Key Differences

Both models feature noise cancellation, helping reduce background noise for a more immersive listening experience. Both headphones are equipped with capable drivers that deliver balanced sound output suitable for music, calls, and entertainment. There is a noticeable difference in weight (270 g vs 250 g), which may affect comfort during extended use. Both headphones offer solid battery performance, making them suitable for long listening sessions and travel. From a usability standpoint, both models provide a reliable and premium headphone experience. Both models support modern Bluetooth connectivity, ensuring stable wireless performance with compatible devices. The frequency response differs (15 Hz - 28,000Hz vs 5 Hz - 35000 Hz), which can influence how well the headphones reproduce lows, mids, and highs. Sennheiser HD 558 and Beyerdynamic DT 990 PRO are well-known options in the wireless headphone segment, offering a balance of audio quality, battery performance, and smart features. Impedance levels vary (50 Ohms vs 250 Ohms), which can affect compatibility and audio output when used with different devices.

Verdict: Both models are competitive, and your decision should be based on your usage needs and preferred features.