1. Combining Balanced Signals

Hi everyone,

I'm just wondering if anyone can help by telling me exactly how the hot and cold signals in a balanced cable are, and can be combined together. I understand the principle of a typical dynamic microphone and XLR cable combination up to the point where the cable is plugged into a preamp and the male connections meet the female ones and one of the signals is inverted but what happens next? Do all three connections simply combine by twisting the wires together or similar?

Also could you combine the hot and cold signals in a balanced cable by simply twisting them together? I appreciate that combining them without inverting the phase of one of the signals would give you no sound, however I am interested to know!

Many thanks,

J

2. hi jimi
what happens in a balanced xlr is this - both cables(+ and -)transfer the same signal, but with a reversed phase. this means that if you combine these 2 together their opposite signals will cancel each other and what you will get will be 0 signal(no sound).
well, the signal with opposite phase flows on the cable, the 3rd wire - the ground(usually the shield for the other two cables) absorb most of the noise and electric influence on the cable(the longer the cable is the more noise it will collect - it works as a capasitor) this noise will be eliminate by going to the ground
the + and - cables also absorb electrical noise.
when the signal gets to the end of the cable , if the cable is connected to a preamp that is balanced too, two things will happen - noise absorbed by the ground cable will disappear, and one of the other cables will be phase reversed. this means that the noise collected on the +& - cables is now with a phase reversed and will be canceled. and the original signal, that was phase reverces from the start is now with the same phase on both cables. this will result with a higher signal and less noise. and that is balaced signal. it means higher signal to noise ratio.
got it?

Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•