Help with DIY dedicated circuit


I am wanting to install a dedicated circuit for my amp, but getting from my panel to the wall behind my amp is going to be difficult. As I was investigating in my attic, I realized that when I changed my stove from electric to gas, the unused 30 amp Romex 10/3 wire will reach within 15 feet of where I want the wall outlet. Do I install a junction box and run Romex 10/2 to the new wall outlet and use the 30 amp breaker? What is the best way to connect the wires in the junction box?
128x128jonandfamily
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For those who may not be aware, the many posts Jim (Jea48) has provided here over the years about electrician-type matters make it abundantly clear that his background and expertise in this area are second to none. Second to none not only at Audiogon, but I would feel safe in saying among electricians everywhere.

I for one have learned a great deal from his posts over the years, despite the fact that I have a very extensive background in electronic design. And the help he has provided to a great many members here has earned widespread recognition and appreciation.

Regards,
-- AlĀ 
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