Is there such a thing as a double bass that plays an octave below the usual double basses so as to give an extra rumble at the bottom? - Quora
Kalium Music - Welcome to our NEXT big thing - this is our Rim bass, a 60" electric upright that is the Octobass ( https://en.wikipedia.org/wiki/Octobass ) of our current era. F#-00 is
![Something new from the low register: At long last, Koussevitzky's Double Bass Concerto op. 3 in Urtext | Henle Blog Something new from the low register: At long last, Koussevitzky's Double Bass Concerto op. 3 in Urtext | Henle Blog](https://www.henle.de/blog/de/files/2023/06/Koussewitsky_gemeinfrei_Wiki-scaled.jpg)