Hum issue - driving me more crazy

Page 2 (Continued)
I have used cheaters in all possible combinations with resolution of most of the hum BUT not the residual in the right channel only.

I have disconnected the dimmers from the circuits in room->no help
Reversing amps and XOVER outputs -> no help
Ground lift change on amps->no help
Preamap powered off and XOVER powered off -> no help
Electrician has reevaluated wiring and says all is OK
Separate 20 amp circuit has its own ground
No lights are plugged into stereo circuit

Unplug interconnect at right amp -> RESOLVES HUM
" " " RIGHT XOVER OUT -> RESOLVES HUM

Bringing the IC to the right amp TO ABOVE the floor-> RESOLVES NOISE. In my unknowing frog brain, this implies something is inducing noise in the right sided IC (when under the floor - down about 12-16" is all though). But nothing can be identified so far

As I know not enough about electronics:
Unplugging or turning off preamp or XOVER does not help - > are these eliminated as issues causing ground loops etc when OFF? Or are they still part of a system with potential "current flowing" (even though "off")

Does disconnecting IC from AMP (or at XOVER) TELL SOMEONE WASSUP?

Perhaps, as a (sort of) simple solution - > Would balanced from XOVER to AMP resolve the issue regardless of cause?

Thanks

Elizabeth-> same IC. My cables are well and DOUBLE shielded.

Gs5556-> No fluorescent under the floor. No LED

Balanced appeals to me as best easiest possible solution. Should help with noise anyway

Now if I had only made the holes in the floor for the IC's bigger.... but who knew?

Can one build a balanced cable (for a trial anyway)?

If so one can someone tell me what to get at Altex or Frys or online. I can easily pull another cable behind the IC but balanced XLR connector will be problematic right now due to hole circumference.

Thanks to all for help, psychiatric consult, etc

Dan_ed

If you are going to lift the ground (cheater plugs) try to do that on the preamp and let everything ground through the amps. >>>>>>>>Will try but I think this worsens other hums

If you haven't already, try to plug both amps into the same outlet and see if the hum is diminished.>>>>>>NO help

Matter of fact, you may need to plug everything in your system into one outlet to see if this helps even more.>>>>>>>>Will try

Try swapping the ICs between amps and see if the hum follows the change. >>>>>>No help

When you can, try turning off all of the breakers in the house except the one feeding your system and see what happens. >>>>Have tried without obvious source as I recollect but will try again

Jea48

*How long is this IC cable? >>>~ 15'
*What type of cable supports are used under the floor? Plastic? Metal? >>>>>>>>Blue flex hose supported with plastic hangers
*How often is the cable supported, distance between supports?
>>>>>>>>About 5' apart as I recollect
*What is the area, space, under the floor? Basement? Crawlspace?
Space is under entire first floor of house ~ 1800' I guess
Room is 15X20 -sort of isolated from other parts of house Crawl space is ~ 18" dirt to bottom of rafter

Magnumpi205 - > I don't disagree and will try this
Shayl123 - I have -> no help
Rwwear -> I have -> no help

BUT I replaced right channel with balanced IC's tonite AND SO FAR NO NOISE. Can even use the dimmers in room that were clearly problematic. Able to remove the cheater plugs without hum (which was an issue before)

Not ready to declare victory (as there was variation in level of hum) but things are looking up so far.

MAGIC SO FAR

Rwwear - hum started at time of new XOVER. BUT this was also same time that I "buried" the IC's under the floor and got new IC's. Thus multiple simultaneous changes. IC's above floor are great.

Ozzy - No TV or SAT in system - LP, DAC and CD player are only sources

BALANCED cables has fixed all issues even allowing me to use the dimmers in the room without a peep. Even slight hum in Vinyl subsystem (2 chassis phono preamp) is gone.

I don't know enough electronics to understand what "I fixed" (or more likely unbroke) but the end results are outstanding for about $120.00 worth of cable and connectors. All I can say is in my application/room/system -> Balanced IC's are great.

Thanks to all. Have a memorable Memorial weekend