And the key to getting a competent electrician is....?
Word of mouth from others that have used the guy.
Quality workmanship abilities would be right up near the top of the list.
Ya the guy should be licensed, Bonded, and insured. But that is no guarantee how good of a job he will do.
NEC Code says, an installation shall be installed in a neat and workman like manner.... By whose standards? I guess the local AHJ?..... The inspector looks for code violations.... Not how good the job looks or how your audio system will perform.
Here is what Article 90 of NEC 2011 has to say.....
(A) Practical Safeguarding. The purpose of this code is the practical safeguarding of persons and property from hazards arising from the use of electricity.
(B) Adequacy. This Code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance results in an installation that is essentially free from hazard but not necessary efficient, convenient, or adequate for good service or future expansion of electrical use.
(C) Intention. This Code is not intended as a design specification or an instruction manual for untrained persons.
So if an electrician tells you his work meets code all he is really saying is that his work will meet bare minimum NEC and local electrical safety code standards......
A good example is VD, voltage drop, on a branch circuit line. NEC only gives a recommendation for addressing VD when calculating the wire size for VD. Addressing VD is not mandatory.....
If you tell the electrician you want a 120V 20 amp dedicated branch circuit installed for your audio equipment, per NEC he has to use a minimum wire size of #12 awg. The length of the branch circuit by code doesn't really matter. To your power amp it might....
We know from experience and the experiences of others that multiple branch circuits that feed audio equipment, connected together by ics, should be fed from the same Line, leg, of the electrical panel. A non audiophile electrician has been taught to balance his loads across the legs of the panel.
You the customer have to do your homework. There is a lot of good information out there. A good Electrician/Electrical Contractor will help you in the design, wiring methods, and materials that can be used to meet NEC and local codes.