The method of attachment for the SDA SRS 1.2TL side panels has been somewhat of a mystery. One owner said that it took him a whole week to figure it out, but he would not tell us how to do it unless we sent him a special request. Some owners, for fear of breaking something, will not venture an investigation.
While it is commonly thought that the SRS side panels are glued on (like the smaller SDA 1C and SDA 2B), they are actually held in place by trelocks similar to the ones that hold the grille panels in place. The side panel trelocks are different in that they are ribbed and fit much tighter. I used a 1-1/2 inch metal putty spatula to gently pry off the side panel.
Figure 1. Side view of SDA SRS 1.2TL.
Figure 2. SDA SRS 1.2TL with side panel off.
Figure 3. SDA SRS 1.2TL side panel trelocks.
The SDA SRS 1.2TL side panels are held in place with eight ribbed trelocks.
Figure 4. SDA SRS 1.2TL side panel front.
The wood strip is oak veneer over MDF. The side panel frame is a composite wood material like the grille frame. The side panel fabric is stretched over the frame and then the wood strip is laid over the fabric and set into a notch in the frame. The wood strip is secured with nails from the back side.
Figure 5. SDA SRS 1.2TL side panel rear.
I do not know the reason for the rectangular cutouts in the side panel frame. This makes the side panel fabric more vulnerable to damage. Perhaps there is some sonic benefit. Perhaps it was a weight saving measure. The panels weigh 11.5 pounds each.
Figure 6. SDA SRS 1.2TL side panel rear.
The wood strip insert on the front is held in place by tiny finishing nails (arrows). There are countersunk screw holes near the nails, but they are not used. Cost saving perhaps? Maybe Polk originally used screws but switched to nails. If you ever have to or want to replace the side panel fabric, it will be a lot of fun prying off those nailed up wood strips!