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Napoleon of DIYMA
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Discussion Starter · #1 ·
Ok here's some data to put you in context

I am driving a Dodge Caravan 2002 and i enjoy listing to vocal jazz, trio jazz, blues, rock and some psy/goa trance...

Hardware:
source: Alpine DVA-9861 with PXA-H701 (ai-net & fiber)

tweeter: CDT DRT-26T (in A-Pillar off-axis)
midrange: CDT ES-4 (stock 5 1/4 dash location,bquiet done)
midbass: CDT ES-06 (stock 6x9 door location,bquiet done)
subs: 2x SSA ICON 12D1 (in 4cu.ft @34Hz)

amp1 (t & m): Arc Audio KS300.4
amp2 (mb): Arc Audio KS300.2
amp3 (sw): Sundown SAZ-1500D

To my taste the system sound good, but under 100Hz it's another story. As you can see in terms of subs i have lots of output... well to much

and to blend this with my midbass it's kind of hard.

I am looking for SQ but with a twist of :eek: on the subbass side. I was thinking sealed for the subs to flatten the response and upgrade the MB to a 8 so i can lower the xover of the subs even more (currently @63).

What do you think?
 

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Running your subs sealed will reduce some of the boomyness and give you a more controlled bass reproduction. Im running two 13kv.2's in a 1.2cu (i think) enclosure now and I get a good balance of sq and chest bump on certain notes.

I cant wait to put my 7kv.2s in for front midbass so I can pull my subs outta the 125hz range. Maybe try crossing the mb's a little higher and your subs a little lower?
 

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Napoleon of DIYMA
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Discussion Starter · #3 ·
subs @125Hz and i'm the one complaining...;)

SSA recommend a 1.5cu.ft (1.35 + 0.16 displacement) per sub, should I go with that or try smaller?

So you want me to try to lower the LPF on the subs to 40Hz and up the HPF on the MB to 80Hz?

what happen between 40 and 80, the cabin gain will compensate?

Thanks
 

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subs @125Hz and i'm the one complaining...;)
lol yeah tell me about it.

im a little confused, what are your current settings?

I meant if you set the hfp for the mid bass a little higher so it doesnt play as low and the lfp on the sub so it doesnt play as high. still have them meet so that each set of drivers has their own frequency and you dont miss any. I mean if the sub plays low enough affectively it should be able to fill in the lower notes. If your listening to jazz your kicks should be punchy and the bass should be smooth and a little tame(well depending on the song of course). With a stronger emphasis on vocals horns and pianos from the 200hz to 8khz range with just a little sizzle uptop. I havent mixed a jazz track in forever though so i could be wrong.

Im not too familiar with box design, I usually just have them stick to the manufactures specs. But experimenting is never bad.
 

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Napoleon of DIYMA
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Discussion Starter · #5 ·
Currently the LP is set @ 63 (-24) for the subs and the HP set @ 63 (-6) for the MB.

My cabin gain peak at around 55Hz and i want the sub to play under that. Then get a MB driver that will be able to play low enough to get to the sub, let's say I want them to meet @ 45Hz. Right now the ES-06 can't handle this low at moderate-high volume.
 

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Napoleon of DIYMA
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Discussion Starter · #7 ·
Get a midbass speaker or two on each side and you'll be all set ;)
I am open to suggestion ;-) if the CDT doesn't qualify as midbass what will?
 

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Personally I would either:

A.) change the crossover point on the subs to a higher value and EQ some of the low end out so it sounds balanced. I don't know why people are so scared to crossover their sub high, but it should stop. You have so much cone area for midbass in the rear, try using it for a change. (unless your subs just sound horrible) Start by raising the midbass crossover until the front midbass can handle anything you throw at them. Then blend the sub in, playing with crossover points, slopes, and T/A until you can't locate it.

B.) Move to a sealed box and move the crossover point higher as noted above. EQ shouldn't be needed.
 

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Napoleon of DIYMA
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Discussion Starter · #10 ·
Personally I would either:

A.) change the crossover point on the subs to a higher value and EQ some of the low end out so it sounds balanced. I don't know why people are so scared to crossover their sub high, but it should stop. You have so much cone area for midbass in the rear, try using it for a change. (unless your subs just sound horrible) Start by raising the midbass crossover until the front midbass can handle anything you throw at them. Then blend the sub in, playing with crossover points, slopes, and T/A until you can't locate it.

B.) Move to a sealed box and move the crossover point higher as noted above. EQ shouldn't be needed.
Hey thanks, ill try "A" after work...

Now i am going to do a search on CDT and try to find out why there's no love for them...
 

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I also believe you are moving the crossover in the wrong direction. Let those subs play higher and make it so they actually blend with the mids.

I'm on the side of the fence that believes super low crossed subs is ridiculous. Localization doesn't happen until above 100hz. The key to good midbass and upfront sub bass is to have the mids and sub blend well. It's very difficult to do this when you are trying to make your mids play down to 60hz and your sub is really loud from there down.

Like fast1 said, raise the midbass point to about 100-120, find a good point where they can still play with authority. Then raise the sub to blend. Letting the sub play those frequencies will take some of the pressure off of the mids and there will still be plenty of information from the front speakers to give the illusion of up front subbass.
 

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lol there you go .... thats what i was trying to say. I personally dont like my subs up that high they sound pretty good @ 80hz. the cdts should play well down there.
 

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I also believe you are moving the crossover in the wrong direction. Let those subs play higher and make it so they actually blend with the mids.

I'm on the side of the fence that believes super low crossed subs is ridiculous. Localization doesn't happen until above 100hz. The key to good midbass and upfront sub bass is to have the mids and sub blend well. It's very difficult to do this when you are trying to make your mids play down to 60hz and your sub is really loud from there down.

Like fast1 said, raise the midbass point to about 100-120, find a good point where they can still play with authority. Then raise the sub to blend. Letting the sub play those frequencies will take some of the pressure off of the mids and there will still be plenty of information from the front speakers to give the illusion of up front subbass.
I have had success crossing over as high as 150hz if you can believe it. I think the only reason I could locate it was because of a buzzing that pulled my attention to the rear. And the fact that the subs were in the trunk, so I am sure it wasn't very flat above 100hz. Amazing what careful selection of crossover points, slopes, and T/A could do.

Anyone else who sat in my car could not tell that the sub was in the rear at all. They kept staring at my mids scratching their heads :laugh:
 

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I have had success crossing over as high as 150hz if you can believe it. I think the only reason I could locate it was because of a buzzing that pulled my attention to the rear. And the fact that the subs were in the trunk, so I am sure it wasn't very flat above 100hz. Amazing what careful selection of crossover points, slopes, and T/A could do.

Anyone else who sat in my car could not tell that the sub was in the rear at all. They kept staring at my mids scratching their heads :laugh:
I hear you man, I have had mine up to 120-125hz (whatever it is on the 880) and I didn't have any localization. My permanent setting is 100hz. Like you said, at those frequencies it's usually the resonating panels that actually cause the localization.

Take care of the buzzes and rattles and play your sub up high, blend it with the mids and enjoy good midbass.
 

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Napoleon of DIYMA
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Discussion Starter · #15 ·
ok did some testing at 100Hz for both

3 problems

Now I experience some delay in the kick
I am asking more power from my sundown so the light are dimming...
Like others said the localization is due to rattle...I have a Caravan what should I expect!

Other than that, you are right it it sound tight as hell.

So the delay could be fixed using the T/A, sealed box, and box location i guess?
 

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ok did some testing at 100Hz for both

3 problems

Now I experience some delay in the kick
I am asking more power from my sundown so the light are dimming...
Like others said the localization is due to rattle...I have a Caravan what should I expect!

Other than that, you are right it it sound tight as hell.

So the delay could be fixed using the T/A, sealed box, and box location i guess?
T/A will help, but more importantly you should play with slopes and levels as well since they introduce a phase shift around the crossover point. 6db is 90 degrees, 12db is 180 degrees, 18db is 270, and 24db is 360 degrees or NO NET phase shift. I usually start with 24db and work my way down if I need to with the sub or mids.

The mids will also have a phase shift depending on the enclosure alignment. Thats why 24db may not always work. The goal is to have a seamless transition, completely flat through the crossover region. If there is a gap or a bump then the illusion of one speaker playing bass and midbass will fall apart. This goes for your midrange and tweeters as well. You want it to sound as one point source, not multiple speakers (referred to as lobing).

You don't need a sealed box. I was just suggesting that to remove a bloated low end, should you experience that.

As far as Box location, the way you AIM the sub may help with the rattles and the upper frequency response, so its a good thing to try. The rattles are something you will NEED to fix. Takes time, but its well worth it because it becomes that much harder to localize your sub, if at all (which should be your goal).
 

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Napoleon of DIYMA
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Discussion Starter · #17 ·
wow thanks, great info

I put back my subs to there normal position (completely in the back, sub up) and the delay is already less (they were in the middle of the van facing the hatch). Ill play with the phase and TA over the weekend.

Thanks again
 

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wow thanks, great info

I put back my subs to there normal position (completely in the back, sub up) and the delay is already less (they were in the middle of the van facing the hatch). Ill play with the phase and TA over the weekend.

Thanks again
Your welcome! Have fun and report back :)
 

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Napoleon of DIYMA
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Discussion Starter · #19 ·
Ok so after a week I really like the new setting for rock,techno and even blues, but for jazz it's still better when my subs have a LP @ 63 instead of 100. I can live with 2 preset on the PXA...

Also the T/A did fix the delay problem (20ms)

It's unbelievably tight&loud now
Thanks :thumbsup:
 

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Ok so after a week I really like the new setting for rock,techno and even blues, but for jazz it's still better when my subs have a LP @ 63 instead of 100. I can live with 2 preset on the PXA...

Also the T/A did fix the delay problem (20ms)

It's unbelievably tight&loud now
Thanks :thumbsup:
:):):):):):):):):)
 
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