Fisound YUIN PK2 Traditional Design High Fidelity Professional Dynamic Earphone HIFI Stereo Headphone Ultimate traditional design with top sound quality. Driving by a head-amp, or even some high output portable audio like Ipod or Iriver, it can give you a feeling as top grade hifi headphones, not like average tiny earphones at all. Hi-fi headphone grade sound stage. Transparent, smooth sound. Comfortable traditional design, NOT in-the-ear. Ultra low distortion, high impedance for hi-fi or professional. 16Ohm low impedance for high grade portable audio.