Specifications

HEX CAM SPACER INSTALLATION AND ADJUSTMENT
FOR THE LFT-8b
Tools needed:
5/32 Allen Wrench
7/16 Open End Wrench (aluminum recommended)
INSTALLATION
1.) Remove machine screws (4) and spacers (8) at the 4 centrally located
crossbars along outside edge of diaphragm frame (opposite tweeter) taking care
not to damage diaphragm. Loosen machine screws at points B in Figure 1 three
turns.
2.) Install hex cam spacers at locations shown in Figure 1 making sure cam
portion fits into hole in frame. Gently prying outward on crossbar will allow
clearance for hex cam spacer.
3.) Replace original spacers at remaining 5 locations. Replace machine
screws and run down to within a couple of turns of being tight, making sure cam
spacers stay in position. If screw will not thread into crossbar due to
misalignment, turn hex cam spacer until alignment is reached.
ADJUSTMENT
Loosen machine screws along outside edge of diaphragm (excluding screws at
each end) approximately one turn. Lightly torque hex cam spacers. Silver line
on hex cam spacer indicates high point of cam. By moving this mark towards the
outside of the midrange unit, diaphragm tensioning will increase. Excessive
torque will result in exceeding the elastic limit of diaphragm, which could result in
tearing. Over-tensioning will also raise the resonance of the diaphragm. If
wrinkles are present, adjust hex cam spacer until they are no longer evident. If
wrinkles are not present, look for traces on diaphragm to move slightly outward
while tensioning. Try to obtain an equal distribution of tensioning between the 3
hex cam spacers. Once this has been done, tighten all 6 screws.
Appendix A
33