Transfer from douban:
What is an earphone?
The "pot" of the earphone is actually the pot of the diaphragm ring. The mechanical compliance of the diaphragm ring of the new earphone is poor, which leads to great distortion. After a period of use, the compliance will gradually improve and the distortion will gradually drop to the normal level. For the power amplifier, as long as it is not turned off, it is turned off, but for the earphone, a certain power signal must also be fed in to keep its diaphragm vibrating.
As we all know, new cars and machines have to go through a stage called "running-in" before normal use, so that the internal mechanical devices can fully coordinate and cooperate and enter the best state in advance. Similarly, the pressing unit of the earphone (the speaker in the earphone) is also a mechanical device, which should be a combination of semi-mechanical and semi-electronic, mainly composed of voice coil, diaphragm and positioning ring (metal ring for fixing the diaphragm). The mechanical part belongs to a compliant system, including a diaphragm and a voice coil fixed on the diaphragm. A compliant element can be equivalent to a capacitor in an electronic element. Capacitors store electrical energy, while diaphragms and voice coils store kinetic energy. The flexibility of earphone unit is equal to the parallel value of diaphragm and voice coil, which is the key to determine the sound quality. The materials used in the diaphragm and voice coil are highly flexible materials, and the internal molecular structure is unstable at the initial stage of shaping, so the flexibility is also unstable. When it was first used in a loudspeaker unit, its flexibility was usually small (generally blunt) because its molecular structure was relatively stable. After a long period of exercise, the distance between molecules is far away, the uniformity and compliance of distribution are increased a lot, and the overall compliance of the speaker is also increased a lot. The most important value of the loudspeaker is the lowest resonant frequency, which basically determines the lowest frequency that the loudspeaker can reach, and it depends on the equivalent mass and flexibility of the loudspeaker, because the loudspeaker is a mechanical resonant system, which is equivalent to a resonant circuit on a circuit. The frequency of the resonant circuit depends on the inductance (equivalent mass of the speaker) and the capacitance, and the size of FO and inductance is inversely proportional to the capacitance, so the greater the compliance of the speaker, the lower the F0 of the speaker, and the better the low-frequency dive. The change of compliance leads to the global situation, and all mechanical data of the speaker will change, such as the mechanical quality factor of the speaker. Large compliance means that the mechanical loss increases, so the mechanical quality factor will become lower, which means that the sound sounds softer. Therefore, the new headphones all sound like low-frequency diving is not deep, the volume is small and stiff, the mid-frequency performance is not soft enough, and the high-frequency is burr and too sharp (of course, this is also determined by the quality of the headphones themselves). After cooking for a period of time, the flexibility of the speaker unit will increase and it will be easy to move back and forth, so that the sound will be full and relaxed and the sound quality will be better.
How to cook headphones?
1) How to cook headphones
There is no difference in theory and procedure between the method of cooking headphones and the method of cooking speakers, but you should be more careful when cooking headphones than when cooking speakers. If the pot is not good, it may shorten the service life of the earphone, and even cause permanent physical damage to the earphone, such as careless power overload and excessive amplitude, which will lead to the vibration of the diaphragm. When a friend was cooking Sennheiser headphones, there was a tragic situation that the fixing glue of voice coil lead fell off and hit the diaphragm because of excessive amplitude, which was undoubtedly caused by excessive volume. The diaphragm of the earphone has its service life, just like the speaker of the speaker, but because the amplitude of the diaphragm of the earphone is very small, it is much smaller than the speaker diaphragm, so the service life of the earphone will be longer. If it is used normally, it will be fine for decades. However, if you want to cook headphones quickly and drive them with high power for a long time, the service life of headphones will inevitably be shortened. If the machine is not cooked properly, it is likely to cause irreparable physical damage to the headphones. Therefore, it is very important to cook the headphones to the right volume.
Many friends who have bought new headphones like to listen to the full frequency response with frequency sweep software, but they often feel that the frequency response of new headphones is uneven. Why? This question is easy to explain. If the vibration amplitude of headphones is very consistent, then the sound you hear must be uneven. This is because human ears have different sensitivities to vibrations of different frequencies. It is incorrect to test the frequency response performance of headphones in this way. But also avoid using single-frequency signal to test headphones, which can easily damage headphones, especially high-sensitivity walkman headphones and some monitor headphones products. In the second and third stage of music selection, the music used to cook headphones should be music with little movement. The higher the impedance, the lower the sensitivity of headphones, the longer the cooking time should be, and the overall cooking time of headphones should not be less than 50 hours.
In addition, two problems should be paid attention to when cooking headphones. One is to cook headphones carefully, especially high-gear headphones, and don't use electronic sound. The bass component in electronic music is too strong, which may lead to overload for high-sensitivity headphones and cause irreparable physical harm. In short, slow fire and slow stew are full of flavor. Another point is not to use single-frequency sound signals to test headphones, especially not to use low-frequency signals to measure. First, the human ear is very insensitive to low-frequency signals. For example, if you can hear a signal of 20Hz, the power of the headphones must be overloaded, and some low-power headphones may have been burned out or the voice coil is deformed. 20Hz is a limit. Between listening and listening, some people with bad ears can't hear, so don't call your new headphones at some extreme frequencies.
(b) Make a good sound slowly.
The only universally applicable method for cooking earphones is "step by step". At first, use soft music, let the headphones relax at low volume 100-30 hours, and then cook with ordinary music (except rock and dance) at medium volume 100-200 hours. If you don't listen to harsh high notes at this time, it will become round and natural, the midrange will be warm and kind, and the low frequency will no longer be a chaotic rumble, but full of details, so congratulations, OK, don't be eager for quick success.
Pay attention to two points in the process of cooking: first, you can't work continuously for too long! Because the voice coil has resistance, it will heat up after working for a long time, and it may burn out the voice coil! It's best to stop for a few minutes every two hours and then continue. Second, the volume must not be too high. Earplug diaphragm is a very fragile material. If the volume is high, the stroke of the voice coil will be large, which will lead to the looseness of the voice coil and the deformation and even tearing of the diaphragm.
Headphones are mainly the diaphragm of headphones. At present, the diaphragm thickness of electrostatic headphones is as thin as 135 micron, and the diaphragm of dynamic headphones is only a few microns to a dozen microns (the diameter of our hair is about 60 ~ 90 microns). The diaphragm itself has internal stress in the manufacturing process, and there is assembly stress when the voice coil is bonded and fixed on the frame. The earphone we are talking about is the process of making these stresses disappear gradually, making the diaphragm smooth gradually and making a good sound.
I thought that although the audio equipment was neither a construction machine nor an iron car, there were similarities. Good things should be ground more and cooked slowly to make a good sound! The boiling machine is still divided into five steps: relaxing muscles and dredging collaterals, practicing martial arts, beating and making a debut. Take headphones as an example:
1, relax muscles and activate collaterals-drive the earphone 12 hours at a volume one third of the normal listening intensity (it is best to use 100 ~ 15000 Hz/5s sweep signal);
2. Communication-drive the earphone 12 hours at two-thirds of the normal listening intensity (it is best to use 50 ~ 18000 Hz/3s sweep signal);
3. Practicing martial arts-driving headphones for 72 hours with normal listening intensity (it is best to use 20 ~ 20 ~ 20~20000Hz/2s sweep signal);
4. Jumping-drive the earphone for 24 hours at a volume of four-thirds of the normal listening intensity (it is best to use the sweep signal of 18 ~ 22000 Hz/ 1s);
5, debut-enter the normal use stage.
Step 1: Get a new earphone, you need to cook it to make the diaphragm loose and not tight. As we all know, general earphones are dynamic open coils, and the principle of sound production is that the coils emit magnetic fields of different sizes, thus pushing the diaphragm and using the amplitude of the diaphragm to produce sound. (This principle does not apply to electrostatic headphones) In other words, the final sound is produced by the vibration of the diaphragm, and the headphones we often say also refer to the diaphragm of the earphone.
The new earphone diaphragm is like an unused rubber band, which is not elastic enough and has a short stroke. If we listen to some heavy metals at high volume at this time (for example, our deputy host Glacier just got headphones, which really made him feel bad for many days. An avid metal fan came to listen to some "ferry" cooking machines, and the final result must be broken. The purpose of the first step is to quickly age the mechanical system of the earphone by artificial means.
At this step, there are many ways we can choose the boiler. Let me give you an example:
(1) software method: download a software and cook it with white noise;
You can use the rambler box to make tools.
Download address: 2005/support/sup _ software.php.
(2) Radio receiver method: tune to a place where there is no signal, and its noise is also called white noise;
3. Music machine cooking method: Use some music, and the best machine cooking music is Ferry (other music is ok, as long as the volume is not too loud).
The second step is to make the aged earphone (referring to the aging of the mechanical system in the first step) adapt to the sound of various frequencies as soon as possible and emit better sound from the surface. We generally have a preference for listening to music, either high notes or low notes. Even if we listen to everything, some frequencies are rarely used, which is the key to our beautiful voice. The only way is to use the software, select the signal generator, and then put it on for three hours, cook it when you have time, and cook it for ten or twenty times.
The newly bought headphones have good hearing. But compared with my friend's earplugs of the same model, they are always unsatisfactory. The bass is tight and stiff, the midrange is not soft or full, and the treble part is full of burrs. Why is this happening? Because this new earphone hasn't been cooked yet! (3) Method of testing the tone generator of boiling earphone.
In the past, it was very simple to connect the radio directly, tune to the frequency without the radio, and use the "hissing" sound (pink noise) from the radio to make the headphones work for a long time to achieve the effect of the boiler. But this method is not obvious, so it is better to put on headphones and listen to music directly, which is faster. It is also useful to use a special frequency generator to generate a fixed or scanned frequency and then input it into the earphone. This method has obvious effect and can shorten the time. But most players don't have this kind of equipment. What shall we do? What is the most efficient way to cook headphones? Today, with the rapid development of computers, many enthusiasts have written some programs to process some waveforms and frequencies through computers and output them through sound cards, so as to achieve the effect of some real frequency generators. This is called "virtual instrument". There are many frequency measuring softwares like this. The author uses a software called test tone generator, which is simple, powerful and compact. Let's talk about how to cook headphones with it.
Cooking machines generally use low frequency. So, just set TTG to low frequency. There are two methods, one is to output at a fixed frequency; The second is to use the scanning frequency. The effect is similar. The method of fixing frequency is to input a numerical value in the frequency of constant tone, generally 20 to 50, or you can choose LOOP. The duration is not important. Sine (sine wave) gain is 0 DB, and then you can plug headphones into the sound card to make it work for a long time.
Sweep frequency method is to input the starting frequency with the starting frequency of sweep frequency and the ending frequency with the final frequency. Generally speaking, I think the range from 20HZ to 100HZ is more suitable. Duration is the time required to set a scan, and then other operations are the same as fixed frequency. Many friends have asked me why I only do low frequency. In fact, we can know why from the boiler principle mentioned above.
Pay attention to two points in the process of cooking: first, you can't work continuously for too long! Because the voice coil has resistance, it will heat up after working for a long time, and it may burn out the voice coil! It's best to stop for a few minutes every two hours and then continue. Second, the volume must not be too high. Earplug diaphragm is a very fragile material. If the volume is high, the voice coil will travel long, which will lead to the voice coil loosening, diaphragm deformation and even tearing. Especially the "fragile" earplugs of 888, you should be careful. When adjusting, it is only necessary to adjust the sound waves or air vibration that can be clearly heard. Never turn it too loud and hear the diaphragm vibrate violently. Be careful to protect your headphones.
Finally, I want to emphasize that not all headphones will sound better after cooking, which depends on the quality of the headphones themselves. It is normal for some headphones to have no obvious effect after cooking. The purpose of our cooking machine is to help it quickly pass the aging adjustment period and stabilize the physical characteristics of its components. The vibration system of unheated headphones may be very tight and hard. By cooking, the vibration system can be relaxed and the parameters tend to be stable, so the sound quality will be better. Also, don't think too well about the effect of the cooker. Cooking for a while won't be too effective. The greater the hope, the greater the disappointment. To have a good sound, mainly depends on the sound source and other equipment.