When providing sound, we
small-timers must use standard wall outlets instead of being able to tie
a power distro into the main breaker as is the practice in large scale
shows. A common problem is that the grounds of the AC outlets are
not at the same potential, which causes a ground loop in the system.
The Poor Man's Bar Distro improves or solves this problem.
The distro is comprised of four sections, each
section having a Neutrik PowerCon Inlet, Outlet, and Jumper Outlet
(which can also be used as a second outlet). Each sectionís
I, O, and J are wired in parallel. Each section is rated 20 amps total
input/output (or as limited by each house Edison supply outlet Ė often
15amps). The grounds of all the PowerCons are bonded (connected) to the
chassis, so that all of the grounds are at the same potential, to
reduce or eliminate the possibility of mains-caused ground loops. All of the
above will fit on a single pre-punched one-space rack panel, but itís
best to build it into an enclosed metal chassis. This setup will allow
maximum usage of the electrical supply of the typical bar, small
theater, or corporate meeting venue. (No two sections that are fed by
House outlets can be connected together, so no sparks.)
Owing to a lack of space in my equipment racks, I never envisioned that
the distro would be mounted in one. Should you wish to do so, you
could of course mount Edison outlets on the back of the distro.
This would eliminate the need for power strips in the rack. As
Decora Edisons mount in a single rectangular hole, that would be the
easiest solution - unless you can find cost effective round outlets
(which used to exist - I've not looked in recent years).
I later found that my hum problems were not a loop at all, but an open
negative signal conductor in one of the sub lines of my drive snake
(sometimes I used one sub line, sometimes I used the other).
(Check your cables once in a while!) I discovered this when I
chopped the 100' drive snake into four 25' sections. Three of the
four sections were open on that conductor! I've never seen
anything like it.