1. Impedance of earphone related parameters
Pay attention to the difference between resistance and resistance. In the world of direct current (DC), the effect of objects on the current is called resistance, but in the field of alternating current (AC), in addition to resistance hindering current, capacitance and inductance also hinder current. Flow, this effect is called reactance, and what we call impedance is the sum of resistance and reactance in a vector.
Sensitivity: the sound pressure level that the earphone can emit when the power of 1 milliwatt is input to the earphone (the unit of sound pressure is decibels, the greater the sound pressure, the greater the volume), so generally the higher the sensitivity and the lower the impedance, the easier the earphone is Sound, the easier it is to drive.
Frequency response: The sensitivity value corresponding to the frequency is the frequency response, and the graph is the frequency response curve. The range that human hearing can reach is about 20Hz-20000Hz. The current mature earphone technology has reached this requirement.
2. Sound quality evaluation terms
Range: the range between the highest and lowest notes that an instrument or human voice can reach
Tone: also known as timbre, one of the basic properties of sound, such as erhu and pipa are different timbres
Sound dyeing: The opposite of the natural neutrality of music, that is, the sound has some characteristics that the program does not have. For example, the kind of sound obtained by speaking into a jar is a typical sound dyeing. Sound coloration indicates that some components are added (or reduced) in the reproduced signal, which is obviously a kind of distortion.
Distortion: The output of the device cannot fully reproduce its input, resulting in distortion of the waveform or increase or decrease of signal components.
Dynamic: Allow to record the ratio of the largest information to the smallest information
Transient response: the ability of the equipment to follow the sudden signal in music. The equipment with good transient response should respond immediately as soon as the signal comes, and stop abruptly when the signal stops. (Typical musical instrument: piano)
Signal-to-noise ratio: also known as signal-to-noise ratio, the contrast between the useful components of the signal and the strength of the noise, often expressed in decibels. The higher the signal-to-noise ratio of the device, the less noise it produces.
Low frequency extension: Refers to the lowest frequency that audio equipment can reproduce. It is a scale used to determine how deep a sound system or speakers can dive when reproducing bass. For example, the low frequency of a small subwoofer can extend to 40Hz, while a large subwoofer can dive to 16Hz.