Wouldn't a Sonogram accomplish this? That shows:
Frequency vertically
Time going sideways
Amplitude is shown by color
Timbre is represented by a series of additional lines above the fundamental frequency, for the partials
If you go to downloads.com (run by CNET magazine), and search for Sonogram, then check the box for 'Free' you get back 12 results, and maybe one or more of these tools would give you what you seek.
Please note that while anything coming from the CNET site is guaranteed virus free, the install process DOES try to sneak in extra software - that's how they pay the bills, I suppose. SO, when installing from software downloaded from their site, it uses an installer that ALMOST ALWAYS has checked boxes for 'yes I would love your unwanted software'. MAKE SURE you remove any such checks or you will have extra stuff isntalled on your computer.
Once you DO remove the check boxes, you are generally good to go, but you STILL should watch the install process, just to make sure there are not similar things during install.
Bob Bone