The scale is extended below D (dukah) by means of a Rast pentachord on G (yakah):
A Rast pentachord on G (nawa) is often used in the ascending part of the scale and a Hijaz tetrachord on D (muhayyar) in the descending part:
The sayr of Maqam Hijaz is as follows. First highlight the Hijaz tetrachord, starting with the note D (dukah) preceded by C (rast), and descend to the Rast pentachord on G (yakah). Next, ascend to the Busalik and Rast pentachords on G (nawa), followed by the upper Busalik tetrachords. In the descending scale, highlight the Busalik and Hijaz tetrachords on D (muhayyar), or just the Hijaz, before working down through the other ajnas. Finally, touch on the note C (rast) before finishing on the tonic D (dukah).
The locations of the notes of Maqam Hijaz on the oud are shown in the diagram below, including the extension to the low Rast pentachord on G (yakah) mentioned above. The full two octaves are presented, with the arrows indicating which notes are modified in the descending part of the scale and the red circles indicating the notes that are substituted for these. A key to all the symbols in the diagram can be found here.
The following diagram shows the optional Rast pentachord on G (nawa) used in the ascending part of the scale:
The final diagram shows the optional Hijaz tetrachord on D (muhayyar) used in the descending part of the scale:
The following recordings include pieces in Maqam Hijaz: