#35112 - 03/27/05 09:47 PM
Re: Max Extension via Port Plugging
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Desperado
Registered: 10/25/04
Posts: 688
Loc: peoria il
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i won't quit though,my next boxes are for jl 10w3d6 subs for my truck,they will be my first attempt for THE "harder to calculate 'rectangular' port",i'm not 'fraid,look forward to it!
wish 'wing' was closer so i could help!
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#35113 - 03/28/05 12:18 AM
Re: Max Extension via Port Plugging
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Deputy Gunslinger
Registered: 02/19/05
Posts: 9
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Several of the SVS subs have 3 ports, and plugging 1-2 ports is a method of lowering the sub's extension. BUT, as 'sraber' pointed out, there's a switch or knob on both the HSU and SVS that needs to be switched along with the insertion of the port plugs, which I did not realize. So now it seems apparent that something is being changed internally with the amp/electronics, along with the port plugs in these other subs-- a feature (switch) which is not available on the LFM-1.
So the big question is will I miss the 15-24 Hz range some of these other subs deliver?? I love the idea of 2 solid stereo Outlaw subs under $1K with free shipping now (with a couple of purchased cables). But will I wish I had that "wow" factor below 25 Hz in the HT???
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#35114 - 03/28/05 07:33 AM
Re: Max Extension via Port Plugging
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Desperado
Registered: 10/25/04
Posts: 688
Loc: peoria il
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i'll try to get into this again after work
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#35115 - 03/28/05 12:26 PM
Re: Max Extension via Port Plugging
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Desperado
Registered: 04/10/02
Posts: 1857
Loc: Gusev Crater, Mars
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The switch undoubtedly lowers the frequency of the high pass filter which rolls off bass below the tuning frequency. Some EQ changes might also be made by throwing the switch. The high pass filter prevents the driver from trying to reproduce frequencies below the tuning frequency which might damage it because of excessive excursion. Port plugging is what I have done with my JBL subs - they originally had 3 ports with a 25Hz tuning, and by plugging two of them, the tuning is around 12Hz. I lost efficiency which I made up for by using two subs per side instead of one. I hate when that happens.
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#35116 - 03/28/05 04:12 PM
Re: Max Extension via Port Plugging
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Deputy Gunslinger
Registered: 02/19/05
Posts: 9
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Soundhound--
You sound like you have some serious bass cranking! I would imagine you "experience" and hear a real difference between the 25Hz tuning and the 12Hz setup, yes?
It seems that more and more material being created out there is utilizing these lower freqs. Would that be your take too?
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#35118 - 03/28/05 06:28 PM
Re: Max Extension via Port Plugging
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Desperado
Registered: 10/25/04
Posts: 688
Loc: peoria il
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soundhound:
how much power do you have for the subs?each one have it's own amp,i assume?
i don't remember seeing those plugs in older pics.this a recent thing?
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#35119 - 03/28/05 06:35 PM
Re: Max Extension via Port Plugging
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Desperado
Registered: 10/25/04
Posts: 688
Loc: peoria il
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Originally posted by LaserMark4: Several of the SVS subs have 3 ports, and plugging 1-2 ports is a method of lowering the sub's extension. BUT, as 'sraber' pointed out, there's a switch or knob on both the HSU and SVS that needs to be switched along with the insertion of the port plugs, which I did not realize. So now it seems apparent that something is being changed internally with the amp/electronics, along with the port plugs in these other subs-- a feature (switch) which is not available on the LFM-1.
So the big question is will I miss the 15-24 Hz range some of these other subs deliver?? I love the idea of 2 solid stereo Outlaw subs under $1K with free shipping now (with a couple of purchased cables). But will I wish I had that "wow" factor below 25 Hz in the HT??? by having 2 subs,they will compliment each other,and with interaction with the room,i'd guess you should be down in the teens. my monitor sub had a switch(before i smoked the amp) for movies/music.monitor told me the movie setting gave a 3db increase over music mode,but could not elaborate on an eq change(i did ask)
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#35120 - 03/28/05 06:50 PM
Re: Max Extension via Port Plugging
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Desperado
Registered: 04/10/02
Posts: 1857
Loc: Gusev Crater, Mars
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Originally posted by painttoad: soundhound:
how much power do you have for the subs?each one have it's own amp,i assume?
i don't remember seeing those plugs in older pics.this a recent thing? They are in parallel on each side so the resulting impedance is 4 ohms. They are driven by a Soundcraft SA-1000 professional stereo 1000 watt amp that puts out 500 watts per side into 4 ohms. I do have another identical amp and for awhile drove each side by it's own amp, but I found that I didn't need the additional power. In spite of the port plugging, they are still quite efficient in the scheme of things because of the large cabinet size and 18" drivers. The tuning has always been the same. The pictures I have posted before have been with the grilles in place. The resulting response in-room is dead flat down to 10Hz, which is the lower limit of my RTA program (TureRTA).
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#35121 - 03/28/05 07:15 PM
Re: Max Extension via Port Plugging
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Desperado
Registered: 10/25/04
Posts: 688
Loc: peoria il
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for some reason,it seems like i remember big jbl subs being really efficient,10 hz has gotta be insane,i know how bad my eyeballs rattle in my truck,and my subs are cabable of 18hz but have never had it on an rta.i tuned my sealed boxes somewhere around 42 hz,but these things are going much lower,they do things my home(ported(2)) sub will not touch(rated at 22 or 25hz)!
if you can deal with metal and have no sensitive ears around the house try out DOPE:LIFE.tracks 1&6 have bass lines that would just have to be stupid loud on your system!don't stream it or use a burnt copy,the bass isn't there.trust me it would be worth the $15 just to have it 4 a demo.i used track 1 with 4 12's,in my truck,on the spl meter and hit over 150db!
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