Woof! Subwoofer issue

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xtian
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Woof! Subwoofer issue

Post by xtian »

My band thought we blew out a subwoofer last weekend, but no. It turns out to be an intermittent connection to the internal crossover. The wiring looks to be 24 gauge, so I'll replace it. But wondering, since we use a rackmount crossover already, any reason to keep the one inside the cabinet? I want to throw it out.
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NickC
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Re: Woof! Subwoofer issue

Post by NickC »

What's in it? Two-way, woofer and horn-compression driver?

If so, you could eliminate the passive onboard crossover, wire the drivers up to speakon jack plates and use the outboard active crossover. You'd need to match amp power up to the drivers so you don't blow up the compression drivers; don't want to feed them as many watts as the low-end drivers.
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xtian
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Re: Woof! Subwoofer issue

Post by xtian »

Sorry, missing data. This is just a single 18 driver in a cabinet. Simple. Trash the crossover, right?

Actually, it's not a xover, cause there is no other driver? Must be a LPF.
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xtian
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Re: Woof! Subwoofer issue

Post by xtian »

The cap is 100uF, and the resistor (inductor?) reads about 1ohm, so that's a 1,592Hz LPF.
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NickC
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Re: Woof! Subwoofer issue

Post by NickC »

xtian wrote:The cap is 100uF, and the resistor (inductor?) reads about 1ohm, so that's a 1,592Hz LPF.

Yep, a LPF. Ditch it, your active crossover has better filters. Do you know the frequency response of the 18" woofer, how high it'll go and the recommended x-over point? I run my 2-way system with the cross-over point at 2K.
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Re: Woof! Subwoofer issue

Post by vibratoking »

This is a subwoofer, correct? That should be crossed over somewhere around 100 to 300 Hz max. Using the resistance of the coil and the cap to calculate the 3dB point is not valid. You must use the inductance and the cap. It's a two pole low pass filter and the calculation is different.

But I agree with Nick, it is most likely that your outboard crossover has better filtering.
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xtian
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Re: Woof! Subwoofer issue

Post by xtian »

Sounds good. Thx, guys.
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