I did a direct comparison (blind test) between this microphone and a R84, both run through SeventhCircle N72 (Neve 1272) and J99 (Twin Servo 990).
I did tests with cello, drums (kit) and steel-string guitar and these are my findings.
The RB500 has a bit stronger signal, snr seems to be very similar between these two mics.
There are definately differences but they are not as big as one might expect. The biggest differences are in highest and lowest end.
On Cello, the R84 seemed to have more clarity in the bottom, RB500 is a bit brighter overall.
I liked the RB500 better on guitar (Furch Jumbo, Spruce), low mids sounded more woody, other than that the high end sounded a bit softer. My guitar has a very complex and brilliant high end so the combination worked very well. Bottom was tighter on R84.
On a drumkit I had similar experiences as above. R84 is a little bit (very subtle) more defined in highs and lows, RB500 a bit brighter but they are similar enough to be used as a stereo-pair without any issues.
Overall this is an amazing ribbon for the money, I would'nt say its not as good as R84, just a bit different. Unprocessed I prefer it over the R84 on my guitar.
Keep in mind that ribbons are very quiet mics so you will need to have a decent preamp or you will be disappointed. Also be careful to not turn on phantom-power or you might kill the ribbon.
/Comae
