There is a wide range of techniques and approaches to intonation exercises on the double bass. One of the most used is others use playback software, tuning notes or tracks to train.
Relying on a drone like instrument or synthesizer sound can help to feel the distance between notes. In Carnatic and Hindustani music a drone, tambura (or tanpura in the North India) is used to lay the groundwork1 for the melodic instruments:
Many different tuning exist and the one using the root note the fifth and the octave is widely used. Here is an example of a drone on D (with an 440hz reference tuning). The fifth A is tuned to a pure interval 3:2 ratio.
The following exercise uses a random change of the root note, either D or Eb with an added perfect fifths and octaves and also random lengths where this change will occur.
Beginner students can make use of this exercise by:
Intermediate and advanced students can:
for a more detailed explanation cf. Drones in Indian Music ↩︎