L200 Hi Frequency knob repair question

[wild78]

My high frequency control pots are loose in the cabinets. What is the process for tightening them up? Are there screws in the back inside with a flange of some sort to hold them in place? A person would have to inside the cabinets to do this, is it better to take the woofer out and go in that way?

[remusr]

Usually just a concentric nut on the shaft. Pot mounted from back of mounting plate, securing nut on front followed by the knob. Mounting plate "may" be screwed to rear of baffle and that could get loose. Unusual.

[hjames]

My high frequency control pots are loose in the cabinets. What is the process for tightening them up? Are there screws in the back inside with a flange of some sort to hold them in place? A person would have to inside the cabinets to do this, is it better to take the woofer out and go in that way?

First, lay the speaker on its back and remove the woofer so you can reach into the cabinet. The level control is surrounds by a label called a Foilcal. Underneath the factory foilcal are countersunk screws that hold a daughterboard to the back of the baffleboard. People have said to use a blow dryer to heat the foil cal, and peel it carefully off. You can then remove the screws and lower that daughterboard into the cabinet. Once its loose (tethered by wires) you can use wrenches to tighten down the nuts on the pots.