1176 Transformer Hum

Better show it the lyric sheet ?

Sorry, is the hum a constant level and is it low, medium htz? Have you checked all electrical and audio cords cross at right angles ? Is there a ground switch or star screw snd have you used it ? Do you have a star ground for your gear?

@keatthedog, and @ doubledog -

Thanks for sharing ideas. Moved the Seventeen away from other gear, hum persisted, tried an idea I had last week that worked but did not execute (I have little excuse for this)... put it on the same power strip, ergo, the same ground, and no more hum. Happy this worked because I like the unit.

Again, thanks for throwing out some ideas to get me going.


Craig

Sounds like you have a ground loop due to the AC power coming from 2 different sides of the electric panel.  The phase on each of the legs at the panel are reversed and will wreak havoc with 60Hz hums on analog audio gear.  All analog audio devices need to be on the same power leg.

Back in my youth I had a home studio I built in an old detached garage.  I ran a separate sub panel to the garage and put power outlets all around the inside.  This was before I knew about ground loops and such.  I had audio gear and electronic instruments all around the room that were plugged into different power legs.  I had 60Hz hums that absolutely could not be eliminated and I tried everything.  After much research I found out why and rewired the panel so all the lights and external outlets were on one leg and all audio gear was on another.  All my hum problems were eliminated after doing that.  That's probably why your hum went away when you plugged the 1176 into the same power strip as everything else.