I recently got these ear plugs to use at night when I sleep: Amazon.com: Ear Plugs for Sleeping Noise Cancelling, Reusable Silicone Soft Moldable Waterproof Sound Blocking Earplugs for Swimming, Snoring, Working, Airplanes, Shooting, Musicians, 32dB Highest NRR, Green: Health & Personal Care

They do a good job blocking out all the background sounds that I can't filter out myself while keeping speech the same as it was before so I can understand what is being said easier.

I've never heard of the high fidelity earplugs before but now I'm intrigued by how they work.

Edit: I like the silicone earplugs because I have really narrow ear canals and regular shaped earplugs don't fit me well and usually fall out within an 10 minutes of putting them in. The silicone ones last all night for me.