What I found really interesting is the tuning of this referenced Russian 7 String guitar. By today's standards, that's nothing out the range of a regular 6-stri

What I found really interesting is the tuning of this referenced Russian 7 String guitar. By today's standards, that's nothing out the range of a regular 6-string in the common Drop-D tuning (only a whole step lower than "regular" guitar). Now we're seeing 6-strings tuned to Drop-B (Forth lower) and Drop-A (Fifth lower) in metal genres (And I'm sure even lower).