What Is The Higher Sensitivity Of Headphones? What Is The Meaning Of Headphone Impedance?
Now many people, many occasions talking about the headset is not easy to push, often looking at the impedance of the headphones, the lower the impedance the more easily push.
This view is not wrong, but also very one-sided, it is easy to misunderstand. Because it is only one of the factors that determines that the headset is good.
In fact the sensitivity of the headset is the key factors that affect the headset is easy to promote, but unfortunately many non-professionals are still in a variety of occasions to just getting started enthusiasts cited errors.
Headset what kind of state is the best?
The best state of the headset should be higher impedance, while the higher sensitivity. High impedance Some of the current source (such as Walkman) draw less, not only save the battery power consumption, but also help to reduce distortion. At the same time, the higher the sensitivity is due to the high impedance caused by the loss of the volume.
Now some players pay attention to the impedance: 16 ohms, and some users believe that the manufacturers of the label (the user can believe who) only matching 16 ohm headphones, limiting the user to select the scope of the headset, in fact, is absolutely unnecessary , As long as the sensitivity of the headphones is higher than some of the impedance can be higher, not only harmless and is beneficial.
In general, the impact of headphones is easy to drive, there are two factors, the first is the sensitivity, the second is the impedance. Even if the impedance is low, the sensitivity is not high, then difficult to drive. Such as Beyerdynamic DT331, impedance of only 40 ohms, but the sensitivity of only 86 dB, it really does not move. The SHURE E5C, the sensitivity of up to 122 dB, although the impedance is 110 ohms, or very good drive. Tell you a little basic common sense generally when the headset sensitivity difference of 3 dB, the driving power will be twice as bad.
Sensitivity is the primary factor in determining whether headphones are easy to drive, and impedance is a secondary factor. To determine whether the headset is easy to drive, the first look at the sensitivity, the second reference impedance. In addition, the portable headphones, earplugs, etc., do not have to bother to study the number of its impedance - originally designed for the Walkman, how could the player do not move it? How could it be high resistance? How could it be? [Headphones have the reasons for noise]
The so-called band without moving, as long as a constant voltage output type of amplifier, driven by the load impedance is not too small, and more than the maximum output current amplifier capacity, then there is no problem, that is, in fact, The greater the impedance of the load, the lower the current output requirements for the amplifier, the amplifier generally work more easily, of course, we have to get the appropriate output power, the load impedance can not be too much, otherwise the useful power is not To a certain output power, the headset to be able to hear the human ear can hear the sound pressure, but also and the sensitivity of the headset, generally expressed in dB / mw, is the headset input 1mw power, can produce how many dB Sound pressure, the strength of the human ear to listen to music is generally about 100dB or so, so if the headphone output power to 10mw, headphone sensitivity at 95dB (headset common value), then the resulting sound pressure level can be To 105dB, almost more appropriate, and 10mw output power for the Walkman if the headset is 100 ohms, then the required output voltage in the 1.4Vrms peak-to-peak, for the final power amplifier, the requirements are not too high, but also acceptable, as long as the power supply voltage can be about 3V, which is no problem for the common DISCMAN, if the headphone sensitivity is too Low, can not produce enough sound pressure level, it can not.