For a tru SQ system should I shoot for .707 or something else?

[teamquakecelica 10+ year member]

I'll be using a JL 12w7

Pheonic Gold Xenon 600.1 to power it...

Going in my daily driver 2002 Celica in the hatch

I'm sure I'm gonna go sealed... should I shoot for the magic # or not worry about it? Is there another # Ineed to shoot for?

PLEASE don't tell me to change equipment...

I love my w7... and the Xenon is plenty of power for me...

Please help me out!

Ryan

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[Fast1one 10+ year member]

Its all personal preference. Some people like the flatness, others like the punchiness of a smaller box, others want the lowend of a bigger box.

Unless your competing, then i would go for what YOU want. Thats what matters in the end. Try playing with Win ISDs graphs it will give you a ball park figure, but not perfect.

Remember that cabin gain will help your lowend a good amount, sometimes as much as half an octave below your predicted F3. Hope this helps...

 

[samson 10+ year member]

I can't get technical with you (still confused on that system Q stuff) and I have a different sub but I went from .5 to 1.0 cu ft sealed (which is the range the manufacture gave) and it gives a very different sound. It hits the lows with much more authority but it's also much "boomier". Supossedly lowered the f3 from 53 to 42 hz. I'm sure defferent subs react different but it definately made an audible difference in my case. To me, the 1.0 sounds better with rock and rap. I'd probably prefer the .5 with acoustical, easy listening or classical.

Probably not the best info, but hey...I tried. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[teamquakecelica 10+ year member]

anyone else?

Warbleed?

Ryan

 

[helotaxi 5,000+ posts]

Because of the way that the cabin interacts with the sub and the enclosure you can get away with as high as .9 in the car and not see a huge difference in response compared to .707.

 

[Fi Car Audio 10+ year member]

I prefer lower qtc alignments sealed. But I have strong midbasses to back up the punch. Just sounds more natural to me. I normally recommend .8 or higher to most kids as they like the kick more than things being smooth...

Ryan... loooooong time no talk //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Thanks...

Scott

 

[bass_lover1 10+ year member]

I'll be using a JL 12w7Pheonic Gold Xenon 600.1 to power it...

Going in my daily driver 2002 Celica in the hatch

I'm sure I'm gonna go sealed... should I shoot for the magic # or not worry about it? Is there another # Ineed to shoot for?

PLEASE don't tell me to change equipment...

I love my w7... and the Xenon is plenty of power for me...

Please help me out!

Ryan

It depends on your tastes. While a qtc of .707 will give you the flattest response, many people don't care for that sound. Going w/ a bigger box (lower qtc) will give you a bit more low end, but going to big will give you an overbearing boomy sound. Higher qtc (smaller box) will give you a punchier sound, but again too small and you severely lack any low end. It's all really a game of give and take, and what you're looking for. I agree with Scott though, I'll usually make the box slightly bigger for a lower qtc, but my front stage can easily keep up with it so it's not an issue for me there.

 

[teamquakecelica 10+ year member]

It depends on your tastes. While a qtc of .707 will give you the flattest response, many people don't care for that sound. Going w/ a bigger box (lower qtc) will give you a bit more low end, but going to big will give you an overbearing boomy sound. Higher qtc (smaller box) will give you a punchier sound, but again too small and you severely lack any low end. It's all really a game of give and take, and what you're looking for. I agree with Scott though, I'll usually make the box slightly bigger for a lower qtc, but my front stage can easily keep up with it so it's not an issue for me there.

I appreciate the help... I was trying to save some space by going sealed... but looks like I'll be in the 2cuft range to get a lower than .707QTC...

I'm pretty sure my CDT's have enough midbass to compensate.. so I'll prob go that route.. thanks for your imput... anyone else?

Ryan

 

[bass_lover1 10+ year member]

What are you using to figure out the qtc...I used to know the equation but it's been years since I've done box designing so I want to see where you're getting your numbers at, just to double check ya //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[teamquakecelica 10+ year member]

I was plugging the TSP's off JL's website into WIN ISD.. and it was giving me the QTC.. I figure its pretty accurate.. 1.65 yields a .750, 2cuft yields a .700, 2.25cuft yields a .690

Do yoou think thats right?... sounds kinda big but...

Ryan

 

[Immacomputer 10+ year member]

It also really depends on the sub you're using. Some subs will be very bottom heavy with a .7 alignment while others will still remain very flat in car. For example, my av12 in a .7 sealed alignment was very smooth from 80-50hz but picked up some boom around 40-35hz. I enjoyed this sound but others might not. My JL w6AE clone did very well in a slightly lower Q and remained very flat in car from about 40-100hz. It kept a good amount of punch to it and blended very well with my front stage. Any higher Q with that sub and I would have lost a good chunk of low end.

Oh, and both of these subs were in the same size enclosure and in the same vehicle with the same placement.

 

[bass_lover1 10+ year member]

I was plugging the TSP's off JL's website into WIN ISD.. and it was giving me the QTC.. I figure its pretty accurate.. 1.65 yields a .750, 2cuft yields a .700, 2.25cuft yields a .690
Do yoou think thats right?... sounds kinda big but...

Ryan

I don't remember exactly, I'll look into it when I get home (i'm on campus right now).

Also, what Immacomputer mentioned, while you may see a qtc of .707 from WinISD, your cars cabin gain will change that.

I'd personally design the box to give you the response YOU want to hear, .707 isn't always desired, I've tried it a few times, and for me it was a bit to neutral, but thats my tastes, you may like that.

 

[Immacomputer 10+ year member]

Well, your cabin gain won't change the alignment of the sub in the enclosure but it will boost the lower octaves of it giving a different frequency response.

 

[PatFitz9 10+ year member]

from what i have heard/used w7's like a big box. part of the reason i got rid of mine. not questioning you, but any reason you don't want more power? i loved my 12w7 with 1k watts and i would have given it more power if i had the amp for that.

 

[teamquakecelica 10+ year member]

from what i have heard/used w7's like a big box. part of the reason i got rid of mine. not questioning you, but any reason you don't want more power? i loved my 12w7 with 1k watts and i would have given it more power if i had the amp for that.

No Prob:suave:

I Have a stock alt. and an SVR up front... my lights dim a tad with that.. I'm not adding xtra batteries or anything of the sort.. I'm out of that stage.. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif I just want nice smooth bass to compliment my CDT 6.5" CF ES... Something that has good transients and blends well...

FYI Birthsheet on my xenon was 811w RMS //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Ryan