Review on Upgrade Your Studio Gear with Audio-Technica ATH-M40x Professional Studio Monitor Headphones: 90-Degree Swiveling Earcups, Pro-Grade Earpads/Headband, and Detachable Cables by Indal Kumar ᠌

Absolutely not suitable for a phone or an inexpensive player. If you want to listen with them, you will have to buy an amplifier. My LG G4c doesn't rock them at all. no bass and no volume. The sound from my Sony for 2500 from the phone is better. But by connecting to a computer or through an amplifier, the sound immediately takes on a color. The bass starts to pump. After listening from the computer, I don’t want to take the phone from the old Sony)