When we first got our tandem it had 36 spoke wheels with cheap SS spokes. Almost every time we went out we broke spokes on the chain side of the rear wheel (the most tension). I finally had them replaced with DT (The best then) spokes which helped some but eventually had new wheels built with 48 spoke Rino rims. The shop that did the work uses a tensometer which is the ONLY way to get them truly even and 12 years later they are still dead nuts on.
OK why the insistence on using a tensometer. On my road bike I had new wheels made and the shop has GOOD REPUTATION. but they had to be "trued" almost every week. Took them to the shop that does truing with the tensometer and they had to replace the spokes and true the wheels. 13 years later they are still true.