Building PA. Need Help with Crossover.

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Hello,

I'm building a PA for my band to save a little money and to get a better band for our money. Where I'm stumped is the cross over and wiring Speakon jacks. I haven't bought anything yet, but here are the plans.

I will build the cab myself, which I have some experience doing. I've built my own car audio cabs and recently a 5E3 guitar amp.

The mains will be a 2 way design. Here are the drivers I plan to use.

Selenium D220Ti 1" Titanium Horn Driver 8 Ohm 1-3/8"-18

Dayton Audio PA380-8 15" Pro Woofer


Here is a cross over that might work? I'm not sure what to use for a crossover.

Dayton Audio XO2W-2K 2-Way Crossover 2,000 Hz

The PA will be for small to medium (100-150 people) venues. Also, what about attenuating the 1" driver incase it is too loud? Any help would be appreciated.
 
I my opinion trying to cross over a 15" to a 1" compression driver is not going to work very well. The 2 drivers are not going to sound very good at the crossover point.
As you intend to use subs as well I would look at a 12" mid or even a 10" -
My 10" mids reach above 3Khz.
The other option is to use a bigger 1.5" or 2" HF driver, but this usually gets expensive!
As for HF attenuation try 'L pad attenuator' in your favourite search engine.:)
 
The Selenium unit is quite popular so I would take the route Xoc1 is suggesting and think about a 10". The attenuation can be done with fixed resistors or a variable L-pad if you think you might need to adjust it for each venue. The XO you might want help with as the off the shelf kind are not usually very satisfactory as the drivers themselves determine the components to be used rather than just putting together the components for a known impedance as they are offering in the one you link to.
 
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As you intend to use subs as well I would look at a 12" mid or even a 10" -

sorry, but I don't see any mention of subs :confused:

anyway, whether a 15" could work for a 2way, would very much depend on the actual woofer
but it might have the advantage of greater powerhandling sensitivity

whether the Dayton is a semipro subwoofer or a midwoofer is hard to say
but the relatively short Xmax and low Qts could indicate a high sensitivity midwoofer

the important figure is mms(moving mass)

if used for vocal only, then maybe a 12" will do
and two of them would be even better
 
Don't do it if you can possibly help it! Even for small PA, don't ever even start using passive crossovers. There are many reasons not to, like they waste too much power, make each amp run full-bandwidth which adds to IM distortion, can hurt the damping factor the driver sees, changes the load the amp sees, require complex zobels, don't behave the same as power levels change, etc. etc.. There are excellent affordable active crossovers from Peavey and Behringer etc. and the money you spend on an active crossover will be saved on power amps, especially as your PA grows later; and you might get features like delay etc too. Pay attention to whether the amps and active crossovers have balanced low-impedance inputs for when you grow to add longer snakes to the board. Even monitors should have active crossovers. Think of each of your speaker boxes as a component, and eventually you can combine them differently for each venue.

At the really cheap end, I have a used JBL stereo crossover with 500 hz plug-in cards which I'll sell you for less money than 2 good crossovers would cost you. It's not balanced in or out, but it's cheap. If you wanted to go 3-way you could still use passive x-over between the mids and highs, but drive the subs directly from the active crossover. You can make your own active crossover for pennies, or get power amps with slots for crossover filters, or build crossover circuits into your amps. I see used Peavey active crossovers on eBay for as little as $45 USD.

I don't even use passive crossovers at home, except for in one bedroom and the bathroom system. They cost MORE than active, when you include the cost of power amps.
 
And the feature I like most, an active crossover allows you to easily put a limiter on the section where feedback would most likely occur. You can protect sensitive ears and drivers without limiting other bands. Nothing ruins a show quicker than making everyoune deaf with a feedback squeal except subsequent loss of highs, a danger that becomes more possible as your system grows. But with an active crossover, you can put limiters on each output section, to protect ears and equipment, and you can adjust that limit on-the-fly. You can make sure the feedback will never be painful, never be louder than the music's peaks so feedback is barel noticed except by you. Sure beats the way fuses can ruin a speaker's performance. Eventually you may want to EQ each speaker section post-crossover. There's lots moe reasons too...like putting automatic feedback destroyers post-crossover, etc.
 
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