Hi Grace,
There are various types and levels of 'soundproofing' but please be aware that most will not completely block all sounds. For example, some levels of sound (high or low pitches) can still get through certain barriers. Fyi I'm not a sound expert, just a dog sanctuary director.
On the lowest/least expensive end of things, some people will try using music room foam. Keep in mind that there are fire safety concerns to this option, not to mention dog chewing/swallowing concerns, and foam on the walls is only mildly effective against sound bouncing, not sound blocking.
There are also different types of drywall products that are considered more sound blocking than regular drywall, as well as drywall sealers for the hardware holes and seams.
Then there are soundblocking foams (again, check with the fire department for fire safety).
One thing I learned when attempting to soundproof our rooms was that in order to get the most soundproofing possible, you need to apply the materials to every wall as well as ceiling and floor -- a complete envelope -- in order to get the best possible proofing. It's a big job, but I'm sure those who benefit from it would be very grateful to you. :)
Good luck and let us know how it goes? I personally would love to hear a before and after audio sample. :)
Rain
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