Double Bass Help me troubleshoot my broken Berg IP112

[aaronallen]

Hey, my amp is broken and I'm hoping someone can help.

So last night while unloading gear for my new years eve gig, the handle on my Bergantino IP112 snapped and the cab hit the pavement pretty hard. Once i got it plugged in, i noticed that theres no sound unless i play hard which causes a distorted buzz. Luckily, i was able to do the gig without amplification.

I've got the thing taken apart and there are 3 basic components. 1) the amplifier 2) a small circuit board 3) the speaker. I've determined that the amplifier is working by listening to its lineout port and there is no distortion.

I've examined the surface of the speaker and i don't see any damage. What I want to know is whether there could be some internal damage to the speaker that is causing the distortion.

If not, my next step will be to remove the circuit board and test all its connections but I don't want to do this unless I know for sure that it isn't the speaker.

 

[DoubleMIDI]

Maybe a broken solder connection or a heavy part that is only fixed by the connection wires (like an electrolytic capacitor) might have been damaged (by broken internal electrical connection) or something similar.

I would check the power lines for the power amplifer part first, then you know if the failure is in the power supply or the power amplifier.

Sometimes it is as easy as a cable connection failure, so check all cable connections first. Sometimes it is some corrosion at a connector, so plug them out an in again a few times. (But this usully only happens after several years after the unit was built.)

 

[GrowlerBox]

I would not have thought that a damaged electrical connection would cause a buzz on heavy playing -- it sounds to me more like damage to the speaker mechanism (not the cone), for example, a broken suspension allowing the voice coil to contact the magnet. If that's the case, you'll almost certainly need a new speaker.

 

[DoubleMIDI]

This is possible indeed, but in my opinion with less probability than the electronics.
Get a second speaker/box and plug it into your amp. listen to this speaker and if this one is fine, then it is the speaker (coil) and you need a new speaker.

 

[aaronallen]

It's the speaker. The amp is working fine and I checked all the other connections. Thanks for your help.