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View Full Version : how will extra spiders effect design?



plugger
01-22-2012, 02:46 PM
dont know if this is the right section or if it should be in subwoofers but here goes

single 15" audioque HDC3 box build, all i know about the sub is it was ordered with "extra" spiders
i will be pushing it with 1200-1500 watts rms. should i change the box audioque recommends for this sub to account for the extra spiders the sub was built with? any help appreciated

T.I.K.
01-22-2012, 02:53 PM
Subs with tighter suspensions tend to need larger boxes. You're not really pushing it with a ton of power, so I'm gonna go ahead and say your box is gonna have to be me huge.

kushy_dreams
01-22-2012, 05:17 PM
Subs with tighter suspensions tend to need larger boxes.

uhhh :eyebrow:

pretty sure its the opposite way around, tighter suspensions need less volume, there are still other parameters like qts that must be considered as well.

ahole-ic
01-22-2012, 05:20 PM
uhhh :eyebrow:

pretty sure its the opposite way around, tighter suspensions need less volume.

Wrong. Tighter suspensions need much larger enclosures. They inherently have a higher fs. More spiders should only be used if the woofer is bottoming out. The looser the suspension can be without mechanically reaching it's limits while maintaining linearity will yield the highest efficiency and extend to the lowest frequencies.

kushy_dreams
01-22-2012, 05:23 PM
qts is still important thought because you dont need as big of a box as the qts gets lower.

CAT MAN
01-22-2012, 05:25 PM
Wrong. Tighter suspensions need much larger enclosures. They inherently have a higher fs. More spiders should only be used if the woofer is bottoming out. The looser the suspension can be without mechanically reaching it's limits while maintaining linearity will yield the highest efficiency and extend to the lowest frequencies.
and bingo was his name-o

ciaonzo
01-22-2012, 05:41 PM
Wrong. Tighter suspensions need much larger enclosures. They inherently have a higher fs. More spiders should only be used if the woofer is bottoming out. The looser the suspension can be without mechanically reaching it's limits while maintaining linearity will yield the highest efficiency and extend to the lowest frequencies.Tighter suspension with high motor force will yield a low Q and a small Vas. Both equal a small enclosure.

97maxima
01-22-2012, 05:53 PM
Tighter suspension with high motor force will yield a low Q and a small Vas. Both equal a small enclosure.

I think your mistaken there

ciaonzo
01-22-2012, 05:55 PM
I think your mistaken thereThis is your chance to prove me wrong.

97maxima
01-22-2012, 05:57 PM
So for example a mt with 5 spiders will shine in a small box, say 5 cubes. that would not be a very efficient setup.

ciaonzo
01-22-2012, 06:02 PM
Your example of a small box for an unknown size of driver is not realistic.

Simply put, high Vas figures equal a large enclosure. I'm not talking about efficiency or any other factor. High Vas figures come from soft, highly compliant spiders. Not multiple stiff spiders.

ahole-ic
01-22-2012, 06:08 PM
Tighter suspension with high motor force will yield a low Q and a small Vas. Both equal a small enclosure.

So your contention is that fs doesn't matter at all?

97maxima
01-22-2012, 06:09 PM
sorry meant to say an mt 18. The original question was "should i change the box audioque recommends for this sub to account for the extra spiders the sub was built with? "
So on the same power in the same enclosure same subs more spiders he might has a lose in score. unless he increased box size or power.
You said a tighter suspension with high motor force equals a small enclosure correct? Kinda opposite of the truth in this case. HDC-3 motors are not super strong but if you keep putting spiders on them your small box will become a less efficient setup

ciaonzo
01-22-2012, 06:14 PM
So your contention is that fs doesn't matter at all?That's a bit presumptuous. I think we should agree on a criteria before we really go back and forth. My focus is solely on root question - how will extra spiders have an effect? My root answer was that extra spiders will drive down the Vas figure. Yes, Fs will go up as well.

Qts will matter more than Fs when it comes to high Vas figures.

ciaonzo
01-22-2012, 06:17 PM
sorry meant to say an mt 18. The original question was "should i change the box audioque recommends for this sub to account for the extra spiders the sub was built with? "
So on the same power in the same enclosure same subs more spiders he might has a lose in score. unless he increased box size or power.
You said a tighter suspension with high motor force equals a small enclosure correct? Kinda opposite of the truth in this case. HDC-3 motors are not super strong but if you keep putting spiders on them your small box will become a less efficient setupI see the logic you are using and you're correct from the efficiency standpoint. I'm not trying to be a ********, don't take it that way. I was more interested in addressing the statement that eCrack made concerning tighter suspensions need larger enclosures as an absolute.

ahole-ic
01-22-2012, 06:20 PM
I don't want to go back and forth. I feel like I have a pretty reasonable understanding but I don't know it all. I respect your opinions.

ciaonzo
01-22-2012, 06:24 PM
I don't want to go back and forth. I feel like I have a pretty reasonable understanding but I don't know it all. I respect your opinions.As I do yours. I didn't mean back and forth as a pissing contest, just something for others to learn from. And for me, too. There are design considerations that you 'loud' guys take into effect that I do not, so I get to understand that point of view more from discussions like these.

ciaonzo
01-22-2012, 06:42 PM
So others can see where my argument is derived from...

Plug this formula for a simple sealed enclosure. Vas is in liters and remember, a larger number indicates a softer suspension. Change the Vas number and see how Vb (box volume) is affected.

Vb = Vas / (( Qtc / Qts ) - 1)


Also, this is from a set of T/S definitions.

VasMeasured in litres (http://en.wikipedia.org/wiki/Litre) (L) or cubic metres, is a measure of the 'stiffness' of the suspension with the driver mounted in free air. It represents the volume of air that has the same stiffness as the driver's suspension when acted on by a piston of the same area (Sd) as the cone. Larger values mean lower stiffness, and require larger enclosures. Vas varies with the square of the diameter. A typical factory tolerance for Vas spec is 20–30%.

plugger
01-22-2012, 07:09 PM
ok all im really looking for is if i should make my box a little bigger or a little smaller than the 4.5 cubes... all i have got from this so far is that my sub isnt going to be as efficient as it could be because it has the extra spiders

plugger
01-22-2012, 07:12 PM
keep in mind ill only be giving it 1200 - 1500 watts, should i tune it higher than 36hz?

Bettr n' Revrse
01-22-2012, 07:14 PM
Hell OP it's just an AQ build one to specs and play it...

plugger
01-22-2012, 07:25 PM
Hell OP it's just an AQ build one to specs and play it...

wasnt the answer i was looking for, but unless anyone else suggests sometnin thats what ill have to do. anyone else have tuning recommendation or box size?

Bettr n' Revrse
01-22-2012, 08:56 PM
wasnt the answer i was looking for, but unless anyone else suggests sometnin thats what ill have to do. anyone else have tuning recommendation or box size?

Id go a little lower...

pro-rabbit
01-22-2012, 10:10 PM
I spoke with OP via PM.

He was a victim of a less then truthful seller. It is a stock AQ HDC sub.

So no worries.

CHEMMINS
01-22-2012, 10:31 PM
fs 35.66 hz
qms 4.74
vas 1.54 ft^3
mms 468.3g
revc 2 ohms in series
qes .36
spl 89.2 db 1w1m
qts .34
le 2.81 mh
bl 25.33

As you can see....these T/S specs make for a small box. If you had to venture a guess as to what size sub this is, what do you figure? This will add to the spiders/efficiency/fs debate.

TheUnderFighter
01-23-2012, 01:44 AM
I spoke with OP via PM.

He was a victim of a less then truthful seller. It is a stock AQ HDC sub.

So no worries.

So.... can we get the name of the dishonest seller so future buyers could beware? This question is more directed towards OP, just using your post as a reference Dustin.

Bettr n' Revrse
01-23-2012, 01:53 AM
So.... can we get the name of the dishonest seller so future buyers could beware? This question is more directed towards OP, just using your post as a reference Dustin.

Good question

plugger
01-23-2012, 02:05 AM
Good question

well im not tryin to step on his toes, but it was a local guy in marion, iowa, his names matt. hes on midwestspl.com alot as firefox, it was a good deal on the sub, but he did say to me that he paid extra for custom work (extra spiders added). thanks for the help

jolly_26
01-23-2012, 03:24 AM
fs 35.66 hz
qms 4.74
vas 1.54 ft^3
mms 468.3g
revc 2 ohms in series
qes .36
spl 89.2 db 1w1m
qts .34
le 2.81 mh
bl 25.33

As you can see....these T/S specs make for a small box. If you had to venture a guess as to what size sub this is, what do you figure? This will add to the spiders/efficiency/fs debate.


Would have guessed 10", lower end sub. But since you're making a point, and the logical answer will be wrong, some kind of custom 15"?

Louisiana_CRX
01-23-2012, 03:52 AM
http://i100.photobucket.com/albums/m24/Louisiana_CRX/Brown_Recluse_.jpg

TheUnderFighter
01-23-2012, 04:09 AM
well im not tryin to step on his toes, but it was a local guy in marion, iowa, his names matt. hes on midwestspl.com alot as firefox, it was a good deal on the sub, but he did say to me that he paid extra for custom work (extra spiders added). thanks for the help

Thanks man, it's just good to know. Maybe he had bought it from someone else that lied to him. But it's just good to know so people can keep an eye out in the future.

Bettr n' Revrse
01-23-2012, 04:26 AM
Nice little sum *****

pro-rabbit
01-23-2012, 12:57 PM
well im not tryin to step on his toes, but it was a local guy in marion, iowa, his names matt. hes on midwestspl.com alot as firefox, it was a good deal on the sub, but he did say to me that he paid extra for custom work (extra spiders added). thanks for the help

Which AQ never has done. There were a few exceptions but as I told you the one you have is not one of those exceptions.

As for the new people answering the phone at AQ saying they will make custom subs. They are wrong still. They are employed by DD but doing extra work by helping on the AQ side. AQ is an "out of the box" company which means NO CUSTOM builds.(with minor exceptions)

plugger
01-23-2012, 01:03 PM
cool thanks for that info that really helps, I wonder why the guy said i should put it in a 6 cubic foot box though?

pro-rabbit
01-23-2012, 01:05 PM
cool thanks for that info that really helps, I wonder why the guy said i should put it in a 6 cubic foot box though?

Was it Kevin?

plugger
01-23-2012, 03:17 PM
yes

sacsking916
01-23-2012, 03:22 PM
yes

he's a noob :suicide: jk i dont know the guy. but rabbit should know more about AQs setup than most others

pro-rabbit
01-23-2012, 03:24 PM
he's a noob :suicide: jk i dont know the guy. but rabbit should know more about AQs setup than most others

Kevin is over customer service for DD. He helps AQ when possible. (all though positions may have changed do to the recent happenings at AQ/DD)

He is a great guy and been in the industry for a long time, but some things like enclosure specs are not his strong area.

On a side note, that guy can run forever... literally he really can.

sundownz
01-23-2012, 03:26 PM
On paper in a box model program a tight suspension DOES call for a smaller box -- box model programs shoot for the flattest response or a 0.707 Qtc in a sealed box typically.

What we know in real life is that we don't necessarily always care about the flattest response -- in which case a stiffer spider woofer is more difficult to move in the small box we want for a flat response. So we sacrifice and use a bigger box to allow it to get moving and get a saddle shape response -- which almost always is the case with tight "SPL" type woofers.

On the other end... a driver with loose suspension will have a high Qtc and a response bump in smalled sealed and also a big hump in response in a smaller ported box. So still not flat... but may be desirable to increase it's mechanical power handling.

In short... both sides can be right depending on what you want.