Both models support modern Bluetooth connectivity, ensuring stable wireless performance with compatible devices. There is a noticeable difference in weight (318 g vs 238 Gm), which may affect comfort during extended use. JBL Synchros S300-A and SHURE SRH240A offer different noise cancellation capabilities (NA vs CVC), which can impact how effectively they block external noise. Both headphones are equipped with capable drivers that deliver balanced sound output suitable for music, calls, and entertainment. Impedance levels vary (32 Ohms vs 38 ohm), which can affect compatibility and audio output when used with different devices. From a usability standpoint, both models provide a reliable and premium headphone experience. Both headphones offer solid battery performance, making them suitable for long listening sessions and travel. The frequency response differs (10 Hz - 100,000Hz vs 20 Hz - 20000 Hz), which can influence how well the headphones reproduce lows, mids, and highs. JBL Synchros S300-A and SHURE SRH240A are well-known options in the wireless headphone segment, offering a balance of audio quality, battery performance, and smart features.

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