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Thread Starter 

I've been reading a lot, but have a question or two...

 

What is the purpose of a buffer on the output of a virtual ground?

 

Why buffer the ground if you are using buffers on the L/R channels?

 

Here's how I currently understand things...  The source signal enters an op amp and gets essentially copied, using the rail voltages, and multiplied by the gain of the amp.  The maximum current at this stage is limited by the op amp.  To get around this we use a buffer that copies the signal again(unity gain) but is capable of several times more current than the op amp.  This current is supplied by the rails and is determined by the output voltage and headphone impedance. 

 

This is where I get lost.  Is that current used up(converted to motion)?  Does some of it need to be re-absorbed by the virtual ground?  Or, does the virtual ground need to be able to supply half, all, or double the current of the buffers(because of the V/2 split)?


Edited by dbranger94 - 12/29/13 at 5:45pm