Do you buy Insurance for Stereo Equipment?

I guess most homeowner's insurance policy doesn't cover the entire (expensive) system for some folks. Anyone buys insurance just for the stereo equipment? If so, who do you buy it from?
Such insurance is very expensive as it needs to be underwritten in a special policy form. Even then, they try to cap any one items at a max of $5K. To get the proper insurance you need to provide a detailed schedule, and yes, the underwriter will come to look at the 'stuff'. I have a special policy rider that covers my equipment and media. Cost for the rider is now $2300 a year. The policy max's out at $325,000.
My agent, who is a friend told me my equipment was covered under the homeowners policy and the equipment did not need to be scheduled. I explained the cost issues, and he said my policy had enough room to cover all my household items plus my system. I decided to write all the equipment with serial numbers and replacement costs down and emailed it to myself so I can retrieve it if there was a fire.
Depends on the Carrier. There are standardized polices but there are also standard endorsements which can alter that policy. I have had USAA for 20 years and it is excellent. Before I owned, I rented and when I rented I had two break-ins and USAA replaced $20K and $18K in audio gear respectively, without hesitation (full replacement value).

Now I own and I asked USAA what I need to have a separate rider for, I was told jewelry, so i got a rider for my watches and my wife's rings. I then upped the "contents" coverage to 75% of the home's reconstruction costs. Which, if I have a total loss would replace all my "contents" gear included.

As long as your policy does not have a specific limit on "electronics", it will be covered as a "content". If your policy does have a limit on electronics, pay for a rider if you need additional coverage.

Or go bare and hope for the best....
no need, coverage C of the policy is for unscheduled personal property and is a percentage of coverage A, which is your dwelling. it's a pretty big number. however, take photos, scan your receipts into computer and paper receipts in a fire box. if you have replacement cost coverage on personal property it's insured for fire and theft and your insurer will pay to replace your items. they typically pay on each item on a depreciated basis and when you prove you replaced then they provide the "holdback" money that is the difference with full replacement cost.

Do your friend and your friendship with him a favor and get this in writing. I don't know of a subtle way to ask this from him, but lot's of Errors and Omissions claims start out with, "well, I had this friend".