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“Doctor Vox Ltd. is a company which is dedicated itself to research and development of human voice.”

DoctorVox Therapy System is  a useful approach for voice professionals. Singers can use it to warm-up and cool-down and to find the ‘position’ of the singing voice. By relaxing the unnecessary muscle groups, it increases the consciousness about the vocal mechanism. In the voice clinic, DoctorVox Therapy System is a holistic therapy for various functional and organic voice disorders (muscle tension dysphonias, vocal fold nodules and polyps, habitual and psychogenic dysphonias-aphonias, vocal fold paralysis, presbiphonias, pre, and postoperative phonosurgery etc.)

Dr. Ilter Denizoglu, inventor of doctorvox therapy system


Phonating into glass tubes for therapeutic purposes started as early as 1899 by a German laryngologist Gustav Spiess. The glass tubes, called resonance tubes, were used for rehabilitation of voice disorders and habilitation of Professional voice as well. One end of glass tubes were placed into the water as a therapy approach for velopharyngeal incompetency, then for voice therapy in the 1950s by Antti Sovijarvi, a Finish phonetician.

Marketta Sihvo, invented Lax Vox Tube and simple phonation technique

Finnish Voice Pathologist Marketta Sihvo presented a simple and useful device, a silicone tube which she has named as LaxVox. The LaxVox Tube is 35 cm long and 9-12 mm diameter and dipped into a bottle containing water. Basic physical factors are the artificial elongation of the vocal tract and backpressure by a certain amount of water.
She started to teach LAX VOX-tube exercise by giving workshops at numerous international voice conferences since early 1991. In 2003, in a PEVOC Conference in Graz, a Turkish laryngologist and phoniatrician, Ilter Denizoglu has attended her workshop. He has studied the LAX VOX –tube exercise for two years in his clinic and laboratory. After two years, Sihvo and Denizoglu met again and decided to work together. They have presented the method as LVVT (LaxVox Voice Therapy) in various international conferences until 2014.
In time, Sihvo’s LAXVOX-tube exercise was modified and expanded by Denizoglu into DoctorVox Voice Therapy Method (DVT). DVT is a multi-level, multi-dimensional treatment approach with a well-defined exercise program based on motor learning principles. DVT provides a muscle-specific exercise program for clinical and pedagogical practice combining medical, pedagogical and physical principles.
New devices were additionally devised by Denizoglu (doctorVOX®, pocketVOX®, maskVOX®) for DVT applications. The backpressure was adjusted by an in-built valve. In advance, a unique oral mask was devised by Denizoglu to provide free articulation during laxvoxing. The maskVOX (voice-mask, stimm-maske), was appreciated especially by singers: the magic effect (a term by users) of voice mask astonished many.

a special bottle for pocketvox while manifacturing

Doctor Vox Europe Sp. Z o.o.

Rynek Główny No: 28

31-010 Kraków


NIP: PL6762631127