The name  means “to make noise, hum or buzz.” The gadulka is an integral part of Bulgarian traditional instrumental ensembles, commonly played in the context of dance music.

The resonance chamber is pear shaped similar to a lute  forming a bowl or gourd and it’s often  carved out of a single piece of wood.  The player holds it up right hanging  from the belt or on the lap if sitting.

The gadulka commonly has three (occasionally four) main strings with up to sixteen light-gauge sympathetic resonating stringsunderneath.  Gadulka strings are steel, either plain in the smaller gauges or wound with steel or bronze in the larger ones.

Unlike many other stringed instruments, there is no nut at the top of the strings; the strings are simply stretched between a tuning peg at the top, and the tailpiece at the bottom, passing over the bridge (the 3 played strings) or through holes in the bridge (the sympathetics).  Due to the lack of fingerboard, the strings are not pressed down with the fingers, merely touched with the nails (the highest string) and the pads of the fingers (lower 2 strings).  Bowing is accomplished with an underhand grip.

Though apparently crude and unwieldy, this instrument is capable of great heights of technique and sensitivity in the hands of such masters as Nikola Parov, Peyo Peev, Giorgi Petrov or Mihail Marinov.
Tuning

While various tunings are (and have been) used, the standard tuning for the gadulka is A-E-A for the three melody strings a pitch that gives more opportunities for solo instrumental performances but the tuning differ in different regions; the sympathetics (resonating strings) are tuned chromatically to cover all notes besides A and E

The 3 stringed Gadulka is pitched normally in these different regional ways: Thracia tuning: 1st string – A1 2nd string –E1 3rd string – A, Dobrudja tuning: 1st string – A1 2nd string – A 3rd string – E1  or Lingourie tuning: 1st string – A1 2nd string – E1 3rd string – D1

Gadulka tuning

Example of gadulka tuning with three melody string (black) and 10 resonance strings (in red)

 

Wikipedia

 

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