Audio Output Advice Needed.

[Zack Sporre]

(Edited) have an ignorant question. I have a Yamaha 1080 sound bar for my DVDs. I thought it would be nice to run my projector sound through this. I achieved this via Bluetooth for awhile. However, there is a slight audio delay which could be annoying at times. So I got a 3.5mm audio cord and ran it directly to my speaker output on both my Eumig 810 and my Beaulieu 708. However, on both projectors the audio is very low quality and also has a serious hum. What am I missing? What do I need to run it through to achieve good sound output? Thanks.
After taking to Steve (Reel Image) a little and testing things further. I am beginning to conclude it is some sort of ground issue. The hum is worse when I use an AC power cord with a ground wire for my projector. Also, I found it interesting, the low hum increases slightly even when the power cord is not plugged into an outlet but I plug and unplug it from the projector.

[Steve Klare]

For one thing the speaker output signal is probably too strong for your sound bar. I'm guessing it's looking for a line level signal at its input. The Eumig 800s have an Aux signal and your Beaulieu almost certainly does too and these are line level.

You may also be running into a ground loop, which makes for acres of hum. When you have equipment plugged into different outlets, the little difference between the third prongs on the two outlets winds up being part of your audio.

These can be sneaky. The first time I plugged a projector into an amp, I had monumental hum. The projector is grounded. The amp itself wasn't grounded, but it had an audio input from the TV (also not grounded). The TV (not grounded) was connected to the cable box (not either...). The cable box was connected to about 150 feet of coaxial cable which is connected to a grounded lighting strike arrestor next to my garage!

-So my projector was having a ground war with the cable TV company!.

What you can do as a trial is plug the projector into the same outlet as your sound bar. -at least get the "loop" out of "ground loop".

There are these devices called "ground loop eliminators". They take signal and ground from the source and provide signal and ground to the Amp. They magnetically couple the signals across so the grounds are isolated from each other.