hey guys,
 
Ive seen this on a few music related sites where people have a pretty detailed mapping of their studio gear.  Showing gear, and how it is all wired. Most of these were in color sort of like a Visio diagram.  Does anyone now which or any app out there that is pretty easy to use?
 
Appreciate you all,

Soop
 

Most presentation Software, such as Powerpoint, have this
ability.  I use LibreOffice, which is free, and has total compatibility with
MS Office.

https://www.libreoffice.org/

Look at the comparisons here of 5 different apps (some are FREE!):
https://www.maketecheasier.com/5-best-free-alternatives-to-microsoft-visio/

visio is nice but there are (as noted) freeware too. depending on your need for details - use different colors, indicate flow directions, connection #'s etc. i generally avoid drawing every single line as it can get cluttered fast. 

Thanks everyone!