Can you point me at information about these subdermal transducers you're looking at installing in your head? That sounds insane, but I kind of want some.
The general consensus, after much experimentation, is that the targus isn't the best site because it just doesn't conduct loudly enough. Direct bone conduction via surgery of course works well, but then there is still the issue of power and amplification.
There's been talk in the past about a non-permanent dermal retainer that could do the same thing, and this could potentially be an all-inclusive package if done correctly. That's something I'd like to look into when I have the tools and money.
The targus and the temple are totally mid and high range. Try putting a 20W amped transducer on your jaw below your earlobe. You get VERY immersive sound. I see no way the targus implant could be worth it. I also don't see a way to put an implant on the jaw that would work because it's moving.
The spread between mid/high on the temple/targus and mid/low on the jaw are crazy though. When you have both it is full imaging that includes a space with a frustum inside your head.
Thanks for the body mod info! If you are looking at the implants I would highly suggest tying these positions I'm suggesting. I don't think it's worth the risk for the output!