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Discussion Starter #1
I'm sure alot of people are leary of using passives in a vehicle, but I'm trying to implement an augmented widebander install in a Cherokee. Its a play/work vehicle so I don't want to to spend alot of dough on minidsp and 5/6ch amps. I own a pioneer 4/3/2 amp that is going to send a L/R signal to the front stage and a bridged to the subs (2 JL 8w0).

I plan to use the cheap tymphanys http://www.parts-express.com/pe/show...number=299-249 HP'd @300-400 with cheap caps and a bypass caps, in a location that is easily accessed if I need to swap the cheapo.

along with these pyramids http://www.parts-express.com/pe/show...number=290-025 . The reason Im chosing these is to try and get as low as possible up front and these model well in an extremely small enclosure (2 liters) however they are too sensitive @ 96db (One reviewer tested it to be 94db). Well I plan to use a 8db shelving low pass from 40hz to 100hz to make it totally flat in its range (50hz to 400hz) and equally efficient as the 2".

My questions are:

1) Is this even feasible?
2) I need a low pass on the woofer @ 400hz, could I make another shelf to drop it 18/24db? (I dont want to spend bucks on an inductor)
3) How will this all work if Im using the amps HP filter @ 50hz?
 

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how do you know it will be "totally" flat once you put it in the vehicle? a simple 12dB/oct filter will work just as well. unless you are giving them low power, I dont think 40hz will work well though. are you installing subs?(are these the subs?)
 

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Discussion Starter #3
You're right not totally flat, more like reasonably flat, before cabin gain. I want to cross at 12db @ 50hz, so with cabin gain it should work decently?

I'm using 2 JL 8w0 in the rear of the suv, these pyramids are going in 2 liter fiberglassed pods in the doors.
 

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You're right not totally flat, more like reasonably flat, before cabin gain. I want to cross at 12db @ 50hz, so with cabin gain it should work decently?

I'm using 2 JL 8w0 in the rear of the suv, these pyramids are going in 2 liter fiberglassed pods in the doors.
Forum members don't let forum members buy the pyramids
 

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You're right not totally flat, more like reasonably flat, before cabin gain. I want to cross at 12db @ 50hz, so with cabin gain it should work decently?

I'm using 2 JL 8w0 in the rear of the suv, these pyramids are going in 2 liter fiberglassed pods in the doors.
would need to know how much power you are gonna hit these with. pryamid are not know for high quality or smooth sonics, lol. but if you are around 100 watts it should be ok. if not, just raise the HP.
 

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Discussion Starter #6
I know, pyramids, yecck. I have super limited space for magnets and these are small, model well, and are cheap ($9). I only plan on giving 30 watts to the front stage, so they shouldnt see enough to blow up. I'm sure they have terrible fr above 500hz, so I want a steep XO.
 

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Discussion Starter #7
Also I'm curious how the filters I put on the speakers will work in conjuction with the HP the amp is providing. For example, the signal is cut 12db @ 50hz at the amp, with a 50uf cap on the widebander for 6db HP @ 300-400ish.
 

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I know you said that you dont want to spend money on inductors, but since you are not giving them alot of power. even 18ga air core inductors would work. if you want a steep slope, make a 24dB LR filter.
 

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Also I'm curious how the filters I put on the speakers will work in conjuction with the HP the amp is providing. For example, the signal is cut 12db @ 50hz at the amp, with a 50uf cap on the widebander for 6db HP @ 300-400ish.
if you do some quick math. 400hz x-over @ 6 db/oct.

200 -6db
100 -12db
50 -18db
25 -24db

that is just with the cap, if you add the 12db/oct that the amplifier HP adds in, then 25 will be 36db down. I am more concerned with a 2" widebander trying to produce 100hz only 12db down. if that is what they recommend, then great, but that seem a little low to me for such a shallow slope. if it was 18-24dB slope, would be fine.
 

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Discussion Starter #10
I just checked it in winisd and it seems to be okay. Below xmax all the way.

I guess that answers that one, now I'm still curious if I could pair a low pass shelf and a high pass shelf on the same signal.
 

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I just checked it in winisd and it seems to be okay. Below xmax all the way.

I guess that answers that one, now I'm still curious if I could pair a low pass shelf and a high pass shelf on the same signal.
no reason you couldnt as long as you dont do one of the following two things.

1) LP and HP to same driver (bandstop) that cut out all freq. EX: LP 100hz and HP 1000hz.
2) if they are separate drivers, then make sure they have parallel paths. (EI: each driver's passive is connect to THAT driver, the amplifier just becomes the source to each passive/driver pair)


I ran a set of tweeters, 6.5", 6x9" and (2)12" sub all of one amplifier in hybrid 3 channel mode once. everything had its own passive.
 

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Discussion Starter #12
Oh I meant on the same driver. I guess it would be a bandpass shelving filter. Google here I come...
 

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Oh I meant on the same driver. I guess it would be a bandpass shelving filter. Google here I come...
yup, nothing fancy about a bandpass. just a HP and LP on the same bus
 

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Those Pyramid's sound good, from about 700 and down to 80. That was just hanging in a door.
 

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Discussion Starter #16
Those Pyramid's sound good, from about 700 and down to 80. That was just hanging in a door.
In comparison to your SLS 6.5? Did it seem like they were really 96db?
 

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They sound good compared to what?

please explain...thanks
They sound better then the Kicker midbase speakers, by far., and sound just as good as the peerless sds. The sls sound better then both, but I think the peerless sls is not as loud as either of the speakers mentioned earlier in this post.
 

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In comparison to your SLS 6.5? Did it seem like they were really 96db?
They are louder then the sls 6.5. The Pyrmiad plays like the Peerless SDS.
 

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Discussion Starter #19
Just had PE test the woofer with WT3. Listed specs were WAY off. I really didnt think it would be 8db off, and .5^3 off on vas. I'm so naive...

Well by the time I find the magical woofer, I will probably have a minidsp to model all the filters....
 
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