Passive speakers

Possible, yes -- advisable, no.

Powered speakers have DSP's/crossovers/EQ's built into the amplifier panel. If you bypass that altogether, you're driving the speakers with raw signal. They will likely sound far worse than they come from the factory, and the built-in protections that reduce LF from going to HF drivers and vise versa will be gone, making it likely you will damage the speaker elements -- if not immediately then over time.
 
The quick answer is: NO.

The more measured answer is "maybe, if you have an amplifier, DSP crossover, and access to the crossover filter data from the manufacturer. What you'll not have is protection and limiting.

Return the amp module for service or order one as a replacement part.
 
A second on the "maybe." If it is a two-way system (horn and speaker) you will need a crossover network to separate the highs and lows. Of course, some powered speakers only contain a single amplifier and already contain a passive crossover. Most better speakers will have separate amplifiers for the highs and lows. Unless you install a passive crossover, you will blow the HF driver.
Also as mentioned above, the active amplifier may also contain built in equalization to compensate for the response curve of the speakers they chose. Without that EQ, they may sound pretty bad.
 
A second on the "maybe." If it is a two-way system (horn and speaker) you will need a crossover network to separate the highs and lows. Of course, some powered speakers only contain a single amplifier and already contain a passive crossover. Most better speakers will have separate amplifiers for the highs and lows. Unless you install a passive crossover, you will blow the HF driver.
Also as mentioned above, the active amplifier may also contain built in equalization to compensate for the response curve of the speakers they chose. Without that EQ, they may sound pretty bad.
so in a bind, without access to spares or fast shipping, you can experiment after taking the thing apart, inspecting to see if the crossover is passive post-amp, or was done with bi-amplification in their amp module. now you know what you need to replicate.

1. If 1 amp ran it all - you're probably ok, but run pink noise at reasonable level (careful) and use the best flattest mic you have and the RTA on your board or an outboard gizmo to see how the frankensteined cabinet responds. Fix up the response in software if you need to.

2. If it was bi-amped, or tri-amped ... try to look up what the crossovers were. Or by lifting speaker wires carefully on your remaining still-working unit, you can measure to determine Xover freqs and slope. Then replicate in software upstream of the substitute amps.

Or - tear your hair out, hustle out to a rental house or see if the mfr can fedex you a replacement.

One thing I've learned the hard way - when the amp module goes, often it can take the drivers with it. Don't assume they are still ok til you test them and listen carefully.

Had a facility with bad flaky power problems not long ago that was burning out stuff, wiping memory in devices, etc. fairly regularly. The last pass thru there somehow got DC to come out of an old QSC amp and totally fried the woofers in big old EV 15" 2 way cabinets. Sort of awesome failure mode, in an awful way for this YMCA.
 
I'll be honest... I do it all the time. As a TD for a small community theater, if it doesn't involve soldering irons and gaff tape, it's not going to happen.

I have two subs right now. One is a Yorkville 10" with a fried amp, so I bypassed it and feed it 300w with a low pass set at about 80hz. The other one is a super-craptastic home-built particle board bandpass box from the trunk of some kid's civic with two Kicker 12" subs that I feed with about 400w in series to keep a safe impedance. Super hacked, but it sounds pretty incredible. I did have to glue the surround on one speaker. The bandpass of the box lets the excursion go a little wild around 60hz. I keep that second one far out of sight lines by putting it under the seating risers. A nice clap of thunder really wakes up the sleeping people, but they don't have to see how hideously ugly it is.

I would suggest just doing the research on crossover points that the boxes/drivers were designed to handle, then bi-amp it or fab up your own crossovers. Online plans are a google away, and parts express has crossover kits you can solder together. If you really want to grassroots it and make it happen, it will take some effort, but you can do it.
 
I'll be honest... I do it all the time. As a TD for a small community theater, if it doesn't involve soldering irons and gaff tape, it's not going to happen.

I have two subs right now. One is a Yorkville 10" with a fried amp, so I bypassed it and feed it 300w with a low pass set at about 80hz. The other one is a super-craptastic home-built particle board bandpass box from the trunk of some kid's civic with two Kicker 12" subs that I feed with about 400w in series to keep a safe impedance. Super hacked, but it sounds pretty incredible. I did have to glue the surround on one speaker. The bandpass of the box lets the excursion go a little wild around 60hz. I keep that second one far out of sight lines by putting it under the seating risers. A nice clap of thunder really wakes up the sleeping people, but they don't have to see how hideously ugly it is.

I would suggest just doing the research on crossover points that the boxes/drivers were designed to handle, then bi-amp it or fab up your own crossovers. Online plans are a google away, and parts express has crossover kits you can solder together. If you really want to grassroots it and make it happen, it will take some effort, but you can do it.

It comes down to "do I want this loudspeaker to work as designed, or does it just have to make some kind of sound?" I try to discourage the latter because the venue gets a collection of stuff that looks the same but can sound radically different, unit to unit, and that sucks, period. I understand if the option is "no sound at all" but it's a lot easier to make decent sound if the gear works as intended and designed.

Ya gots to do what ya gots to do...
 
So funny, I just had the same thing happen to me. 8" powered EV had its amp blow. Luckily I found this speaker by my complex's dumpster so it was 100% free and in amazing shape. Not sure who would throw away a $400 speaker.
So I'm forking out the $210 to Bosch to repair the Amp but its just a molex connector inside where the amp pulls out and I was going to try using a class T crappy amp with a passive crossover instead. In reality, it never has any live audio played through it, only background music in a small lobby area so I wasn't worried about too improper a crossover freq or overdriving it.
 

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