im happy with my JL Audio 10w7, but...

[Aharami]

i think its too boomy. I was looking for tight base. I dunno if its the enclosure I built, or whether its cuz the 10w7 i bought was used...
the enclosure I built is more or less to JL recommended specs: 1.32 cu ft internal volume. JL recommends 1.25 cu ft internal vol without taking into consideration the sub displacement. Since the cone displaces .09 cu ft, i made the total internal vol of the sub as 1.32 - 1.34 cu ft. Its a sealed box.

Now im thinking maybe I should've made the box a bit smaller - maybe 1 cu ft total internal vol (so after cone displacement, I'd be left with .91 cu ft internal vol)

Would the base response get tighter if I reduce the size of the box? Friend has an Alpine type-X and he claims that his sub got a lot tighter after he reduced the enclosure volume.


Also I should mention that I JUST finished putting it in and hooking everything up. So I havent had the chance to play with the settings on my amp. I have an Alpine MRD-M1005 powering the 10w7.

 

[spidey07]

put some poly fill in the sub. That will help.

 

[Aharami]

Originally posted by: spidey07
put some poly fill in the sub. That will help.

correct me if Im wrong, but doesnt polyfill "make the sub think" that the internal vol is actually bigger than it is?

the question really is what kind of enclosure produces tighter, more accurate base response? Does the base get more boomy as you increase the internal vol?

 

[glen]

The larger the box the better.
The best is no box at all, use the trunk as the enclosure.
The next thign to do is anylyse the system with an RTA.
Then, you can probably fix it with a pair of mono EQs, like Audio COntrol EQTs.

 

[Howard]

Originally posted by: Aharami

Originally posted by: spidey07
put some poly fill in the sub. That will help.

correct me if Im wrong, but doesnt polyfill "make the sub think" that the internal vol is actually bigger than it is?

the question really is what kind of enclosure produces tighter, more accurate base response? Does the base get more boomy as you increase the internal vol?

Adding stuffing is the equivalent of increasing enclosure volume, which reduces the Q of the box (Q of 0.5 = critically damped, Q of 0.7 = maximally flat response, anything higher leads to peakiness).

I'll put up some graphs in a bit.

EDIT: The "room gain" of the car will make the bass sound much louder and might be contributing to the boominess.

http://www.rootminus1.com/howard/pics/jl10w7sealed.gif

 

[James3shin]

Originally posted by: spidey07
put some poly fill in the sub. That will help.

adjust your eq settings and if that doesn't work, go with the fill.

 

[James3shin]

actually, what do you mean by "tighter bass"? Are you looking for more isolated thumps?

 

[Aharami]

Originally posted by: glen
The larger the box the better.
The best is no box at all, use the trunk as the enclosure.
The next thign to do is anylyse the system with an RTA.
Then, you can probably fix it with a pair of mono EQs, like Audio COntrol EQTs.

better is a subjective word. please explain what you mean by better? better as in tighter, more accurate response? I listen to a lot of Trance with faster beats than what you'd find say in Rap or Hip Hop. For Rap and Hip Hop I guess the base response would be fine since the beats are spread apart, but with the music I listen to, I feel I need tighter base response

 

[glen]

Originally posted by: Howard

Originally posted by: Aharami

Originally posted by: spidey07
put some poly fill in the sub. That will help.

correct me if Im wrong, but doesnt polyfill "make the sub think" that the internal vol is actually bigger than it is?

the question really is what kind of enclosure produces tighter, more accurate base response? Does the base get more boomy as you increase the internal vol?

Adding stuffing is the equivalent of increasing enclosure volume, which reduces the Q of the box (Q of 0.5 = critically damped, Q of 0.7 = maximally flat response, anything higher leads to peakiness).

I'll put up some graphs in a bit.

You are absolutely right about the Q.
Folks also equate this with the boomey or not boomey sound, so you are right again.
Did you know that in controlled tests, there is no study that showed a human as being about to hear the differences in Q.

 

[Aharami]

Originally posted by: James3shin
actually, what do you mean by "tighter bass"? Are you looking for more isolated thumps?

yes

 

[Dunbar]

I'd try the smaller box.

 

[glen]

Originally posted by: Aharami

Originally posted by: glen
The larger the box the better.
The best is no box at all, use the trunk as the enclosure.
The next thign to do is anylyse the system with an RTA.
Then, you can probably fix it with a pair of mono EQs, like Audio COntrol EQTs.

better is a subjective word. please explain what you mean by better? better as in tighter, more accurate response? I listen to a lot of Trance with faster beats than what you'd find say in Rap or Hip Hop. For Rap and Hip Hop I guess the base response would be fine since the beats are spread apart, but with the music I listen to, I feel I need tighter base response

Google "infinate baffle" and you will get your fill of information

 

[arcas]

1.3 cuft seems awfully large for a sealed 10" enclosure. Are you sure that wasn't the recommendation fora ported enclosure? I have a 10" Image Dynamics sub in a 0.55 cuft sealed enclosure.

 

[Howard]

This is a bit of a stretch, but do you know the frequency of the bass line of the stuff you're listening to? Or does it vary?

 

[James3shin]

accurate response = fidelity? Go with a smaller box if you're into trance. Oh as someone mentioned, about the dimensions for the ported vs sealed...sealed is what people seemed to like when i installed for trance listeners.

 

[Acanthus]

Originally posted by: Aharami

Originally posted by: James3shin
actually, what do you mean by "tighter bass"? Are you looking for more isolated thumps?

yes

adjust the EQ

if that doesnt work

you need mids.

 

[Howard]

Originally posted by: Acanthus

Originally posted by: Aharami

Originally posted by: James3shin
actually, what do you mean by "tighter bass"? Are you looking for more isolated thumps?

yes

adjust the EQ

if that doesnt work

you need mids.

Maybe he just needs to reduce the gain on the sub amp.

 

[Acanthus]

Originally posted by: Howard

Originally posted by: Acanthus

Originally posted by: Aharami

Originally posted by: James3shin
actually, what do you mean by "tighter bass"? Are you looking for more isolated thumps?

yes

adjust the EQ

if that doesnt work

you need mids.

Maybe he just needs to reduce the gain on the sub amp.

That could be, im thinking the bass response on the sub is too high, so its getting washy instead of having "punch".

 

[James3shin]

the gain is a very good suggestion.

 

[glen]

There is a special tool which is made for the purpose of diagnosing the problem with the sound; it is called an RTA. It escapes me why folks won't use one.

 

[Aharami]

Originally posted by: glen
There is a special tool which is made for the purpose of diagnosing the problem with the sound; it is called an RTA. It escapes me why folks won't use one.

never heard of it until now. So where can I get one and how much does it cost? Im just getting into audio now so Im learning as I go along.

 

[Aharami]

Originally posted by: Howard

Originally posted by: Aharami

Originally posted by: spidey07
put some poly fill in the sub. That will help.

correct me if Im wrong, but doesnt polyfill "make the sub think" that the internal vol is actually bigger than it is?

the question really is what kind of enclosure produces tighter, more accurate base response? Does the base get more boomy as you increase the internal vol?

Adding stuffing is the equivalent of increasing enclosure volume, which reduces the Q of the box (Q of 0.5 = critically damped, Q of 0.7 = maximally flat response, anything higher leads to peakiness).

I'll put up some graphs in a bit.

EDIT: The "room gain" of the car will make the bass sound much louder and might be contributing to the boominess.

http://www.rootminus1.com/howard/pics/jl10w7sealed.gif

do you have any links that explain what all these terms mean? I can just google, but askign just in case you know...

 

[glen]

Originally posted by: Aharami

Originally posted by: glen
There is a special tool which is made for the purpose of diagnosing the problem with the sound; it is called an RTA. It escapes me why folks won't use one.

never heard of it until now. So where can I get one and how much does it cost? Im just getting into audio now so Im learning as I go along.

They are about $1,000
here is one for sale at Amazon:
http://www.amazon.com/exec/obidos/ASIN/...0/wwwgoodcheapd-20/103-7729036-4187023
I bought that exact model for $500 from a place that was going to use it for a movie prop, but never did.
Someone in your town has one and knows how to use it.
Any car audio store should have one and know how to use it.
If they don't refuse to do buisness with them.

 

[glen]

Howard, put in a volume equal to over 10 times the VAS of that driver and show us the graph.

 

[Aharami]

Originally posted by: arcas
1.3 cuft seems awfully large for a sealed 10" enclosure. Are you sure that wasn't the recommendation fora ported enclosure? I have a 10" Image Dynamics sub in a 0.55 cuft sealed enclosure.

link to sub specs
PDF link to owners manual <-- page 4 has recommended enclosure dimensions