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Purpose: Bone-conduction hearing systems (BCHS) transmit sound via mechanical vibration through soft-tissue and skull. The output and the sound quality (THD, Attenuation) of bone-conduction implants and skin-drive hearing systems (that work with low contact force) cannot be directly quantified via conventional measurement devices like artificial mastoid and skull-simulator. Methods: LDV-measurements were performed on 16 participants (age 20.5-29.5 years; 10 female, 6 male) at multiple positions on the head. Pure-tone stimuli (500–4000 Hz) were presented via a Radioear B81 transducer at intensities from −10 to 50 dB HL. Soft-tissue thickness at each position was assessed by ultrasound at low and regular contact-force.Results: Vibration amplitudes exhibited frequency-dependent attenuation with distance from the stimulation site. We measured the highest amplitudes and variability (SD: 7–14 dB) closest to the transducer at the mastoid. Measured amplitude was lower at the concha by 23.2 dB, at the earfront by 38.8 dB, and at the zygomatic arch by 32.3 dB. The lowest variability (SD: 2–6 dB) was measured at the zygomatic arch. Measurements at the concha provided a balance between signal strength and reproducibility. At higher frequencies (1000-4000 Hz) females exhibited 7-10 dB higher vibration amplitudes than males at identical stimulation levels, correlating with thinner soft-tissue. Under regular contact force, tissue thickness decreases by 23-34% with the soft-tissue at the mastoid showing the largest decrease (34%).Conclusion: In-vivo LDV measurements revealed correlations between tissue thickness at the measurement site and vibration amplitude. These findings underscore the importance of tissue properties and coupling conditions in clinical and technical evaluation.