 0.498 = 1.59ft^3.

Id say its pretty much built to manufacturers specification.

on bass box pro I tried my hand & got a tuning frequency of 39hz with the dimensions above.

Brian Steele · Postby **Brian Steele** » October 26th, 2011, 12:02 am

turboconch2 wrote:I have a rf p3, the grey one, in a slot ported box, dimensions 24x14.5x14.5, L port 1.75 wide 23" total length running on a powerbass asa 1500.1dx. I listen to alot of old dub and i realise i don't get much of the high bass sometimes almost none.

Sounds like a problem 60 Hz and higher. I don't think rebuilding the box is going to help, unless perhaps you change it out for a small sealed box designed around Qb~0.9 or so. What are you using to provide your midbass? 6.5" drivers in the doors? What x-over frequency are you using on the sub?

Another thing about "old dub" - recordings in those days were made with a bit more dynamic range and a bit less low bass than what you get these days. If you really want to bring out the best in them, you might want to think about using some post-processing, like BBE. I love my old dub, but I always turn on BBE on my deck when playing the tunes...

audiomagicians · Postby **audiomagicians** » October 26th, 2011, 12:54 am

its easier to tune a small box higher and a big box lower....... so what i would advise u to do... regardless of how u tune the box on paper when u put it in d car is a different story... blank off your slotted port and get a few lengths of 3inch or 4 pvc and cut different lengths... or if u good with woodworkin, cut a piece of board and insert it into the port move it up and down and play your music... see what sounds the best.. then u could modify your box to suit permanently...that is d tried and true method..

3stagevtec · Postby **3stagevtec** » October 26th, 2011, 10:02 am

1.8cu.ft tuned 40Hz..

:wink:

illest144 · Postby **illest144** » October 26th, 2011, 11:43 pm

Rockford subs are allrounders......to me i find you can try hw hard it will still respod to the lower freq...saw 4 10's p3 tuned t0 42hz or so...ting still plays like its on 36 or 38hz..lol...rockford never fails...

Postby **nervewrecker** » October 27th, 2011, 12:11 pm

btw, whats your processing like?
When I was using the mcd 360 I couldnt get much of anything above 40 - 50 for nothing. I even boosted the 50hz band on my head unit to +2 sometimes +3 with bass boost (45hz) at +2 & still most of the bass was in the 30hz regions.
When I took out the mcd 360 & sent the signal straight to the amps I got a little more of the thump from the sub (bass frequency was always in the lower 30hz range on the xover btw, anytime I raise it like to the high 30's & 40's the lower end was compromised a bit & it got a bit too boomy).
you tried beefing up your midbass btw? what you have for midbass?

turboconch2 · Postby **turboconch2** » October 27th, 2011, 3:07 pm

Thanks everyone for their responses. when i get some time i'll try the advice given.Nervewrecker, its a simple setup with the deck to the amps, a pio 4100ub, to a crunch gp150.4 then to 4 6" eminence for mids and for bass the setup given in the first post. sub setting on the deck 80hz.

Brian Steele · Postby **Brian Steele** » October 27th, 2011, 3:45 pm

turboconch2 wrote:Thanks everyone for their responses. when i get some time i'll try the advice given.Nervewrecker, its a simple setup with the deck to the amps, a pio 4100ub, to a crunch gp150.4 then to 4 6" eminence for mids and for bass the setup given in the first post. sub setting on the deck 80hz.

Hmm...What's addressing the frequency range between the subwoofer and those midrange speakers? Those 6" Eminence likely start cutting off around 200 Hz, if not higher (e.g. like if you have them mounted in a door, rather than a proper box).

3stagevtec · Postby **3stagevtec** » October 27th, 2011, 5:11 pm

Brian Steele wrote:
turboconch2 wrote:Thanks everyone for their responses. when i get some time i'll try the advice given.Nervewrecker, its a simple setup with the deck to the amps, a pio 4100ub, to a crunch gp150.4 then to 4 6" eminence for mids and for bass the setup given in the first post. sub setting on the deck 80hz.

Hmm...What's addressing the frequency range between the subwoofer and those midrange speakers? Those 6" Eminence likely start cutting off around 200 Hz, if not higher (e.g. like if you have them mounted in a door, rather than a proper box).

lol, that's been asked so many times before.. but most local 'gallery cars' or street beater etc really don't worry much for it.

Brian Steele · Postby **Brian Steele** » October 27th, 2011, 5:40 pm

3stagevtec wrote:lol, that's been asked so many times before.. but most local 'gallery cars' or street beater etc really don't worry much for it.

...except of course when they realize they're missing the "high bass"...

Postby **nervewrecker** » October 27th, 2011, 8:43 pm

well the problem has been identified right there.

maybe he can consider changing the midrange or adding a sub to it to cover the missing frequencies.

Brian Steele · Postby **Brian Steele** » October 27th, 2011, 9:19 pm

nervewrecker wrote:maybe he can consider changing the midrange or adding a sub to it to cover the missing frequencies.

Assuming that "upfront bass" really isn't a consideration here, he could try moving the sub LP filter up to 100 or even 125 Hz, or changing the cutoff slope to a shallower one if possible. The unfortunate thing though is that many of today's car audio subwoofers don't do upper bass frequencies very well (some old-school JBL 1200Gtis would come in handy about now

), and the box has to be really well built too, otherwise it will sound like real crap.