【 Weak current College 】 exclude multimedia speaker breakdown method

Today, computers are to promote multimedia, intelligence, and the speaker is a multimedia device, an important part, it can be said that the speaker is in addition to the monitor, and our sense of touch is the most direct computer peripherals that have a direct impact on the effectiveness of multimedia computer.
The following multimedia speaker of some of the common troubleshooting methods for members to introduce:
When the speaker does not speak out or only one voice, the first thing you should check the power supply, connection cable is connected, sometimes excessive dust often results in poor contact. If you do not determine whether the sound card, you can replace the audio source (such as connect Walkman) to determine whether the speaker itself. When OK is the speaker's own questions, you should check whether the fuse blew out the speaker voice coil, speaker voice coil wire is whether open-circuit-breakers, feeder, and amplifier is connected properly. When you hear the speaker sound relatively empty, sound field and lax, pay attention to the speaker of the left and right channels are reversed, consider two sets of audio line transpose. If the speaker sound is low, you should check whether the poor quality of the speakers, bass Yang damper phase is reversed. When the speaker has obvious distortion, you can check the bass, 3D, and other regulatory level is too large. In addition, the speaker voice coil skew, speaker core deviation or magnetic gap in the dirt, speaker cone distortion, amplifier feed power too large will cause distortion. When speakers scratchy, generally you should first determine the source of the noise.
1. in the recorder or the radio test speaker is itself a noise, and if so, is the speaker itself can be replaced or repaired speakers. Speaker itself mainly follows the speaker cone rupture, speaker after speaker cracks, plate loose, speakers basin rack is not fixed immediately, the box surface net too loose.
II. the audio swap slots, as far away as possible from other card, such as display card, Modem card, network card, and in particular graphics card, it's the most disruptive, may interfere with including any card for your sound card.
III. on the sound card audio cable pull test, if there is no longer a noise, noise is caused by the audio line, you can change a audio cable, or replace the sound card.
Here are a few examples of maintenance.
Cases of i. shock wave speaker repair.
Trouble phenomenon: a pair of shock wave steering speaker, 30w, rated power as a speaker in the course of a sudden no sound.
Fault analysis processing: first check the appearance of a speaker, did not find anything unusual, power, can hear the buzzing noise, sound the Horn is not burned. Touch the sound box of the back cover, back cover is gradually getting hot. As speaker of the back cover of the amplifier chipset heatsink, the preliminary determination is the speaker's power amplifier ICS is damaged. Cut off the power to open the rear cover, speaker speaker power amplifier, no discovery circuit and capacitor resistance and other components with the exception of signs. Then, in addition to the power amplifier ICS is particularly hot, the bridge is also particularly hot, preliminary judge for the power amplifier ICS greater potential for damage.
Replacement of the bridge, the bridge on the four pin solder with a soldering iron and absorb for removed. Replace the power, after remains found fault; then amplifier manifold heat exchanger. TDA1521 amplifier manifold has nine pin and arrange a dense, so it's more complicated removal. First power amplifier on the screws removed on the chipset, and slowly the pins on the chip solder removal; installation, it is necessary to pay attention to in each tube feet lined Tin-not too much, otherwise easily lead to adjacent pin shorted. In the manifold of screws, special attention should be paid to tighten, manifold and speaker of the back cover, in order to achieve good cooling effect. After you have replaced, troubleshooting manifold blocks.
Cases II. microphone noise cancellation of
Trouble phenomenon: a compatible connected microphone noise occurs, including CPU fans, hard drives, optical drive noise reading disc.
Fault analysis processing: first we analyse the cause of the multimedia computer noise were the following.
1. If you do hear of a hard disk, CD-ROM, and CPU fan noise, it is likely that the motherboard, power supply of filter properties to filter out bad, no hard drive, CD-ROM, and CPU fan of interference signals. Shorten the IDE cable cord and CPU fan power cables can reduce the impact of the device, you can also try another power supply.
2. microphone and sound card's line does not use shielded cable or shielded wire grounding, external high-frequency interference signal from a microphone input string will cause noise into. In this case, unplug the microphone, noise should disappear. If you are connected to the microphone, without the use of shielded cables need to swap the shield line: such as the use of shielded cables, the multimeter check shielded wire outer metal shield is connected with the chassis, exclude ground adversely affected. In addition, from the sound card to the active loudspeaker signal cable should also use shielded cables and grounded.
3. use the "annex" is a "paint" command to open a high-color graphics, cut off a piece, using the mouse quickly drag, such as hear as you drag the sound of the "brush", is due to the built-in motherboards, video cards have the effect of high frequency radiation, caused by the sound card into the expansion slot away from the display card, used aluminium shielding enclosures will sound card shielded and grounded (la search box), you can reduce the impact of high frequency radiation.
4. check the speakers and sound card, sound card ALS007 has two audio output sockets, i.e. the LineOut and SPK, LineOut Jack output audio signal without amplification (high impedance), is used to add active speakers or amplifier; SPK socket output via sound card built-in amplifier of audio signal (low resistance), is used to add passive speaker or speakers. If you mistakenly active speaker input line in the SPK socket, impedance mismatch, audio signals (including noise) after two zoom brings the distortion will produce noise.
If these measures are still not satisfied, you can consider changing sound card try, if you are indeed the soundcard's fault, you should check the sound card on ALS007 chip next to a Electrolytic Capacitor C4, C20, if the two capacitance fall, there is no way to filter out low frequency noise, in itsBoth parallel a 30 ~ 300pF small capacitor, we can filter out high frequency noise.
Case study three .USB speaker cannot play audio CDs.
Trouble phenomenon: a new USB speakers, other are OK, but cannot play audio CDs.
Fault analysis processing: this is because many of the computer's CD-ROM player does not support digital CD audio playback directly from the speakers. Therefore, before using the USB speakers, be sure to read the CD-ROM drive compatibility. Press request packed USB speakers, you can go to "Control Panel", then enter "Multimedia Properties" window "and select the newly installed USB speakers as the preferred audio playback device. In addition, you should select "the CD-ROM device can play digital CD audio" option. If the selection does not appear or appears dimmed, it shows that the CD-ROM drive does not support digital audio.
Cases IV. each boot speakers have noise.
Trouble phenomenon: a computer, use some time after the host each boot-time speakers have noise.
Failure analysis process: first the replacement speaker, if the fault persists, then the fault is not in the speaker itself, replace SRS after noise reduction, everything returned to normal.