PA Crossover Questions

[Apendecto]

The drummer that I play with just got a rocking vintage PA (dual 15 cabs, huge power amp, etc.) Just recently he got some horns (cab type) off of craigslist and has no idea how to hook it all up.

 

I would think he'd need a crossover so he's not getting a bunch of garbage coming out the horns, but what do I know?

 

What do you need to set up a two way PA system? If a crossover is needed, any recommendations that won't break the bank?

 

Thanks.

 

Yo.

[Craig Vecchione]

dbx makes a good crossover.

 

http://www.zzounds.com/item--DBX234

[mike fitzwell]

A used DOD 834 won't break the bank.

[Apendecto]

I'll check them out. Thanks.

 

Yo.

[Robin]

An electronic X-over/processor will certainly clean things up.

 

I'd also cross over a bit higher than the horn specs allow.

[Apendecto]

 

An electronic X-over/processor will certainly clean things up. I'd also cross over a bit higher than the horn specs allow.

 

 

Good to know. These may be some homemade cabs. Would the specs be printed on them?

 

Yo.

[Thunderbroom]

 

dbx makes a good crossover. http://www.zzounds.com/item--DBX234

 

 

I'm pretty certain that's the one we have.

[Robin]

 

Good to know. These may be some homemade cabs. Would the specs be printed on them? Yo.

 

 

Homemade cabs? Probably not, nor on the drivers either.

 

As a general "rule," I don't like to cross 1" horns lower than about1.6k or

2" ers lower than 1.2k.

 

Of course, this is program dependent. With some folksy, ie. a "lighter" type fare, a lower X-over point will work just fine.

[Apendecto]

 

I'm pretty certain that's the one we have.

 

 

Have you had any problems with it?

 

Yo.

[Apendecto]

 

Homemade cabs? Probably not, nor on the drivers either. As a general "rule," I don't like to cross 1" horns lower than about1.6k or 2" ers lower than 1.2k. Of course, this is program dependent. With some folksy, ie. a "lighter" type fare, a lower X-over point will work just fine.

 

 

Good to know. I'm swimming in uncharted territory and the dude with the PA knows less than I do.

 

Yo.

[Kindness]

Homemade cabs? Probably not, nor on the drivers either. As a general "rule," I don't like to cross 1" horns lower than about1.6k or 2" ers lower than 1.2k. Of course, this is program dependent. With some folksy, ie. a "lighter" type fare, a lower X-over point will work just fine.

 

I don't like to cross 1" below about 6-8kHz with 10kHz being ideal.

[Apendecto]

I don't like to cross 1" below about 6-8kHz with 10kHz being ideal.

 

No {censored}. So horns are really only taking the high-highs.

 

Yo.

[Thunderbroom]

 

Have you had any problems with it? Yo.

 

 

None. We've been using it for a couple of years now.

[Kindness]

 

No {censored}. So horns are really only taking the high-highs. Yo.

 

 

Depends on the speaker design and my comment was a little off topic from what you were asking questions about. My main cabinets are crossed over from woofer to midrange at about 1kHz and from midrange to tweeter at about 10kHz. There is almost no signal coming through the tweeters when used as bass cabinets. I just designed another more high efficiency cabinet to use with my lower powered tube amps and I am using only a woofer and midrange. The crossover is at about 600 Hz and the midrange carries the signal up to about 6 Hz. I didn't even include a tweeter because I don't need any of the content above 4-6kHz. This is all totally separate from your issue, which is crossing over between two separate cabinets. Your dual 15 cabs are full range? If so, keep running them full range. I assume the horns have less low end extension. If so, you just need a high pass filter to send them a signal above a comfortable threshold. That might be 250 Hz, it might be 500 Hz, it might be 1 kHz. Without knowing the design specs, it is hard to have any idea what would work.

[Robin]

I don't like to cross 1" below about 6-8kHz with 10kHz being ideal.

 

I think he's talking about 2-way P.A. cabs.

 

15's to horns.

 

In my experience, the hi-mid efficiency drops off severely after around 1k in 15's.

[Kindness]

I think he's talking about 2-way P.A. cabs. 15's to horns. In my experience, the hi-mid efficiency drops off severely after around 1k in 15's.

 

Which is why I said my post is getting away from the topic at hand. I agree completely about your observation with 15's. I've never used on that I thought was worth crossing over any higher than 1 kHz.

 

I also am not exactly sure what the components are in the system that is being contemplated. It sounded to me like there were existing 15" full range PA cabs and recently they acquired "horns" that were going to be added as separate cabs to the system. I don't know what the "horns" are, I don't know what the 15's are, I don't know if either are full-range. I'm a little confused.

[Robin]

Which is why I said my post is getting away from the topic at hand...

 

My bad K.

 

*reminds self to read the post, Robin*

 

[Kindness]

My bad K. *reminds self to read the post, Robin*

 

Hahaha. I made the same mistake earlier today on another thread.

[Apendecto]

I'm in the dark as much as you guys since I don't have any specs. Hell, I didn't know there were such things as a horn in a a box.

 

When I know what I'm talking about, I'll come back.

 

Yo.

[georgestrings]

 

Have you had any problems with it? Yo.

 

 

 

I have one for my PA - it has been 100% trouble-free, and is head and shoulders above the DOD 835 it replaced...

 

 

 

- georgestrings

[Apendecto]

 

I have one for my PA - it has been 100% trouble-free, and is head and shoulders above the DOD 835 it replaced... - georgestrings

 

 

Good to know. Thanks.

 

Yo.

[Craig Vecchione]

Get the details of what it is you're buying...pictures may help too, of the components etc. There are guys over in live sound who can recognize drivers on sight and get basic settings.

[rpsands]

Hey, I've got a question about Crossovers I thought I'd toss in here.

 

Do they have electronic crossovers that accept powered inputs? e.g. like, the speaker out from a Pa's power amp -> crossover -> high/low

 

Most crossovers I've seen I got the impression that they need to be output back to a power amp (more accurately 2+ power amps) and then sent out to speakers from there.

 

Passive crossovers however accept the power amp output, which is nice (though I'm told you lose some fidelity or whatever).

 

Edit: Could you make a passive crossover box to split a signal fairly easily, with an input and two output jacks for example? (saying you had like, a 15" sub and a 12" woofer or something, with no internal crossovers)?

[Craig Vecchione]

 

Hey, I've got a question about Crossovers I thought I'd toss in here. Do they have electronic crossovers that accept powered inputs? e.g. like, the speaker out from a Pa's power amp -> crossover -> high/low Most crossovers I've seen I got the impression that they need to be output back to a power amp (more accurately 2+ power amps) and then sent out to speakers from there. Passive crossovers however accept the power amp output, which is nice (though I'm told you lose some fidelity or whatever). Edit: Could you make a passive crossover box to split a signal fairly easily, with an input and two output jacks for example? (saying you had like, a 15" sub and a 12" woofer or something, with no internal crossovers)?

 

 

Yes, they do exist. They're expensive, don't handle a lot of power, and are not nearly as effective as an active crossover.

[Apendecto]

 

Get the details of what it is you're buying...pictures may help too, of the components etc. There are guys over in live sound who can recognize drivers on sight and get basic settings.

 

 

I'll bring my camera to my next jam. Good idea.

 

Yo.