I initially bought the Creative HN-700 as cheap noise cancelling headphones to allow me to work in peace and enjoy my music in my noisy college dorm. The headphones sport a standard frequency response of 20Hz to 20kHz, the limits of human hearing. The sound quality is definitely not as great as those produced by expensive Bose or Sennheiser products. However, for this price, it definitely is a bargain. The noise cancelling feature requires 2 AAA batteries and does a good job at blocking background noises but not enough for close noises. It definitely does the job on airplanes droning out the loud engine noises and even comes with an airline earphone adapter. One particular note to make is the comfort. These headphones will feel great for about 2 hours of continuous use. After that however, my ears begin to feel uncomfortable having these cans on. All in all, for the price it is definitely worth it as basic pair of noise cancelling headphones.