Sony boasts that its Sony MDR-NC500D headphones are the first to use digital noise-canceling technology. While a built-in digital equalizer is a step in the right direction, these headphones don't do much more than many of the other analog noise-canceling headsets we reviewed. They still provide impressive sound and noise reduction, but they don't offer much playback time and are incapable of playing in passive mode.
When using the MDR-NC500D headphones, you can adjust the noise cancelation manually or let it happen automatically. Sony has chosen Airplane, Bus and Office as the three different settings that you can choose yourself. Each one of these settings creates a frequency tailored to interfere with the average ambient noise of those environments. You can turn on the AI mode and let the headset create a noise-cancelation frequency specifically for the area you are in. These headphones can reduce up to 99 percent of ambient noise. This translates to 20 decibels at 160Hz, so you won't have to turn up the volume to drown out background noise.
The MDR-NC500D noise-cancelling headphones have a frequency response of 5Hz to 24kHz. The average person can hear frequencies between 20Hz and 20kHz, so this audio accessory can play the subsonic and supersonic sounds that are found in some music. They also have a sensitivity of 102 decibels, so you shouldn't hear hissing or distortion when you are listening at higher volume levels.
One unique feature of the MDR-NC500D is the monitor function, which allows you to use the built-in microphones to hear the noise around you. This makes it so you don't have to take off the ear cups when someone starts to talk to you. However, in order to use this function, you need to keep the button on the headset pressed, which can be annoying if you have to do it for a long time.
Other noise-cancelation headphones are able to function in passive mode, but once the batteries in this Sony MDR-NC500D headset run out, your music stops. They cannot be used as normal earphones. Active noise cancellation has to be on to listen to anything. This is a problem for those who don't carry spare batteries in their pockets.
The internal lithium-ion battery only lasts for 16 hours of playback. If you use two AA batteries along with the lithium-ion battery, the playback time rises to 28 hours. This is still significantly less than other products such as the Sennheiser PXC 350 and the JVC HA-NC250. The low battery life and the inability to play in passive mode are a few of the reasons why these noise-cancelling headphones are only slightly above average.
This headset shows the future of noise-cancelation technology. By switching to digital, these headphones create new possibilities in sound. However, this digital technology is still in the initial phases and doesn't perform as well as it could. The sound quality is quite good and the headset is able to block out most ambient noise, but the operating time is low and there is no passive play option. The Sony MDR-NC500D is a set of high-quality noise-canceling headphones that only need a few improvements to be excellent.
