What are some good noise cancelling curtains?

Some good noise cancelling curtains include The Wool Sandwich, Opulent Velvet, Sheer Stillness and The Big Guns. Some of these curtains block both sound and light.

The Wool Sandwich has a wool core sandwiched between two layers which acts as an air filter and sound absorber. The Opulent Velvet has noise sponge lining that cancels sound and allows light to enter the room. The Sheer Stillness has sound-absorbing polyester fabric. It's modified to block noise and let in light. The Big Guns blocks sound and light; opening this curtain allows in air and daylight. Noise cancelling curtains help improve work efficiency and peaceful sleep.