Sony’s newer (ish) Hybrid design, the little brother, the Z5, it has plastic body, and lesser quality tweeter (Z5 has the super tweeter). but otherwise, a much better deal for one looking for Z5/ IER Z1R type of sound 
Sony’s newer (ish) Hybrid design, the little brother, the Z5, it has plastic body, and lesser quality tweeter (Z5 has the super tweeter). but otherwise, a much better deal for one looking for Z5/ IER Z1R type of sound