Samai thaqil (heavy samai) is the slow 10/8 of Ottoman and Arabic classical music, grouped 3+2+2+3: dum – – tek – dum dum tek – –. A dum (conga-lo) opens the first group, a tek (conga-hi) the second, two dums straddle the third and a tek opens the long last group. The second bar adds light ka strokes (rim); the riq (hat) doubles the main strokes.
It is the rhythm of the sama'i form — the instrumental pieces that open or close a classical wasla — and of some muwashshahat. Bass and piano stand in for the ensemble in maqam Bayati on D; its half-flat E is approximated as Eb in 12-TET.
Listen for the dum-dum in the middle of the bar, and the long last group that lets the phrase settle.
Practice: count 1-2-3 1-2 1-2 1-2-3 slowly in eighths before adding the strokes.