A customer who has come up with some weird requests has come up with another....A 6 string , tuned similar to a violin...He'd like the low note to be a F...( Below a bass guitar E )...To a high E...( as on a regular guitar )...I know I can accommodate the low string with a baritone or short scale bass scale length , but , how about the high E ?....It will be an electric , and he has no real problem with some floppiness on the low end....I converted a Yamaha acoustic to a 10 string bass , with the low note a B below the normal low E string , with the 5 notes all octaved for him , at his request..Made a custom , intonated bridge , and that was 7 years ago , and it's still holding up !...Thoughts ?
Maestro Alex Gregory has invested a long time of research into fifths tuning (pentasystem). He settled on 5 strings, tough, but check out his instruments for more inspiration.
Also, he found out that he could compensate the different string tension by varying their break angle across the nut. His patents are here: