Electric Bill

I have been debating if I should just keep my system on all the time or turn it off when not in use. The problem is that I think my system sounds better when left on (though this could be entirely my imagination). It draws about 105W in stand by as well as in use so it costs about $30-$40 of my $180 bill.

That's about 40kW daily for audio only and so 1.2MW monthly. Enough to juice up the band in the 1000 seats venue. Your room is a-bit smaller.
Do you keep all of your amps on all the time?
Anyways, you are the champ so far... I'm somewhere between $7...15 monthly out of $80 bill that most goes onto climate control and home appliances.

I would estimate that my audio/video equipment accounts for about $50 per month.

My entire estate is solar and windmill powered.

My total electric bill per month Winter is $55. Summer (like August) is $90.
Of that, about $30 is my electronics left on 24/7/365.
Summer i am certain at least $15 of the added air conditioning is due to heat from my equipment.
So Summer: $45. Winter $30
(my heat is 'free' so it does not matter to the apt owners that my electronics heat up half the need for heat except Dec/Jan/Feb where the heat is really on all the time.

I can see big class A amps being left on 24/7 could add a hundred to a monthly bill.