Audio Gear

In-Ear Studio Monitor Headphones
These are really nice because they loop over your ears from behind and appear completely hidden to a front view camera. Great way to keep audio quality high when on calls but eliminate the distraction of large headphones.
MEE audio M6 Memory Wire In-Ear Wired Sports Earbud Headphones (Clear) (2018 version)

Great Sound While Still Hearing Your Co-Workers or Kids

I like this Koss ear clips. They let outside sound in so I can still hear things around me enough to know when I should stop the sound and talk to someone or tend to the kids. I also tend to just wear one side at a time for this same reason. The sound on these are awesome for when you do want great audio. They are also very cheap, only $14.
Koss KSC75 Portable Stereophone Headphones, Single, Standard Packaging

Microphones

Having a good lav mic or shotgun can help with better sound by putting the source closer to the mic or making the sound pickup more directional.

I use this one that has been very good for a lav mic.
Deity V.Lav Pre-Polarized Lavalier Lapel Microphone Omnidirectional Condenser Mic for DSLRs,Camcorders,Smartphones,Handy Recorders, Laptop, Bodypack Transmitters,Tablets

Sound Treatments

Use moving blankets and some woodworking clamps to clip up blankets where you need them. I’d recommend using several blankets to add to the density of the sound block. You can also put a blanket on your floor in front of your door to help block some of the sound from entering under your door.

I use these cheap moving blankets from Amazon
https://amzn.to/2HoAuUG

To hang up the blankets I use a Bessy spring clamp
https://amzn.to/31Ajceu

Use several blankets to make the sound block heavier.

An additional technique is to use some weather stripping to seal the gaps in your office door so when it’s close there is very little air passing through or sound would have to bounce several times to get through the gap. I bought some wide weather stripping and cut it in half. Since I have two doors I put a strip on alternating sides of where the doors meet, this creates a better seal. I was planning on using this or an under door sound block to also seal the gap at the bottom of the door, but haven’t got around to doing this yet, so far the blankets are doing the job good enough.

Weather stripping:
https://amzn.to/3kqCfPG

Door bottom sealer:
https://amzn.to/2ILF4Nd

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