I would keep your PDT and try a different dac. You have a nice transport. Maybe try a newer ML dac. I used to have a #36 and liked it. Of course it is older but still a good one. Not sure what your budget is but I would think that newer dacs will be better than the PDP 3? Just my opinion of course.
You will get tons of opinions here so be ready...lol.
You will get tons of opinions here so be ready...lol.