Disaster

Why would you not file an insurance claim and have the insurance company either replace the damaged components or contract out to a company that specialized in electronic remediation?

If you attempt the rectify the situation yourself, you may jeopardize your ability to file a claim at a later date because the insurance adjuster may not be able to differentiate between the fire damage and the damage caused by your failed attempt i.e. you made it worse.

File a claim and have the damage on record and don't attempt any repairs etc. until the insurance company has assessed the damage.

I would file a claim. And I would contact servpro. 

N

WHAT EVER YOU DO DO NOT ENERGIZE ANY OF THAT EQUIPMENT until each piece if fully cleaned!

The soot will be partially conductive and could at least destroy your gear from the inside. Worst case it may start a fire again.

Be certain the restoration firm really knows what it is doing as the wrong cleaners can actually cause the soot to get more embedded in the electronics. Also wrong cleaners can ruin contacts in switches, etc. Serious electronics assembly/repair houses have automated DI- based cleaning systems designed for electronics - the good ones will seal switches, etc. prior to wash with removable material.

Just a word of warning to our fellow music freaks.  If you have a high(er) end system, you should talk to your insurance agent.  Make sure you have FULL REPLACEMENT coverage on your house and contents.  Otherwise if you make a claim, they will prorate everything according to it's age and value.  Or you can have a rider attached to your home owners policy to cover the cost of replacing your system or any part of what's damaged.  I had the top half of a  tool box stolen from the garage, and with the full replacement insurance, they bought me $10,000 in Snapon tools, with no questions asked.

I would be concerned about the cause of the fire.  Did it start with the stereo system?  If so, there may be irreparable electrical damage.  As some one else said, soot is one thing, but heat from the fire is a real damaging event.  Heal up, good luck.