something WEIRD about the movement in my subs!! READ

[vehementSPL 10+ year member]

Ok.... Perhaps I am under the wrong assumption here but I thought the woofer moved the least around its tune and then moved more the further away it gets from the tune and then typically roughly 15hz above the tune then excursion starts slowly dropping off. I decided to play with some of these junk speakers we have because they seem pretty loud so I put them in an extra box I had laying around. box is 8 cubic feet tuned to 38ish . ok around 38hz the subs move a decent amount but when you get at 48hz they lock....... obviously I am missing something here that I thought I knew and I for sure don't know

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[MakeshiftAudio 10+ year member]

Boxes are fine tuned to specific driver features to get their tuning. One does not just build a box and tadah, no matter what sub, it's tuned to that frequency.

 

[vehementSPL 10+ year member]

I never stated peak output. I said BOX TUNE. and box TUNE is 38hz. the volume peaks at about 48 to 50hz. the least cone movement at 48hz

 

[528hz 10+ year member]

What does it do at say...30-35 hz? What subs are they?

 

[MakeshiftAudio 10+ year member]

Oh. Hmmm... Thinker in Winisd to answer your questions regarding excursion compared to spl compared to tuning. That would be the most beneficial way.

 

[bass_lover1 10+ year member]

Boxes are fine tuned to specific driver features to get their tuning. One does not just build a box and tadah, no matter what sub, it's tuned to that frequency.

Ummm, you're an idiot.

When you build a ported box, the function you use to get the tuning frequency, has absolutely NOTHING to do with what sub is going in it. Box volume, port area and length, are the key factors. Not what driver you put in it.

Humidity, and the weather around you, will probably change your tuning frequency more than using different speakers.

 

[Immacomputer 10+ year member]

One does not just build a box and tadah, no matter what sub, it's tuned to that frequency.

Wrong.

Your enclosure is tuned to 48hz not 38 like you think. You ****ed up on your calculations somewhere (which isn't surprising).

 

[Xprime4 10+ year member]

lower freq got natural higher and less frequent excursion. Higher need less but the cycle are faster.

There's nothing wrong here

/topic

 

[Immacomputer 10+ year member]

lower freq got natural higher and less frequent excursion. Higher need less but the cycle are faster.There's nothing wrong here

/topic

In a ported enclosure, the speaker will not move much at all at and around tuning. If it moves less 10hz above your expected tuning, then the tuning frequency is off, especially when you have decent excursion around your expected tuning.

My current sub moves less at 22hz than it does at 60hz.

 

[Xprime4 10+ year member]

In a ported enclosure, the speaker will not move much at all at and around tuning. If it moves less 10hz above your expected tuning, then the tuning frequency is off, especially when you have decent excursion around your expected tuning.
My current sub moves less at 22hz than it does at 60hz.

are we talking about ssf? sure the ssf will cut the excursion under where its been set . Otherwise, i don't know.

Snoopdan mix of Love story makes my woofer wangs alot at 17hz even if i'm tuned at 36hz (aq subs) SSf is set in the low 20ish

 

[bass_lover1 10+ year member]

are we talking about ssf? sure the ssf will cut the excursion under where its been set . Otherwise, i don't know.
Snoopdan mix of Love story makes my woofer wangs alot at 17hz even if i'm tuned at 36hz (aq subs) SSf is set in the low 20ish

No, what he's saying that at the tuning frequency of a ported enclosure, cone movement will be at it's lowest. Below tuning, the speaker will unload on it self, almost as if it were in a free air environment, and above tuning, the driver acts very similarly to a sealed enclosure.

 

[Immacomputer 10+ year member]

are we talking about ssf? sure the ssf will cut the excursion under where its been set . Otherwise, i don't know.

Of course not; I'm talking completely open and unfiltered signal from 1-80hz sent to my sub. The reduced cone movement at 22hz is due to the enclosure design.

There will be a point of high acoustical impedance (resonance) behind the driver and the cone movement will be reduced in any resonant enclosure. Sealed systems have the opposite since the driver is the only resonant system. Only in this case, cone movement is at a max at resonance instead of a minimum.

 

[jdawg 5,000+ posts]

are we talking about ssf? sure the ssf will cut the excursion under where its been set . Otherwise, i don't know.
Snoopdan mix of Love story makes my woofer wangs alot at 17hz even if i'm tuned at 36hz (aq subs) SSf is set in the low 20ish

you sure it 'wangs', you mean move or loud? You shouldnt really hear 17hz. Also just because he says its a 17hz tone doesnt mean its 17hz ONLY. Also a ssf isn not a 100% cut on anything under what its set at, its a gradual roll off.

 

[Xprime4 10+ year member]

ok i think i understand. I'll check by myselft as soon pretty soon. I've notice the unloading of the box at freqs under the tuning, but never the lower excursion right at tuning freq

 

[IDSkoT 5,000+ posts]

you sure it 'wangs', you mean move or loud? You shouldnt really hear 17hz. Also just because he says its a 17hz tone doesnt mean its 17hz ONLY. Also a ssf isn not a 100% cut on anything under what its set at, its a gradual roll off.

This. Acts more like an Xover.

 

[Xprime4 10+ year member]

you sure it 'wangs', you mean move or loud? You shouldnt really hear 17hz. Also just because he says its a 17hz tone doesnt mean its 17hz ONLY. Also a ssf isn not a 100% cut on anything under what its set at, its a gradual roll off.

all I hear is the box unloading. I asked Snoopdan what sweep he was using on that part of the song and he tells me 17hz.

 

[SicAudio 5,000+ posts]

In a ported enclosure, the speaker will not move much at all at and around tuning. If it moves less 10hz above your expected tuning, then the tuning frequency is off, especially when you have decent excursion around your expected tuning.
My current sub moves less at 22hz than it does at 60hz.

Am I missing something? 22hz is a slower frequency than 60hz is 22 cycles per second vs 60 per second ? right? so wouldn't anything do that, regardless of the enclosure?

please enlighten me cuz now I am totally confused lolz.

 

[jdawg 5,000+ posts]

all I hear is the box unloading. I asked Snoopdan what sweep he was using on that part of the song and he tells me 17hz.

ok i get it , like i said its cause a ssf is a gradual roll, so you will still pick it up

 

[bass_lover1 10+ year member]

Am I missing something? 22hz is a slower frequency than 60hz is 22 cycles per second vs 60 per second ? right? so wouldn't anything do that, regardless of the enclosure?please enlighten me cuz now I am totally confused lolz.

He means the suspension is moving less, not that it's moving slower.

And no, 22hz isn't "slower" than 60hz, you REALLY need to go back to 6th grade science class.

To clarify, because my statements sound somewhat contradictory:

Yes, at lower frequencies, the suspension is moving slower, when relative to higher frequencies, however that does NOT mean that 22hz travels slower than 60hz. The speed of sound is a constant, and changes depending on through the medium which sound travels.

 

[SicAudio 5,000+ posts]

so then this is wrong? :

One hertz simply means "one cycle per second" (typically that which is being counted is a complete cycle); 100 Hz means "one hundred cycles per second", and so on.

that tells me that 1 Hz is moving slower than 100 Hz