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How to disperse avail. amperage?

I am going to soon be the proud papa of a designated listening room. Yes, it is the culmination of a 30+ year dream, but that's another thread. My question is : how exactly do I "divvy-up" the available electric into the room? I am converting a 13' x 18' detached garage which started out as uninsulated studs on the interior only shell, on a concrete slab. The exterior walls are approx 3/4" planking (built in the 1940's) with recent vinyl siding. I built a shed to house all the important stuff and ditched the rest. I had a new roof put on, as well as new leaders and gutters. I also had a side entrance door installed. I plan on removing the worn main 'big' door and removing the interior tracking for it, then i nstall a new dummy door, permanently affixed. Inside that I'll stud out an interior shell wall , then insulate and drywall it. I am well on my way with much of this already. I'm having an electrician come today to discuss running a 125amp sub panel from my main house's [recently upgrade] 200amp panel, out to the garage. this will include an 18" trench to run the cable, and I'll probably add a "cable box" cable too...When I have the box installed it'll be 125 amps. I'm expecting the main breaker on the house side of it to probably only be 100 amps? as well as the main breaker on the sub panel to only be 100 amps too... mostly because the 100 amp breaker is 1/3 the $300 cost of the 125 and I can't imagine I'd be drawing that much current all at one time?
I would like to have a separate breaker for "all lighting", as I plan on using dimmer switches and a reasonably extensive amount of light.
I will also be installing at a later time, when $$$ allows, a ductless A/C & heating system that can use a 15amp service (draws 11amps max). I was thinking it would be nice to actually provide a 20 amp line to this if I had the extra available.
I want a dedicated line for my analog pre, turntable, and analog misc (my electronic crossover)
I need a dedicated digital (multi players, Dacs , jitter boxes, SACD, etc
And since I am TRI-amping my speakers I need a dedicated for my tubed monos
A dedicated for 2 sub amps
A dedicated for my mid/tweeter amp
At 20 amps for each, except the lights,this adds to 120 plus the lights. Can I use a 10 amp on the lights for a total of 130 and be OK? Should I lessen the digital or analog only to a 15A for one of them? Any combination you can imagine would be a helpful suggestion. Thanks! Happy Lissn'n
lissnr
jea48
4,659 posts
 
The overall [cable length] distance from main box to sub panel will be about 50'
That's a far cry from 110' you posted earlier......
If the run is only a total of 50' then #4awg copper should be fine.

As for the separate ground...I'll ask my electrician (who came highly recommended from a contractor friend of mine)and who claims to be fully licensed...what I will do there.
Ya, post back his response if you would.

The Hubbell I/G outlets can still be used anyway, yes? Even if they're simply grounded back to the sub panel's standard grounding bar?
Unless you just like the orange color of the receptacle why did you spend the extra money for isolated ground receptacles?
Isolated ground receptacles are used in commercial and industrial facilities where EMI noise on conduit, metal studs and steel are a problem. I assume you will be using wood studs with MN-B cable and plastic rough-in boxes.

Essentially the non IG Hubbell will work just as an IG ground type in your instance.

For the Power Amp/s I personally would go with the Hubbell HBL8300H ("H" stands for non plated)
jea48
4,659 posts
 
I would recommend "Lutron" Dimmers!
lissnr OP
365 posts
 
Whew!! I feel much better.... 50' shouldn't be a problem w/ the 4G. Thank you!
Should I still minimize the use of A/C while listening I guess?
I looked up those Lutron dimmers... they look great. They'll all be on a separate dedicated 15A line so I don't expect an impact of their use on my main system??? (as this is mainly why I'm going separate lines in the first place).
I'll let you know what my electrician says about the isolated grounding bar/from the I/G outlets. Thanks again.
jea48
4,659 posts
 
I'll let you know what my electrician says about the isolated grounding bar/from the I/G outlets. Thanks again.
Lissnr


It is a Myth that the earth has some mystical magical power that sucks RFI/EMI noise from an audio system.

Though I do not advocate lifting the equipment ground , no equipment ground for an audio system seems to be the best.

More and more audio equipment manufactures are building their equipment with double insulated AC power wiring thus eliminating the need for the safety equipment ground.
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shadorne's avatar
shadorne
7,477 posts
 
Jea48,

Wow thanks for this info and link to presentation paper from Whitlock. An excellent summary. My personal experience matches this exactly.

1) Items not plugged into the same breaker/mains socket but coupled together sometimes give problems hum/hiss - it can be a significant issue, pain in the @#$%!.
2) I have found XLR balanced is by far the way to go for the least troubles - but this is sometimes not perfect - now I know why - real world imbalances.
3) If I ever get a nasty hum/hiss problem I now know to look for a Jensen transformer such as the ISO-MAX® PI-2XX.
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