Until now we've reviewed many active noise canceling earphones, but they've been the large format circumaural or supra-aural type. I think this is the first time I'm reviewing a canalphone-type, earbuds and all, that offers active noise cancellation. And it’s from a familiar name – Philips. So here's my take on the Philips SHN2500.
Form Factor and Features
This unit is exactly like any other in-ear earphone, though with a lightweight black plastic case to house the active circuit. This is placed at the junction, or the breakaway point on the cord, which splits into two wires for each driver. This box has a largish slider switch on one side to turn it on; and just to add light on the detail, the exposed switch position is orange. The other side has the battery compartment, which seats a single AAA battery.
Two sizes of earbuds are provided, of the regular rubber material. The driver cases are small black cylinders, with a small aluminum ring on the opposite end, on the side which faces outwards while you wear them.
The wire is of medium length, though I feel the NC circuit box should have been higher up in the cord. They feel light enough to wear, and do not weigh you down. Overall they are as portable as any other earbuds, and will work well with pods and PMPs – after getting used to the NC circuit box lying in the course of the cord.
The rated response is 40-20000 Hz, sensitivity is at 102 dB, while the impedance is 72 ohm(hmm..). The magnet is made of neodymium, while the material of choice for the diaphragm is mylar.
Can I have the price please? 
