DI box hum

[jbaileypro]

Hey all,

I have a little problem with rack-able DI boxes. They have a humm but the guy I borrowed them off said that you just need to connect the earth wire to the stage box to make it go. I did and it made no difference at all! I tried looking for the manual but it looks like they don't exist! I did take a photo for you all though!

 

http://web.me.com/jbaileypro/DSC00102.JPG

http://web.me.com/jbaileypro/DSC00103.JPG

http://web.me.com/jbaileypro/DSC00104.JPG

http://web.me.com/jbaileypro/DSC00105.JPG

 

Cheers,

[paulears]

In most cases, these things are designed to float. The point of the DI box is to provide isolation, so if they are in a rack like this, then the chassis of each is already connected to the next one by the rack metalwork, so the rear ground connection may just be doubling up.

 

Do the ground lift switches change the hum at all?

 

First step is to disconnect every one bar one. Start with that one on it's own and check for hum. If it's clean, add the next - the point where the hum starts again is what we need to know, and a diagramme of how it's all connected would be useful.

[Wilflet]

The manual for the dib 106 is here. page 2 for english

 

the img-stageline site dosnt mention your 104, but the 106 is a 4ch box with all the same connections and switches as your picture so I'd guess they changed the name (or made a minor change that dosnt matter for your purposes)

[jbaileypro]

Thank you both! Ive got it all sorted out now, I just removed the earth and that cleared it up a bit. The main problem is that I was using a guitar that was actually dogie, I did some re-soldering and wolla! all works now. I found this by just plugging me ipod in and all gone.

 

Thank you for manual as well, it will give me some more detail into it.

 

Thank you all!