Industry consulting
How to Diagnose and Handle Moving Loop Wheat
The main faults of coil-moving wheat are disconnection, which is at the plug of the microphone, disconnection of the microphone lead itself, and disconnection at the voice coil. Disconnected faults can be found in the omnimeter ohm file. The way to deal with the break line fault is to re-weld the break line. When the break line breaks at the voice coil connection, it is difficult to weld, sometimes even unable to repair.
Microphone Classification
Microphones are usually classified according to how they convert energy. Here we still divide the microphones into coil-moving microphones and capacitive microphones according to the most common classification of studio microphones.
A microphone that produces electrical signals from conductors moving in a magnetic field. It is the vibration film that drives the coil to vibrate so that the coil in the magnetic field can induce a voltage. Features: Strong structure, stable performance, durable, low price; The frequency characteristics are good, and the curve of amplitude-frequency characteristics is flat in the frequency range of 50-15000Hz. Good pointing; No DC working voltage required, easy to use, low noise.
Capacitive microphone
The diaphragm of such microphones is an electrode of the capacitor. When the diaphragm vibrates, the distance between the diaphragm and the fixed back plate follows.
The change produces a variable capacitance, which together with the preamplifier that the microphone itself carries, produces a signal voltage. Features: Good frequency characteristics, flat amplitude-frequency characteristics curve in the audio range, which is better than coil microphone; No directionality; High sensitivity, low noise, soft tone; Large output signal level, small distortion and good transient response performance are advantages that can not be achieved by coiling microphone. The working characteristics are not stable enough, the sensitivity of low frequency band decreases with the increase of usage time, and the life is short. It is inconvenient to use DC power supply when working.
There is a preamplifier in a capacitive microphone, of course there must be a power supply. Due to volume, this power supply is usually placed outside the microphone. In addition to the polarized voltage supplied to the capacitor film, the necessary voltage is supplied to the tube or transistor of the preamplifier. We call it phantom power supply. Because of this preamplifier, capacitive microphones are relatively sensitive, and some of the necessary accessories for use are: shock absorber (usually given with the microphone), windshield, blowout preventer, and high-quality microphone holder. A blowout shield is essential for ultra close recording.
Characteristic of coil wheat
1. Direction of the moving circle wheat
Generally divided into heart, super-heart, 8-shaped, gun, omni-directional, and so on.
You can find a microphone to try out what these pointers are really about. As shown in the figure, the arrow is pointing in the direction in front of the microphone, and the dashed line is the approximate range within which pickup will not be sensitive. If you have the right conditions, it is advisable to find a multi-pointing microphone and try it out, so you can see what the pointing means.
2. Impedance of the microphone
Professional studios should use low impedance microphones, which can reduce signal attenuation because long cables may be needed to connect them.
3. Balanced Linearity
The balance line consists of two wires and a shielding line. There is only one conductor in the unbalanced line, and the shielded line is used instead of the second one.
The advantage of a balanced line is that the two wires of the line pick up unwanted noise signals with equal intensity, so they can cancel each other out. The non-balance line transmits the noise signal to the lower level of the line.
If the audio signal is strong or the unbalanced line is short, noise may not be heard. But the microphone wires are usually very long. Just think about it, we pull the wires out of the studio and go through the wall of the sound box to the tuning and recording system in the control room. So we need to use the balancing cable and use the balancing plug accordingly: XLR, commonly known as Canon's head or Mother's head; Or a big three-core TRS.
Microphone Classification
Microphones are usually classified according to how they convert energy. Here we still divide the microphones into coil-moving microphones and capacitive microphones according to the most common classification of studio microphones.
A microphone that produces electrical signals from conductors moving in a magnetic field. It is the vibration film that drives the coil to vibrate so that the coil in the magnetic field can induce a voltage. Features: Strong structure, stable performance, durable, low price; The frequency characteristics are good, and the curve of amplitude-frequency characteristics is flat in the frequency range of 50-15000Hz. Good pointing; No DC working voltage required, easy to use, low noise.
Capacitive microphone
The diaphragm of such microphones is an electrode of the capacitor. When the diaphragm vibrates, the distance between the diaphragm and the fixed back plate follows.
The change produces a variable capacitance, which together with the preamplifier that the microphone itself carries, produces a signal voltage. Features: Good frequency characteristics, flat amplitude-frequency characteristics curve in the audio range, which is better than coil microphone; No directionality; High sensitivity, low noise, soft tone; Large output signal level, small distortion and good transient response performance are advantages that can not be achieved by coiling microphone. The working characteristics are not stable enough, the sensitivity of low frequency band decreases with the increase of usage time, and the life is short. It is inconvenient to use DC power supply when working.
There is a preamplifier in a capacitive microphone, of course there must be a power supply. Due to volume, this power supply is usually placed outside the microphone. In addition to the polarized voltage supplied to the capacitor film, the necessary voltage is supplied to the tube or transistor of the preamplifier. We call it phantom power supply. Because of this preamplifier, capacitive microphones are relatively sensitive, and some of the necessary accessories for use are: shock absorber (usually given with the microphone), windshield, blowout preventer, and high-quality microphone holder. A blowout shield is essential for ultra close recording.
Characteristic of coil wheat
1. Direction of the moving circle wheat
Generally divided into heart, super-heart, 8-shaped, gun, omni-directional, and so on.
You can find a microphone to try out what these pointers are really about. As shown in the figure, the arrow is pointing in the direction in front of the microphone, and the dashed line is the approximate range within which pickup will not be sensitive. If you have the right conditions, it is advisable to find a multi-pointing microphone and try it out, so you can see what the pointing means.
2. Impedance of the microphone
Professional studios should use low impedance microphones, which can reduce signal attenuation because long cables may be needed to connect them.
3. Balanced Linearity
The balance line consists of two wires and a shielding line. There is only one conductor in the unbalanced line, and the shielded line is used instead of the second one.
The advantage of a balanced line is that the two wires of the line pick up unwanted noise signals with equal intensity, so they can cancel each other out. The non-balance line transmits the noise signal to the lower level of the line.
If the audio signal is strong or the unbalanced line is short, noise may not be heard. But the microphone wires are usually very long. Just think about it, we pull the wires out of the studio and go through the wall of the sound box to the tuning and recording system in the control room. So we need to use the balancing cable and use the balancing plug accordingly: XLR, commonly known as Canon's head or Mother's head; Or a big three-core TRS.
