Electroacoustic bouzouki with perforated vessel, for exercise as well as for concerts having a neck (1) which reaches until tailpiece (2), head (3), tuning keys for fastening strings (4), electromagnet (5) and bridge (6) on the front part (7) over which the strings pass (4), preamplifier (9) and amplifier (10) in its body, output (12), electric signal and battery (16), bearing, a rear part called vessel (13). The vessel carries on its surface at least one user-defined opening of any shape and is mounted on the front part (7) of the body by gluing or screwing. The best use of the electroacoustic bouzouki with perforated vessel takes place when the number of openings ranges from 2 to 6.

A universal capo for use with a variety of stringed instruments and with a variety of gauged strings has an upper rigid arm extending longitudinally. A core block made from an elastomer with a first durometer is mounted to the rigid arm. A wrap layer made from an elastomer with a second durometer cradles the core block on the bottom and lateral sides and can extend over the top of the rigid arm. The second durometer hardness is at least 1.5 times the first durometer hardness and the core and wrap have thicknesses collectively contributing to a substantially even pressure on strings of varying gauges to effectively clamp the strings to the neck of an instrument without application of undue pressure.

A universal capo for use with a variety of stringed instruments and with a variety of gauged strings has an upper rigid arm extending longitudinally. A core block made from an elastomer with a first durometer is mounted to the rigid arm. A wrap layer made from an elastomer with a second durometer cradles the core block on the bottom and lateral sides and can extend over the top of the rigid arm. The second durometer hardness is at least 1.5 times the first durometer hardness and the core and wrap have thicknesses collectively contributing to a substantially even pressure on strings of varying gauges to effectively clamp the strings to the neck of an instrument without application of undue pressure.