Key Differences

Impedance levels vary (100 ohms (when noise cancelling function is used) vs 70 Ohms), which can affect compatibility and audio output when used with different devices. There is a noticeable difference in weight (220 g (Inclusive of Battery and Cable) vs 140 g), which may affect comfort during extended use. Audio Technica ATH-ANC9 and Sennheiser HD 25-1 II are well-known options in the wireless headphone segment, offering a balance of audio quality, battery performance, and smart features. From a usability standpoint, both models provide a reliable and premium headphone experience. Audio Technica ATH-ANC9 and Sennheiser HD 25-1 II offer different noise cancellation capabilities (Yes (Reduces Noise up to 30 dB) vs NA), which can impact how effectively they block external noise. The driver size differs between the two (40 mm vs NA), which can influence sound depth, bass response, and overall audio clarity. Both models support modern Bluetooth connectivity, ensuring stable wireless performance with compatible devices. Both headphones offer solid battery performance, making them suitable for long listening sessions and travel. The frequency response differs (10 - 25,000Hz vs 16 Hz - 22,000 Hz), which can influence how well the headphones reproduce lows, mids, and highs.

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