Welcome,
Aristo track and USA track are identical, just different tie color, shop around for the best price as track prices have become one of the biggest inititial costs getting started. Both tracks comes with little hex head set screws that bind the joiners and the rails together, they are kind of a pain as the hex screws are really small but once you get the hang of installing them they work quite well, a little LGB conductive grease inside each joiner also helps conductivity a great deal. The rail clamps, either Hillmanns or Split Jaws are best used at turnouts, that way you can unclamp a switch, lift it out for maintanence and replace it without disturbing the surrounding track.
General rule the bigger the power pack the better, can't say if its too much power for your sound system, so hopefully someone else can answer that.
Be warned about that Atlantic, the motor block can come loose, check out George Shreyers website for tips for maintaining the Atlantic, follow them and the engine will run as reliably as anything out there.
http://www.girr.org/girr/
Good luck
Have fun with your trains
Jersey: Just chiming in to echo Vic’s comments. I have no experience with the “little hex head” joiner, but have heard it makes good electrical contact, just hard to remove. Rail clamps are most assuredly well worth their cost. They provide both excellent mechanical and electrical connections. The two main brand names are “Hillman” and Split Jaw” and there is a simpler and more economical new comer (sorry, don’t recall the name) out there, have not used it but the design is simple and should work well. I would double echo Vic about using ONLY rail clamps on your switches (turnouts). Makes for easier maintenance and upgrading.
Tom Trigg
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