Persistent Rattling Noise in Neumann KH750 DSP Subwoofer – Need Advice

[574stereo]

This sounds like a slipped magnet. If you drop/shock a driver with the diaphragm pointing sideways (as they are usually orientated in most speaker designs), the magnet can shift and ‘lock’ the voice coil and cone in place.

 

[respice finem]

Reminds me of the broken cinema speaker recently tested... Apparently the boxes get thrown around in transit.
Any option to fetch the replacement personally @Thomann? I would rather, before I get the next broken one.

 

[arescec]

Reminds me of the broken cinema speaker recently tested... Apparently the boxes get thrown around in transit.
Any option to fetch the replacement personally @Thomann? I would rather, before I get the next broken one.

It is a 1000km trip so I would say no. In contact with Neumann and hopefully they get my first speaker soon to analyze. I might get one locally from a different shop but there is always a worry when buying in store as you do not have the return options. Might ask that they test it in store.

 

[arescec]

Good news, my 4th speaker is working as intended first try. This time they sent it directly from the factory and tested beforehand.
The weather did get much colder so I wonder if it was a high temp issue causing the glue on the magnet to soften in previous ones, as most of the issues they had were from the southern countries. They do leave packages outside in the sun here.