Crossover makes amp go into protection mode

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Hi!

I've just assembled a pair of Volt 10 crossovers from DIY Sound Group.
However, I have a peculiar issue with one of the crossovers.

When hooking it up to the amp, it makes the amp go into protection mode.
The other crossover is fine, and I can't see any differences between the two :confused:

What could cause this? I've attached a bunch of pictures...
 

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I have a multimeter, but no idea how to use it :rolleyes:
How do I use it to check for a short?

Measure resistance between two points.

First, set meter to measure ohms, then touch meter tips together. This is the resistance of the leads. Anything measuring this low or lower, should be considered a short.

Do this with the crossover disconnected from the amp:

Touch the probe tips to points that you think ought not be connected. If they read OL ( open loop ) there is no connection.

You may read a higher ohm value between certain points. This implies there is a connection for DC to flow between those two points.
 
If you tested with unloaded crossover outputs, that might bring your amplifier to the edge of instability. Because of component tolerances, it could be just over the edge with one crossover and just before the edge with the other one. That is, neither crossover would then be broken.

On the first picture of the copper side of the crossover in the first post, it looks like the soldering of a wire between the upper two tieraps is not good, but it is difficult to see whether it really is loose. It might just be the shadow of the wire that makes it look like that.
 
If you tested with unloaded crossover outputs, that might bring your amplifier to the edge of instability. Because of component tolerances, it could be just over the edge with one crossover and just before the edge with the other one. That is, neither crossover would then be broken.

On the first picture of the copper side of the crossover in the first post, it looks like the soldering of a wire between the upper two tieraps is not good, but it is difficult to see whether it really is loose. It might just be the shadow of the wire that makes it look like that.

The bad crossover makes the amp go into protection both with the drivers connected and without, whereas the amp doesn't care with the good one (normal operation both with and without load).

Double checked now, and no loose wires anywhere. One of the solder points have a bit of a "dirty" / "burnt" tin. Measures fine tho, so shouldn't be an issue?

It's just one channel ? Does the speaker connected to it actually produce sound ?
Did You test on the other channel too ?

Tested both boards loaded and unloaded. With the broken board, the woofer and tweeter makes a popping sound when the amp goes in and out of protection mode.
 
If you switch (only) the crossovers between channels,
does the other channel's amplifier then go into limiting,
and does the original limiting amplifier now work ok?

If not, the amplifier itself probably has a fault.

The issue follows the crossover, i.e same issue on both channels.
The amp (ICEpower 300ASC) does seem to have independent protection for each channel (only the one with the bad crossover goes into protection).
 
There was a time when I had zip-tied down a coil, and the ratcheting of the part to the board allowed the urethane on 2 places of the coil to rub and short out. It is possible that the coil in the tweeter spot might be doing this. This could look like a short to the amp.

Later,
Wolf

That would cause it to measure 0 ohms I reckon?
Both coils measure ~0.8 ohms.
 
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