Erhu Basic Theory

Erhu, a Chinese violin, consists of a wooden block base and a stem. You play with the base resting on you left thigh next to your groin and with your left hand curved around the stem. It has two strings. The upper and thicker string is the inner string and the other is the outer string. You play the instrument by pulling or pushing the bow, like a violin. The bow is locked between the inner and outer strings.

The inner and outer strings are normally tuned to a perfect fifth; i.e. the inner string is tunned to D and the outer string is tunned to A. Once tunned, the instrument can be used to played in any keys without adjustment.

The first three keys are sufficient for beginners. These keys are: D Major (or Do - Soh), G Major (or Soh - Re) and F Major (or Lah - Me).
First Fingering Positions

For Do-Soh key, with open strings (i.e. not pressed) the inner string is Do and the outer string is Soh. Then use the first finger for Re; second for Me; third for Far. The first finger on the outer string is Lah; second is Te; third is Do (upper); and forth is Re (upper).

For Soh - Re key, the open strings are Soh (Lower) and Re. On the inner string, use the first finger for Lah (Lower), second for Te (Lower); third for Do and forth for Re. On the outer string, use the first finger for Me and second finger for Far; third finger for Soh and forth finger for Lah.

For Lah-Me key, the open strings are Lah (Lower)and Me. Use the first finger on the inner string for Te (Lower) and Do; second for Re; third for Me. Use the first finger on the outer string for Far and Soh, second for Lah; Third for Te; and forth for Do. The open outer string sounds better for Me, so use it where convenient.

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Second Fingering Positions

Erhu has five fingering positions. However, the first two positions are sufficient for beginners. Why we need other fingering positions ? There are three main reasons:
To satisfy high and low notes: The first position allows for 8 notes. When we come across music that requires outside these eight notes, we need to use the second and other positions.
To express the feelings: We can sometime provide more expression of feeling by changing positions.
To facilitate sliding: Erhu techniques include up slide and down slide. Sliding is an important technique in Erhu performance. We need to change the position to achieve sliding outcomes.

Erhu 2nd Fingering Tables