I think the elements and backs of the KSN1016a's, KSN1001a's and 1005a's fit your 1038's. I think you can simply pull the back section of the 1016a and replace your 1038's element and back.

There are two versions of the larger 1800 hz piezo drivers. One version of each model had only a tiny 22 ohm 1/2 w resistor inside. The "Powerline Series" had a tiny lightbulb and poly switch (I think) to form a protection circuit that was good up to 400 w.

I had a 10 pc Tower of Power style R&B band that often played in the local civic center. Just a few blocks away was a large communications tower (Datacom) with a gazillion antennas and a major intersection. Our old Peavey PA amp would pick up radio signals at times, we could hear the voices at low levels. But a few times, we think it was HF oscillation from RF, completely inaudible, would toast the KSN1025a's (aka 2x6 horn) in our PA speakers.

When I say toast, I am talking smoke coming out of the horn, as if a smoldering cigarette were inside. Upon removal, we found the back cover melted. You will see the better "Powerline" version on the Martin site as Cat No 0934. We didn't have those... we had the cheapo versions.

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