Review of the PSB Speakers M4U 4 In-ear monitors

We are starting to see various hybrid headphones and now IEMs coming on the market.  I enjoy my hybrid dynamic/BA Final Audio Sonorous IV headphone.  PSB Speakers has now released the first hybrid dynamic/BA IEM, the M4U 4.  Peter Pailis posted a review of the M4U 4 on  Peter believes that at $299 the M4U 4 is the best IEM under $600.

Review of the M4U 4