[pHEnomIC]

I am thinking about getting some hdams for my audio-gd compass. What is the difference between the dual and single versions?

 

[TheDuke990]

It doesn't matter because only one version (I assume dual -> Earth dual works well with my FUN) will working properly.
 
At the end of the page you can see which genuine opamp can be replaced by a dual or single OPA -> http://www.audio-gd.com/Pro/diy/OPA/OPAEN.htm