I've seen some people use sort of a "backstop" baffle almost directly behind their mic. Do you think this would make a significant difference?
I do. Think of it this way: That mic has a cardiod pattern, so it is least sensitive behind the mic where your egg-crate is, and most sensitive in front where your DIY panels are. But there is also a lot of hard, reflective surface behind you between those panels . So it would follow that it is hearing all those reverberations off the walls behind you. I turned my whole setup around and now I have my best, thickest absorption panels right behind me ,
and I sit pretty close to the wall to try and minimize these reflections.
A quick aside, and this is relevant - I promise - my daughter is a huge One Direction fan, and watches Youtube videos about them pretty much constantly. I totally rearranged my setup, after making her rewind this video to see how they were recording vocals in a hotel room look how much absorption is behind them instead of behind the mic.
https://www.youtube.com/watch?v=3ycHifZqIGM&t;=19
Note that there is lots of padding behind them, and a SE Electronics Reflexion Filter
My policy is this: Experiment! Give it a try. Rearrange stuff, then record, then listen critically, if it got better then there is your new baseline setup to try again. I’ve been through probably 4 or 5 configurations before I got to where I am now (and I’m still thinking of other ways to rearrange!)
Finally. Listen critically, see if you can hear what is reverberating. I found that when I was doing really loud parts the metal covers on my baseboard heat radiators would reverberate!