Bouzouki in the soundhole. There are also numerous photographs between 1953 and 1959 showing bands in which both vocalists and bouzouki players are using microphones for amplification. By 1960 special bouzouki pickups (such as the German "Ideal") were being produced and permanently mounted in the instruments. Similar pickups are widely used by several Greek artists today and come in active and passive versions. The Greek baglamas () or baglamadaki () is very different from the Turkish bağlama. The treble baglamas is pitched an octave higher (nominally D–A–D), with unison pairs on the four highest strings and an octave pair on the
Shannon capacity of a graph eight neighbors, the eight strings that it can be confused with. A subset of length-two strings forms a code with no possible confusion if and only if it corresponds to an independent set of this graph. The set of code words {"11", "23", "35", "54", "42"} forms one of these independent sets, of maximum size. If "G" is a graph representing the signals and confusable pairs of a channel, then the graph representing the length-two codewords and their confusable pairs is "G" ⊠ "G", where the symbol "⊠" represents the strong product of graphs. This is a graph that has