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kryptonitewhite

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Posts posted by kryptonitewhite

  1. I thought I was tuned to 14Hz in 22 cubes to begin with but I was at 16Hz with 20 cubes. I cut my 20" port down to 10 so i am at 21 cubes @ 20Hz now. Later I'll cut it down to 5" for a 25Hz tune. I hope I make a decision I'm happy with, then I can make the new box for the 22".

    FR curve 16Hz 20.5 cubes vs 20Hz 20.8 cubes vs 25Hz 21 cubes

    001FR.jpg

    nice thing about tuning below your desired range is ports are bad. group delay, turbulence, port compression, resonance... if you tune below where you center your play, yes you will lose SPL, yes you will have more excursion, but you will have less undesired effects as well not making the port do all the work.

    002GD.jpg

    no matter the driver, no matter the Fs, power handling, 1 super loose spider or 5 super stiff, super high BL with huge magnets or low BL with tiny magnets and top/bottom plate.... when you tune lower then you will have a hump up higher where power handling is down, excursion is up, and SPL is down. When tuning below 30Hz you will have an issue from 30-50Hz, you can see it clearly here from 18Hz-43Hz on the low tuned and 29Hz-43Hz on the higher tuned

    003maxpower.jpg

    same goes for SPL

    004maxspl.jpg

    IDK what the difference is between the "transfer function magnatude" and the "SPL" graph, both look like FR curves to me

    005spl.jpg

    the most important to me... power handling is generally more a mechanical problem than a thermal one if you have good clean power. It's mostly about bottoming out and clipping I feel. xcursion

    006xcursion.jpg

    resistance

    007resistence.jpg

    wind: I make a lot of it now that i shortened my port! I got hit in the eyes twice with sawdust I couldnt get vaccumed out.. saw it blow from inside the port strait at me up front... a good 4 feet! It BLOWS! We can feel port wind up front, but can't hear it. With the lower tune, we had very low excitation, little port velocity... and people were afraid 7.75" was too small. The lower you tune, I believe even more strongly now than before that port area requirement is lessened. A cone moving full excursion at 30Hz tuned to 30Hz moves a lot more air (twice as fast) as the same cone full excursion at 15Hz tuned to 15Hz.

    008turbullance.jpg

    of course as you lower tuning below your goal, not only do you lose the negative side effects, you lose your gain as well

    008turbullance.jpg

  2. build a t-line.... tune it to 11Hz, that way, an octave up or doun and you will be happy. you could play 1 cycle or 21. Is that low enough? I think you are pushing it just a bit. butt dud i wish you the best in your trials.

    how about I do that but bump it up to 22Hz though, then i am at the drivers Fs as well :D

    EDIT: only 13 feet 1/4 wavelength, I could pull that off

    Edit Edit: isn't 1 octave below 11Hz 5.5Hz?

  3. Power Handling

    Low Frequency Extension

    Flat Frequency Response.

    Pick two.

    Your kind of response is a bit like mine really. I like low frequency extension with a flat resonatic response. To my ears, there is only one enclosure that does so, and that is a horn. Then grab yourself a parametric EQ or a Graphic if you like cheating and EQ out any peaks or troughs in response. You should only need at maximum +/- 3dB. Any more and you need to redesign the enclosure. Try the BillFitzMaurice TubaHT, optimised for 15" woofers. I built a pair and loved the solid low frequency extension to 15hz.

    Cheers,

    Mick

    I prefer power REQUIREMENT :D

    low frequency extention and respomce that takes much much less power

    Ah, horns, TLs... I evolve ever so slowly, and some day I hope to be to that point :) I made my first TL a month ago with a 5" driver from a cheap walmart HT surround sound and a 5" cardboard pipe 8.5' long I got free from work..... learned a lot! 33Hz tune! Had to slap it right in the end as it was a perfect fot, though, so not 1/3rd to 1/5th the way in to eliminate nasty resonances.

    I don't want to do any EQing though, or port plugs... just keep on playin with my super low tuning, keep it large... so far I've done 15Hz, now I'll play with 20Hz for a few days, then bump up to 25Hz... good thing I decided to build a temporary box I can experiment with before I build the duece duece!

    I checked into the tubas a while back when i did the TL experiment, youtune has some vids on them

  4. What are your current box and sub specs by the way?

    If you're running that IB3 ported that could account for part of your unloading issues above 30Hz. I plotted it out in WinISD and see what you're talking about when you say you have to watch cone excursion in the 30-40Hz range.

    I have never tried a 15Hz port in my box (interchangeable ports) but I think I might try one tomorrow if I can fit it. I would be surprised if it unloads too bad at 30-40Hz

    I have been plotting and plotting and plotting all kinds of things for years with this setup in mind, older XXX's, 06' XXX's, SoloX18's, L7's, Tumults, Avalanches, all kinds of stuff... and when tuning below 20Hz, excursion is usually a problem whether an "spl" driver, a "SQ" driver, or what have you... "SQL". The lower you tune, the narrower the bandwidth where port gain and excursion are effected, as well as the steeper the effects of unloading... I'm interested in what you think if you drop a 15Hz tune in! I hope you can play the 10 songs I have on my list, I'll look it up and post it....

    So my box was a slap together temporary build, and I was so happy with it that I almost decided to mkeep it, but the 22" isn't gonna fit... I have to keep 1 seat down as it is to keep the sub from smackin it, and I am already way underpowered and seldom reach high excursion as it is. I'm gonna try to bump it up to 25Hz to experiment before making a permenant box.

    I am 38" tall in the front, 32" in tha back, 30" deep on the bottom, and 28" deep on top, 42" wide with a 20" port 7.75" in diameter.

    38 + 32 = 70/2 = 35" tall average, 33.5" internal height

    30 + 28 = 58/2 = 29 average 27.5 internal depth

    42" wide 40.5 internal

    33.5 X 27.5 X 40.5 = 37310.6/1728 = 21.59 cubes before displacement... I WAS WRONG!!

    7.75" X 19.25" long = 47 area x 19.25 = 907.6 cubes/1728 = .525 port displacement + .22 cubes sub disp = .75

    21.59 - .75 20.8 cubes! round to 20 cubes

    20 cubes 7.75" x 20" = waiting for IB3 18 single 2 plug in for winisd

  5. I bumped it up to 20Hz... I have mixed feelings so far. If I had proper power it would be easier to tell. Overall, I think I liked the sound better at 15Hz but I am "safer" with less exursion, but it actually seems quieter not louder. Bass I Love you blows a shit ton of air now at 18Hz though, things seem a bit tighter, more defined, punchier... yet more clouded, more added to it and muddled. Seems kind of contradictory, but I'm gonna go play some more, and after a few days I'll bump it up again to 25Hz.

    before: 20" 15Hz

    DSC_0001-2.jpg

    cut almost all the way around at 10" then slit both sides and took 1/2 a side out

    DSC_0003-2.jpg

    other side out too, 10" for 19Hz now

    DSC_0005-2.jpg

    DSC_0006-2.jpg

  6. I didn't read the rest, just the first topic.

    I love ultra lows, I think its neet to play 10 to 20 hertz. Its just neet to me but I have not and would never think of trying to do it ported.

    All my personal installs are sealed box setups even though I could be really loud with my stuff if I ported it.

    I would love to have my 4 10s in 4 spereate 1 cubic foot enclosures.(One box 4 sections sorry) but the best I can do is .7 to get all 4 in there.

    Its still pretty neet at 20 hertz.

    and that would be tight and snappy as well :P

    Im not going for < 20, I'd say 18Hz at the lowest cuz Bass I Love you is so much fun.... but I'll say I am going for 20Hz-30Hz

  7. How do you figure?

    cuz Scott said so. I didn't say a 22" cone is equal to the Sd of 2 18's.

    Scott is purposely making the IB3 22" almost a drop-in substitute for 2 18" IB3's. He is increasing Xmax as well. He's also trying to do this with the cost as less than 2 18's.

    And, he's doing an auto 22" ... whether that is going to be a 22" BTL or not I do not know, because I am into the IB3 series, but if ya email him he'll prolly give you some info.

  8. I'm gonna have to disagree with this statement....its about the enclosure design and loading environment.

    for my old school JL 15W4 the excursion graph in my enclosure said I should have been bottoming out badly with 200-300 watts...The enclosure was 4.3 cubes tuned to 40Hz with 112.5 sq in of port area...I gave this sub all my 800 watt rms amp had daily with no problems....No SSF either. played down to 30Hz with no excursion problems.

    On the WinISD excursion graph of this sub with 800 watts the sub should have smashed the former to hell.

    ya, I'm guessing this is because your car became part of the enclosure, so you were tuned lower.... plus cabin gain/pressurization?

  9. I can drop well below my tuning.....I'm in a 4 door blazer....I can play below 22hz full tilt without a subsonic....I'll make a video....but if I open my rear hatch where my port is loading of the tailgate they being to unload at about 25hz...but only then.....and how often am I going to be driving down the road with my tailgate and rear window open lol.

    I remember in HS some guy had a Bloupunkt 10" in bandpass and you couldn't hear it outside, so he actually made a prop stick so he could drive around with his hatch open 2" so you could hear it LOL

    so is it loading, or is it also effectively elongating the port, thus tuning it lower?

  10. So my box was a slap together temporary build, and I was so happy with it that I almost decided to mkeep it, but the 22" isn't gonna fit... I have to keep 1 seat down as it is to keep the sub from smackin it, and I am already way underpowered and seldom reach high excursion as it is. I'm gonna try to bump it up to 25Hz to experiment before making a permenant box.

    I am 38" tall in the front, 32" in tha back, 30" deep on the bottom, and 28" deep on top, 42" wide with a 20" port 7.75" in diameter.

    38 + 32 = 70/2 = 35" tall average, 33.5" internal height

    30 + 28 = 58/2 = 29 average 27.5 internal depth

    42" wide 40.5 internal

    33.5 X 27.5 X 40.5 = 37310.6/1728 = 21.59 cubes before displacement... I WAS WRONG!!

    7.75" X 19.25" long = 47 area x 19.25 = 907.6 cubes/1728 = .525 port displacement + .22 cubes sub disp = .75

    21.59 - .75 20.8 cubes! round to 20 cubes

    20 cubes 7.75" x 20" = waiting for IB3 18 single 2 plug in for winisd

  11. It's Actually 25hz.

    I looked again after reading your post.

    youre a fucker! youre just sayin that cuz that would be so perfect, as possibly low as possible if I tuned to 25Hz and had a 2500.1 :P EDIT: did i just say possibly possible?

    hahahahaha

    thanks man, I'm gonna hold my breath and start cutting as soon as I can plug the IB3 into WinISD ( I did it manually a few times and its one of the tricky subs that won't auto-plot vented cuz it doesnt have enough specs listed)

  12. ever listen to paul wall internet goin nutz ?

    it's hard to keep up with all the posts of what everyone says is low, I've been tryin to download all I can but it's hard to keep up, and, everyones opinions are different, everyones systems are so different... I almost wish I had an all inclusive list that is done with spectrum analyzers, BUT, sometimes I wonder about those, cuz some songs that seem lower than others dont match up with what the analyzer says.

  13. From what I can understand of your post it sounds like you're looking for a design that sounds "good" on 99% of the music out there, but then completely destroys the lows as well.

    I think you may be able to better tune your desired output with a 6th order bandpass box since you're looking for something fairly specific.

    Just remember you have to make sacrifices somewhere. There is no such thing as a "perfect" enclosure, because it's all relative to your preferences. If you NEED to peak at 20-30Hz, you're gonna have to accept that most music will play at a lower level.

    Couldn't have said it better myself, believe me I've been trying for years! I have considered 6th and 8th, taking away completely from the highs adding to the lows... maybe someday, for now I'm gonna stick ported though. I totally accept that I will lose out from 30Hz on up by getting the mad lows, I have been trying to explain to people for years that I am totally fine with that... but I am worried about excursion and bottoming out... cuz I can crank anything sub 30, but I have to be really careful and stay tense ready to drop the knob for 30-45Hz... and I don't want that. The whole point to me tuning so low is I love low, and I don't want to worry about 1 song out of nowhere being too low. I think raising up to 25Hz otta solve my problems, IF I will still be OK when something plays below that.

    I love this:

    " From what I can understand of your post it sounds like you're looking for a design that sounds "good" on 99% of the music out there, but then completely destroys the lows as well.

    That says it all perfect!

  14. mine being @28hz would play hard from 40hz to 16hz but can go all the way down full power. my ssf is all the way down, which is 10hz and i dont unload anywhere. my port is up against my hatch, so i believe it helps load the port more giving me my performance so well down real low.

    I just don't understand that... I have HUGE excursion at 18Hz during Bass I Love you, and I am tuned to 14Hz! So how can you go that low? I have an 18" with less than a grand of power!

    I have been playing with the seat up and down that is in front of my port, I thought mine would "load" against it, but instead it is blocking or restricting airflow so I think I get more excursion instead of it effectively tuning lower and getting more gain via loading

  15. you'll be fine tuning 25hz, even if you want to play 15, just be careful on the volume

    my 43hz tune will drop to 28 at basically full power with no weird side effects/unloading, it may go even lower, i just dont have any music (yes i listen to music, not bass cd's, its a cool thing to do with a stereo imo) that drops lower than that, and even that is just one section of one song. 29hz like in "i love your girl" or something like that is played with similar ease, but then again my peak is definately high 30's/low 40's somewhere

    the kicker amp, i'd suggest something else. unless you have your heart set on that log back there, if you want to go low its not the way, that ssf is locked in there. rockford t2k, the new t-2500 thats coming out, which would make you the coolest guy on the forum, atleast until meade straps 8 in his ride just to be the coolest guy ever..

    I'm gonna go out and cut the port today.... but 1st can anyone get me the IB3 single 2 ohm WinISD

    http://www.hometheatershack.com/forums/att...fi-ib3-18s2.wdr

    http://www.hometheatershack.com/forums/diy...-pro-files.html

    I'm going out to re-measure to get airspace, as soon as I have the IB3 file I'll plug that back into winisd and figure the 25Hz tune

    So why do subs in-car go so much further below tuning? I can't see more than 10Hz being OK with full power!

    So the 25Hz SSF will be an issue???

    the t2k... is that the same as the t15k... large capacitance made for huge power burps and short plays? Acts like a defibrillator?

    I am looking for something less than $500 that will do a solid 2500 watts with high efficiency. I'm thinking of getting rid of 3 of my 6 red tops, cuz they're heavy as hell.

    What I would really like is a used KX/ZX 2500.1 for $300-$400, Rockford is fine, I'd maybe consider another Hifonics rated 3000 so that I still get at least 2500

  16. Nope it's 27hz.

    OK, I'm gonna do it... I'm gonna chop some port off and raise it from 15Hz to 25Hz on my temp box so I can rebuild for the 22" cuz Scott emailed the other day and I got more info. I am scared to death. I am not sayin I do not believe you, but, I want to make sure before I bottom out HARD. This song sounds like it goes all the way to the bottom lines of no longer being sound and into infrasonics. My ears are probably shit, or the program I use to decode it (my brain v.02). So the program says it's 27Hz, and if it's right, then me tuning to 25Hz (I will actually do 24 for leeway, I am actually tuned to 14 Hz right now nobody knows it but I round off airspace to be lower and I round of tuning and say it's higher... I am at 14Hz! ) will be perfect!

    So anyone with good ears out there? Can you play test tones from 20Hz-30Hz and decided exactly which test tone sounds closest to the low note on Willie????

  17. I am not a fan of the ultra lows and I don't build for that, but why not tune in the mid to upper 20's and concentrate your effort on upgrading the electrical for even more power?

    I have the Big 3 done and I have 6 Optima Red Tops. I will get a HO alt when I can, BUT, I only have 1000 watts now and I won't use but maybe 1/2 of the 2500.1 when I get it... just super clean power with a ton of headroom when I want it. I'll prolbably do a 25Hz tune. The SSF on the KX and ZX are NON-defeatable, fixed @ 25Hz... correct??

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