Another pair of these TZ-9LTD came about for cheap and I have them here. The original mids are trash, but they can be repaired in Japan for ¥30,000 per (in Magnesium).
I have a pair of Be TAD drivers here, all similar parameters as the original, only with the Be goodness. But they don’t mount the same. So mod time!
To mount them using the back mounting system the originals had means drilling the backplate and thread tapping the holes. It’s nerve wracking because there’s a chance for a lot to go wrong.
I bought the necessary tools and measured the depth of the holes on the originals. Got the drill stopper and put it on the bit. Made my midrange driver jig up so the screen and dome don’t contact anything.
Today I did the first hole. The bit type is a wedge head, it bites slowly do things don’t bind or worse crack. It took FOR EV ERRRR to drill, but I got there. Then the three taps and special tapping wrench sloooowly to create the threads.
Success! This will work. However I am buying a tabletop drill press for the remaining 11 holes. I get seven turns of threads to the bottom of the threads so it’s a good bite.
In the cabinet, there is a cutout where the original driver was countersunk. This one will not do that. So I measured and found square cut o-rings and dang if they don’t fit like a glove. I will put two rings of Mortite behind the ring to lift it above the baffle so the flange of the mid never contacts the finished surface, and so it’s sealed and doesn’t buzz. Shown is one in the groove and then one for size.
The idea is for all of this to be reversible without a trace.
Some pics from beginning to now.
I have a pair of Be TAD drivers here, all similar parameters as the original, only with the Be goodness. But they don’t mount the same. So mod time!
To mount them using the back mounting system the originals had means drilling the backplate and thread tapping the holes. It’s nerve wracking because there’s a chance for a lot to go wrong.
I bought the necessary tools and measured the depth of the holes on the originals. Got the drill stopper and put it on the bit. Made my midrange driver jig up so the screen and dome don’t contact anything.
Today I did the first hole. The bit type is a wedge head, it bites slowly do things don’t bind or worse crack. It took FOR EV ERRRR to drill, but I got there. Then the three taps and special tapping wrench sloooowly to create the threads.
Success! This will work. However I am buying a tabletop drill press for the remaining 11 holes. I get seven turns of threads to the bottom of the threads so it’s a good bite.
In the cabinet, there is a cutout where the original driver was countersunk. This one will not do that. So I measured and found square cut o-rings and dang if they don’t fit like a glove. I will put two rings of Mortite behind the ring to lift it above the baffle so the flange of the mid never contacts the finished surface, and so it’s sealed and doesn’t buzz. Shown is one in the groove and then one for size.
The idea is for all of this to be reversible without a trace.
Some pics from beginning to now.
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