The jump from the Jr to the 70 is huge.
Stuff I've previously written....
I went from a Fiio X3 (Gen 1) to the AK Jr initially. The difference there was the detail was just so much better with the AK Jr (I was using Shure SE425s at the time). I did feel that it was a little light on the bass, although it wasn't muddy at all. With hindsight, that may have been the IEMs.
The move from the Jr to the AK70 was seismic in comparison. A much more forward presentation, and everything far crisper and clearer. Slightly warmer sound than the Jr too and better detail on complex tracks. Not sure what your musical tastes are, but with Dire Straits "Brothers in Arms" you could hear every note sing on the guitar. It's a similar tale with Pink Floyd's "Wish You Were Here" (album), and then straying into the heavier side of things Rage Against the Machine's "Bullet in the Head," the punchiness of the bass is more pronounced and doesn't roll off as quickly.
In my view, the AK70 gives a very balanced, precise sound - but I'm not one for messing with EQ settings.
