low notes = sub excursion = no bass?

[Bobby322 10+ year member]

My sub plays fine except when it hits the lower notes. I get a lot of excursion and i think its moving quite a bit of air, but its not bass loud. Its probally a setting on my amp isnt right, which would it be? LPF?

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[twistedchild420 5,000+ posts]

Box tuned too high

 

[I Like Waffle]

Box tuned too high

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[Bobby322 10+ year member]

box is at 32 hz. it needs to be lower???

 

[bladebarrier 10+ year member]

box is at 32 hz. it needs to be lower???

Yep, your woofer is just flopping around in free air once you go below your tuning frequency. It's also a good way to rip apart your sub.

In order to properly reproduce the lowest frequencies you need a very low tuning, or a sealed box.

 

[Bobby322 10+ year member]

so the frequency of the note when it hits is lower than 32 hz? so I cant play anything lower than 32hz without this happening?

 

[amartin_72]

Might have been calculated wrong. Do you have the dimensions of the box and the port?. Should do OK with a 25hz subsonic

 

[bladebarrier 10+ year member]

so the frequency of the note when it hits is lower than 32 hz? so I cant play anything lower than 32hz without this happening?

At Fb your woofer is optimally damped, in a ported enclosure, so the woofer moves very little, it can take a crap load of power (mechanically), and the port does most of the work.

As soon as you go below Fb however, your woofer starts to act as if it's in free air without any box at all. It begins to flop around and loses significant power handling capability. This is why sealed boxes are generally used for the absolute lowest frequencies.

To be quite honest, there's not much real music below 30hz, so what are you trying to play that's creating an issue? 32Hz is probably a fine tuning for most music, to keep a mix of sound quality and spl.

 

[Bobby322 10+ year member]

there are quite a bit of songs that do it. a few notes in "Put on", "love for money", and acouple remixs from snoopdan

 

[bladebarrier 10+ year member]

there are quite a bit of songs that do it. a few notes in "Put on", "love for money", and acouple remixs from snoopdan

I just listened to "Put on", on my reference headphones to get an idea of how deep it is. There's a very low note in there. It could be below 30hz.

So, I guess you need to decide how important it is. Drop your tuning very low, which may require increasing the box size considerably, or swap to sealed, or just accept that ported isn't really for super deep bass unless you use a huge, low-tuned cone/box.

 

[audioarsonal 10+ year member]

There are alot of songs that play or drop below the 30 hz freq.Its just most people don't tune that low with a ported box due to the tuning limitations.If you run a sealed box you will notice a lower cut off but overall output will be less then a poted box

 

[bladebarrier 10+ year member]

There are alot of songs that play or drop below the 30 hz freq.Its just most people don't tune that low with a ported box due to the tuning limitations.If you run a sealed box you will notice a lower cut off but overall output will be less then a poted box

I don't know. 30hz and below is pretty uncommon. Of course it depends on what you listen to. Very few instruments, aside from pipe organs, can go that deep, or would ever do so on a regular basis. Sure bass cd's can get down there, and some hip hop, but it's not the norm for actual instruments. Hell, Enya has songs that get down close to 15hz, but you can barely hear the real sound (more like it's a feeling of air movement as much as anything).

Of course, if all you listen to are bass cd's, you should prepare your tuning for as deep as you can, if you like the ultra-low, synthesized notes.

/This message was brought to you by someone that prefers sealed boxes or very low tunings, in case it seemed like I don't see a need for low end extension. I just don't think that much common music ever gets that low.

//You have to go out of your way to find bass that deep. I do go out of my way to do it, though.

 

[Bobby322 10+ year member]

well i have a truck and dont have a lot of room, so I guess a cant tune too low because I would need more space. Im guessing its just a low note and not my settings messed up. I dont want to lose the SPL from going ported to sealed.

thanks

 

[Xprime4 10+ year member]

lower is also harder to "ear" coz in the end, it's just air mouvement.

In the last 12 sub setup i had, the fiQ and they tc-9 are the only one that let you "ear" to low-low end bass. Most of the sub/enclosure combinaison won't be able the be flat under 30hz...

btw there's alot of "hidden" content down there... depending on what you listen to.

your best bet is oversize box and low tuning

 

[KyleBechtold 5,000+ posts]

playing under tuning.. there is not much left to hear under 30 more just feel