Double bass fifths point out that all of the other orchestral strings are tuned in fifths (violin, viola, and cello), so this puts the bass in the same tuning approach. Fifth tuning provides a bassist with a wider range of pitch than a standard E–A–D–G bass, as it ranges (without an extension) from C to A. Some players who use fifths tuning who play a five-string bass use an additional high string (thus, from lowest to highest: C–G–D–A–E). Some fifth tuning bassists who only have a four string instrument and who are mainly performing soloistic works use the G–D–A–E tuning, thus omitting
Concert pitch D-flat), and are often tuned to match B brass instruments when the two are required to play together. The Stuttgart Conference of 1834 recommended C264 (A440) as the standard pitch based on Scheibler's studies with his Tonometer. For this reason A440 has been referred to as Stuttgart pitch or Scheibler pitch. In 1939, an international conference recommended that the A above middle C be tuned to 440 Hz, now known as "concert pitch". As a technical standard this was taken up by the International Organization for Standardization in 1955 and reaffirmed by them in 1975 as ISO 16. The difference