Amazon.com: SENNHEISER PXC 550-II Wireless NoiseGard Adaptive Noise Cancelling, Bluetooth Headphone with Touch Sensitive Control and 30-Hour Battery Life, Black : Electronics
Sennheiser PXC 550-II
PXC 550-II | DIY-Audio-Heaven
Sennheiser PXC 550-II Wireless [28/38] Adjusting sound effects the equalizer
User manual Sennheiser PXC 550-II (English - 38 pages)
Amazon.com: Sennheiser PXC 550 Wireless – NoiseGard Adaptive Noise Cancelling, Bluetooth Headphone with Touch Sensitive Control and 30-Hour Battery Life : Electronics
Sennheiser PXC 550 Noise Canceling Bluetooth Headphones Measurements | Stereophile.com