A device for examining a test material via acoustic spectroscopy, comprising a measuring distance which is formed from a reference material and the test material, the acoustic material parameters of the reference material, i.e., the density (ρ R), the sonic transmission speed (c R), the acoustic attenuation coefficient (α R) and the acoustic impedance (Z R), being known for different frequencies, and the length (x R) of the reference material being known, and the length (x M) of the test material being known, and comprising an ultrasonic transmission device for transmitting an ultrasonic transmission signal having an initial amplitude (A 0) through the measuring distance, and comprising a first ultrasonic reception device for receiving the transmitted ultrasonic reception signal after said signal has passed through the measuring distance, and comprising a second ultrasonic reception device for receiving the ultrasonic reception signal reflected on the boundary surface between the test material and the reference material after said signal has twice passed through the reference material or test material, said transmission device being configured for giving ultrasonic transmission signals having different frequencies (f) and the two reception devices (40, 41) being configured for receiving corresponding ultrasonic reception signals (44, 45) having different frequencies, wherein the time of flight (t G) of the allocated transmitted ultrasonic reception signals can be measured, after said signals have passed through the measuring distance, using a first processing device of the device for the ultrasonic transmission signals, and wherein the amplitude (A T) of the allocated transmitted ultrasonic reception signals can be identified, after said signals have passed through the measuring distance, using a second processing device of the device for the ultrasonic transmission signals, and wherein the amplitude (A R) of the allocated ultrasonic reception signals reflected on the boundary surface between the test material and the reference material can be identified, after said signals have twice passed through the reference material or test material, using a third processing device of the device for the ultrasonic transmission signals, and wherein the density (ρ M) can be calculated by the formula the sonic transmission speed (c M) can be calculated by the formula the acoustic attenuation coefficient (α M) can be calculated by the formula and/or the acoustic impedance (Z M) can be calculated by the formula for different frequencies (f) using an evaluation device of the device. and comprising a second ultrasonic reception device for receiving the ultrasonic reception signal reflected on the boundary surface between the test material and the reference material after said signal has twice passed through the reference material or test material, said transmission device being configured for giving ultrasonic transmission signals having different frequencies (f) and the two reception devices (40, 41) being configured for receiving corresponding ultrasonic reception signals (44, 45) having different frequencies, wherein the time of flight (t G) of the allocated transmitted ultrasonic reception signals can be measured, after said signals have passed through the measuring distance, using a first processing device of the device for the ultrasonic transmission signals, and wherein the amplitude (A T) of the allocated transmitted ultrasonic reception signals can be identified, after said signals have passed through the measuring distance, using a second processing device of the device for the ultrasonic transmission signals, and wherein the amplitude (A R) of the allocated ultrasonic reception signals reflected on the boundary surface between the test material and the reference material can be identified, after said signals have twice passed through the reference material or test material, using a third processing device of the device for the ultrasonic transmission signals, and wherein the density (ρ M) can be calculated by the formula the sonic transmission speed (c M) can be calculated by the formula the acoustic attenuation coefficient (α M) can be calculated by the formula and/or the acoustic impedance (Z M) can be calculated by the formula for different frequencies (f) using an evaluation device of the device.