Wiring two speakers in parallel, off a premade crossover?

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Instead of an easy answer, I recommend you search the web for a crossover designer. Plug in some values and see what happens.

Remember, you are only messing up half the crossover. Think about what that will do if the woofer crossover point changes but the tweeter does not.
 
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I think you would end up with a low pass similar to a 1st order at 1/4 the frequency. Depending on the crossover and the driver impedance curve.

Chart below shows a 2nd order L/R low pass (purple) and the same values with 1/2 the load (blue). Very dependent on impedance, of course.
 

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these tweeters are so horrible?!?

and running one of the midwoofers full range just makes it worse! haha

Need to get some grill cloth for the MDF panel that's currently painted grey ;) trying to keep it looking stock, while making it annoyingly loud... still has to sound OK though...

Is there a reasonable webpage or program to calculate the crossover frequency based on the components? rather than the other way around?
 

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this split speaker setup was advertised as being 90dB 1w/1m... does anyone think they'd really be this high? :p

I might measure the specs sometime, just to decide what tweeter to use, and how much it'll need attenuating...

except, I want to run the two midwoofers in parallel... meaning if I use an 8ohm tweeter, and the midwoofers are truly 90dB 1w/1m (4ohm), then I'll need a 99dB @ 2.83 volt tweeter...

I think... :p
 
You have clearly got some fab skills, now we need to help you with what to fabricate.

A car speaker tends to be very efficient, so 90 does not sound unreasonable. Where on earth did you come up with a need for a 99 dB tweeter? If the mids put out about 90 dB, the the tweeter needs to put out about 90 dB. The exact level is part of tuning.

It is more than a little late now, but did you think to mock this up first, or just read how cool multiple speakers look and start cutting up your car? One midbass is way more than a car can handle, or actually, your ears.
 
a year ago a man showed me his car , and he had the same arrangement
of speakers on the door , so it must be popular .
Then he put a 3" in a strange external box , then tw at ear eight and a stw
up , up . The sub was in a strange shape box in the rear .
Near the sub there were these ...bricks very shiny and solid , to give plenty of power , also incorporating ( positioned on removable PCB ) some active crossovers .
:xeye:
I suggested him to USE the high pass filter at 80 Hz to those double mids .
He had also the crossover made ( by just following the tech papers provided
by speaker's manufacturer which included some suggested crossovers )
by someone professional who asked him a lot-
:xeye:
For 2Ω it had a lowish value of the coil:cool::D
 
Every calculator you'd ever want to use:

mh-audio.nl - Calculations

vac

I realised after asking that, (I'd planned to calculate the current crossover point, and filter the midbass drivers at the same frequency with the new crossover) that the inductors have no labels on them.. so I don't know their values anyway :p

I do have the WT3, so can always measure them... but I'm not that worried :p

Still though! if these midwoofers are 90dB 1w/1m 4ohm, and I wire two in parallel, is my 99dB 1w/1m, 8ohm tweeter the correct sensitivity?
 
I realised after asking that, (I'd planned to calculate the current crossover point, and filter the midbass drivers at the same frequency with the new crossover) that the inductors have no labels on them.. so I don't know their values anyway :p

I do have the WT3, so can always measure them... but I'm not that worried :p

Still though! if these midwoofers are 90dB 1w/1m 4ohm, and I wire two in parallel, is my 99dB 1w/1m, 8ohm tweeter the correct sensitivity?

If you put the midwoofers in parallel it will become a 2 Ohm load and if your amp can drive this, it will be ok. The result would be an equivalent 6dB additional sensitivity. The tweeter@99dB/W will still be 3 dB more sensitive. That means you have to put an 8 Ohm resistor in series with it in order to get a match, but when doing so you would have to calculate the Xover for a 16 Ohm tweeter.

vac
 
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