Cross tuning if played in regular tuning, while the sounded pitch is altered. Cross tuning is commonly used on the fiddle in folk music of Appalachia, the southern United States and Scandinavia. The fiddle may be re-tuned in any number of ways in these musical idioms, but there are two common re-tunings. While the standard tuning for open strings of the violin is GDAE—with the G being the tuning of the lowest-pitched string and the E being the tuning for the highest-pitched string—fiddlers playing tunes in the key of D major sometimes employ a tuning of ADAE. In this tuning the open
Richter-tuned harmonica note downwards in pitch. This allows for every note on the XB-40 to be bent downwards a whole-tone or more, whereas on standard diatonics only certain notes (the higher-pitched in the cell) will bend at all. The other Richter-tuned harmonica of this kind is the Suzuki SUB30 Ultrabend. Where the XB-40 uses valves and a total of 40 reeds, the SUB30 takes a different approach. Each hole of the harmonica houses a third reed, totalling thirty reeds altogether and thus, where the harmonica draws its name. The third reed is dubbed a "sympathetic reed", tuned one tone below the pitch