tuning tip question

Discussion in 'Car Stereo Amplifiers' started by subpounder101, Mar 31, 2011.

  1. subpounder101

    subpounder101 Full Member

    Hello, i'll make it to the point.
    I have a MA HK1000D running at 4ohms.
    Frq Responce 10hz-350
    24db Low Pass 50hz-350
    24db Sub Sonic 20-50hz
    bass boost 45hz 0-18db
    Has a 5V input from a Panasonic 8300U.

    For this is a Aw152T Audiobahn in a Vented(4th order) 3.0cbft tuned at 30hz which responce frq hz is 22hz-700hz.

    I enjoy rock music from classic to death metal.(bass music and rap is all expected to bump due to digitally being made)

    any good suggestions on tuning, i have what i think is 30"hz on subsonic and 50hz for lpf at about 10db+bass but for some reason I just feel im missing music, specially after a recent test on a song 60-20hz sweeps it was peaking around 41hz and making no sound around 26ish which scared me of voice coil damage...... The LPF on the deck EQ is set at 60hz and HPF is set at 130hz.
     
  2. steve

    steve Full Member

    If you listen to mainly rock,i believe you'd be happier with a sealed box(something to consider). Anyway, if you're subsonic is set on 30
    hz you are not going to hear much of anything around 26hz .

    Since you listen to rock say vs classical, i wouldn't worry about 20 something
    hz. I suggest you play with the LPF between 80-100hz and find what
    sounds good to you.
     
  3. soulfly

    soulfly Full Member

    Probably a personal preference, but i listen to Rock,Metal and even Jazz. After 2 years on Sealed boxes between several types of subs, I found i preferred a Ported box around 34hz or so.

    At 4ohm's, your running approx. 500 watts. sub might slightly be underpowered.
    i'm thinking your 30hz tuning may be too low. That tuning is closer to a sealed sound and less efficient.(in case your wanting the subs louder) 80hz LP might help out your Midbass speakers and fill a potential gap better. Subsonic filter on so you won't hear below that anyway...but i don't think Metal music goes much below 40hz anyway, So i kinda doubt your missing any realistic low frequencies, likely any gaps your hearing maybe in the upper range from your components/coaxials.

    don't worry about below 30hz sounds and input your specs into WinISD program so you can get a rough visualization of your sound and see how tuning or sealed will help or hinder you.
     
  4. subpounder101

    subpounder101 Full Member

    ok very interesting. Now I got another question lol...

    Say if you pick up a pre-fab box that has the cb. ft you need for your woofer but the box is tuned at 32hz, but the woofer enclosure specs for that size box says 36hz. Can you change them with out damage being done or;
    i would, kind of maybe.... :) like to tune higher like around 43"ish"hz or trying to get max SPL and drop all SQ, but im come into the personal question if I can tune different and not cause any damage.

    Because with the last box i had which was 3.0 after port displacement and came to 2.87cb. ft. with the subwoofer in, tuned too 30"ish" and LPF on 90"ish" sounded great for example: Basstronic -Bass I Love you very clean low deep hits but **** for SPL, Judas Priest - Painkiller picked up the double bass clean and crisp, Shaq - Can't Stop The Reign sounded like normal rap bass lol , but Van Halen - I'm The One sucked ass which made me cry... but overall this lead to the top wall and back, and the port wall seams breaking apart and created horrible port noise, but after over looking the math the box was too small so i understand why it took a **** :p
     
    Last edited: May 13, 2011
  5. subpounder101

    subpounder101 Full Member

    no help on this for real :( a simple yes or no you can't do that will work....
     
  6. steve

    steve Full Member


    Yes you can change the box tuning, I'm not sure what damage you're talking about though. being a prefab box, the're well, not usually built very well. At anyrate when you change the port size the VB will change also, what you need to know is how will the sub(s) preform in the box. A poorly built/designed box is just asking for trouble.
     
  7. subpounder101

    subpounder101 Full Member

    ty steve, well the damage im "scared" of is over extending the driver, too much/less power for the box size tuning change"" because of requirements not matching and than anything else that I may not even be aware of.

    The box is prefab but not like been made 10 years ago sitting on a self in a store prefab, its a prefab design that used for generic woofers"" as he stated, you order and he builds its. I've seen pics, its very nice so far since ive been waiting about two weeks now lol, it's all 3/4 USA MDF with a 1" Front Baffle, the port structure is Labyrinth with dato joints and doubled caulked, glued , with perfect 3.2 cb.ft after port displace and this woofer takes .23 and i did the math my self after he told me the size and it was key on unless 1728 is no longer the golden rule:) and even after all the $$ i still might un carpet it, and do support screw ever 6".

    So over all even if its built tuned to 32Hz, I could tune my amp sub sonic to "" 43-45ish HZ to see how I like the SPL output and or maybe 36HZ(what the manual calls for) for a SQ/kind of SPL and this wont over push pressure in the box to put more force against the back of the driver or put extra stress on the seals of the box or w/e?

    I might add as well, I was thinking in the future to buy a salve HK1000D to run 1000RMS@4ohm at 17V to this 650RMS woofer.
     
    Last edited: May 17, 2011
  8. steve

    steve Full Member

    Well if the box is tuned for 32hz uping the sub/s filter is'nt going to make it a spl box. At 32hz your looking at more SQ, thats not to say you wont have desent output it's just that the tuning and size of the box is what makes it a spl set-up. Changing the subsonic filter is just going to make the cut-off freq higher not louder, of corse you may have some gain due to the amp not trying to reproduce lower freq (like if it was set at 20hz).For the subs being damaged,as long as they are rated to handle the power and remain (loaded) in the box there should be no problem.
     
  9. subpounder101

    subpounder101 Full Member

    ty steve, I guess i'll stick with a SQ for tuning around 30HZ Sub sonic and 90LPF and just wait for a new car to re build a new box for SPL output and buy a new sub woofer for it all, Maybe i'll re do the enclosure i got laying around with a old JBL P15(very nice woofer if u never seen one).
    Well time to get some weather stripping and polyfill for the new box :) thanks again for the help
     
  10. subpounder101

    subpounder101 Full Member

    ty soulfly, and fyi thats a great band has a nice sounds. Im just gonna stick around 36HZ which the manual calls for, and play with my LPF and the Deck EQ so i can get the sound i'de like which is just trying to get Van Halen to bump which wont be easy compared to other rock music. I had this woofer in a sealed box first, dual sealed, and than i had dual 15" in a open chamber box( that was loud had JBLBP1201.1 running each 15") through the years, it sounded best to me in a ported box. Just to bad it took 7 years and this ported box that just blew apart killed my other AW152T voice coil and part of the spider, but this one left over is all most 10yrs old and still hitting hard :)