nilknarf
New member
Just thought I'd post a success story with a buzzing Grotto sub...
My brother purchased a new Martin Logan system that featured this Grotto sub and a pair of Aeon speakers. He gave me the sub about 6 months ago stating that he had never been thrilled with the constant buzz the thing emitted from the very start, and when he built his new house with large open expanses of hardwood floors he simply didn't want to be bothered.
So I finally plugged it in to diagnose (power only, nothing plugged into the inputs) and sure enough- buzz. Pulled everything apart on the subwoofer- caps look good, no signs of heat, dust or anything... unplugged everything, worked the connectors, plugged it all back in. Buzz. Then I hooked everything up while it was all apart (speaker cone away from the cabinet, amp away from the cabinet) and plugged it in again... suddenly, no buzz from the speaker cone! Put my ear to the cabinet and sure enough- the buzz was mechanical and clearly coming from the toroidal transformer so I checked my house circuits for half-engaged dimmer switches and realized I have an old x-10 extender for a home automation setup plugged into an outlet, pulled it thinking maybe it was feeding DC into the front end of the transformer... still buzzing.
Bringing a very long story to a close, I removed the transformer and noted that the two rubber gaskets used to mount the transformer to the cabinet were a bit stiff and dry-feeling, so I cut two new gaskets out of a sheet of 1/16" rubber I had in the shop using the originals as a template and added them back in addition to the originals. Put it all back together again, and voila! No more buzz!
I hope this helps someone else who may be experiencing a buzzy Grotto!
My brother purchased a new Martin Logan system that featured this Grotto sub and a pair of Aeon speakers. He gave me the sub about 6 months ago stating that he had never been thrilled with the constant buzz the thing emitted from the very start, and when he built his new house with large open expanses of hardwood floors he simply didn't want to be bothered.
So I finally plugged it in to diagnose (power only, nothing plugged into the inputs) and sure enough- buzz. Pulled everything apart on the subwoofer- caps look good, no signs of heat, dust or anything... unplugged everything, worked the connectors, plugged it all back in. Buzz. Then I hooked everything up while it was all apart (speaker cone away from the cabinet, amp away from the cabinet) and plugged it in again... suddenly, no buzz from the speaker cone! Put my ear to the cabinet and sure enough- the buzz was mechanical and clearly coming from the toroidal transformer so I checked my house circuits for half-engaged dimmer switches and realized I have an old x-10 extender for a home automation setup plugged into an outlet, pulled it thinking maybe it was feeding DC into the front end of the transformer... still buzzing.
Bringing a very long story to a close, I removed the transformer and noted that the two rubber gaskets used to mount the transformer to the cabinet were a bit stiff and dry-feeling, so I cut two new gaskets out of a sheet of 1/16" rubber I had in the shop using the originals as a template and added them back in addition to the originals. Put it all back together again, and voila! No more buzz!
I hope this helps someone else who may be experiencing a buzzy Grotto!
