Home theater speakers are also called AV speakers. They are different and related to high-fidelity (HiFi) speakers. Whether they are AV speakers or HiFi speakers, they should meet the minimum performance requirements of high-fidelity speakers. Speakers are equipment with strong subjective evaluation, so it is difficult for ordinary consumers to grasp when purchasing. The purchasing tips provided in this article focus on practicality and operability, hoping to enhance consumers' immunity to bad equipment. 1. Pay attention to the difference in speaker diaphragm materials: For home theater speakers, there are various forms, including main speakers, center speakers, and surrounds. First of all, the timbre of each channel speaker is required to be unified. The timbre is a comprehensive reflection of the characteristics of the speaker, which makes it difficult for ordinary consumers to effectively grasp it. Generally speaking, the different materials of speaker diaphragms have a significant impact on the sound quality. The materials of the conical diaphragm mainly include ordinary paper cones, wool-mixed cones, surface-sprayed resin cones, PP cones, carbon fiber woven cones and glass fiber cones, etc. Ordinary paper cones are widely used and cheap, and their timbre is basically neutral. The disadvantage is that the mid-to-high range of the frequency response is difficult to handle during frequency division, and it also has limitations in appearance. The wool-infused paper cone has a mellow tone and gives people a sense of warmth. The surface of the paper cone is sprayed with resin material, which has an improved appearance and a slimmer tone. The internal damping of the fiber braided cone is large, the response is flat, and it is easy to make crossover connections, but it is more expensive and will have a hard and tight subjective auditory experience if the bass is not handled well. The PP basin has better mid- and high-frequency transmission and a strong sense of layering, but its use as a bass in home theaters is limited. Dome-shaped diaphragms are generally used for mid- and high-frequency speakers. Materials include hard dome such as aluminum alloy and titanium alloy, soft dome such as silk film, cloth film and nylon film. The hard dome has a wider frequency response, strong sound penetration and good layering. The soft dome has a flat frequency response and a soft tone. Hard dome speakers are generally good at reproducing signals from analog sources, while soft dome speakers are generally good at reproducing signals from digital sources. This is just a relative concept, and we cannot draw a conclusion from it: hard dome speakers are low-end configurations, and soft dome speakers are high-end configurations. If this is true, wouldn't it mean that JBL, which uses titanium membranes extensively, can only produce low-end products? In fact, hard dome speakers are most suitable for three-way speakers, and soft dome speakers are relatively easier to apply. On the other hand, the price of soft dome speakers is relatively low, usually only 1/3 to 1/2 of hard dome speakers, so commercially available speakers mostly use soft dome speakers. However, in home theaters, because the sound is more dynamic and the soft dome speakers are less dynamic, the sound is prone to hairiness at high power, so you should pay special attention to this when purchasing. Consumers have a general understanding of the sound quality of speakers, and can decide which speakers to use based on their own preferences when purchasing. If they are not sure, it is best to make the speaker diaphragm materials of several speakers in the home theater the same. 2. Pay attention to the difference between double bass speakers and passive radiation speakers: Double bass speakers refer to one speaker using two woofers of the same caliber. Double bass speakers have higher low-frequency radiation efficiency and good horizontal directivity, and are more suitable for For home theater use. The passive radiation type speaker is a woofer plus a passive radiator. From the appearance, the two are very similar. Under the same specifications, the cost, price and power tolerance of the double bass speaker are greater than those of the passive radiation type. speakers. The identification method between the two is as follows. When playing sound, press the two bass vibration units respectively. If the sound of both becomes smaller and there is no obvious difference, it should be a double bass speaker. If one bass vibrating unit is suppressed and the sound becomes smaller, and the mid-frequency sound of another bass vibrating unit is suppressed and there is no change, but the bass effect is weakened, then the latter one is passive. 3. Tips for choosing a center speaker: The form of the center speaker is relatively fixed. The center speaker usually uses two 4-inch or 5-inch units, or adds a dome tweeter on top of this. Its main function is to make dialogue clear. Stabilizes the sound image while maintaining continuity and smoothness as it moves. The front of some center speakers is designed to have a certain angle with the bottom. If the center speaker is placed higher or lower, it is more appropriate to use this type of center speaker, which makes it easier for the axial radiation of the speaker to be aimed at the audience. In the normal mode of Dolby Pro Logic, the requirements for the center speaker are lower, and most commercially available center speakers are of this type. In Dolby Pro Logic wideband mode and AC-3 systems, the requirements for the center channel are higher, requiring flat response, low distortion and large dynamics. It is best to use a speaker that is consistent with the main channel for the center speaker, at least The index should also be close to the main channel.

Among the indicators of most center speakers on the market, the lower limit of frequency response is about 80 to 100 Hz, the sensitivity is about 86dB, and the power can withstand 20 to 40W. This type of center speaker is not suitable for broadband mode and AC-3 systems. Many center speakers on the market use ordinary low-power speakers, which have large frequency response unevenness and large distortion. In the wideband mode, the human dialogue changes the tone, the distortion is large, and there is a feeling of hoarseness, and the sound and image are also erratic. For example, the objects in the picture move from left to right, and the sound and image movement makes people feel awkward and unnatural. In addition, in order to create a better sound quality, the impedance of some center speakers is even lower than 4Ω, which can easily damage the amplifier. Therefore, you must be careful when choosing a center speaker. During actual listening, if you feel that the sound is very noisy, the problem is likely to be with the center speaker. You can put the AV amplifier in phantom mode and the effect will become better, which can verify this conclusion. For impedance issues, see Tip 8. 4. Tips for purchasing surround speakers: The function of surround speakers is to increase the surround presence of the sound field and ensure the continuity and smoothness of the transition when the sound image moves forward and backward. Surround speakers are generally small in size. They emphasize a sense of diffusion of the sound field and require the speakers to have a wide directivity, or a flat power response. Many surround speakers on the market have similar problems to the center speaker, so you should pay attention to them when purchasing. Home?THX surround speakers require the use of bipolar speakers. This type of speaker has two radiation directions with an angle of 90° to 180°. The radiation direction does not point to the listener, but uses the reflection of the wall to create a good diffused sound field. The Dolby Pro Logic surround channel has a frequency response range of 100Hz to 7kHz, while the AC-3 surround channel is full frequency range. Therefore, when purchasing surround speakers, it is best to choose wide-band speakers for future upgrades. 5. Sensory selection skills: When buying a speaker, you also need to be able to see it with your eyes, hands, and ears - Eyes: you need to see whether there are any defects in the appearance of the speaker, whether the seams of the decorative leather on the surface are obvious at the edges and corners, and whether the seams on the surface are obvious. Are there any blisters or uneven bumps? Pay attention to the difference between a hard-coated dome tweeter and a plastic diaphragm tweeter with a metal layer on the surface. Domestic plastic diaphragm tweeters have poor performance, have a strong burr sound and are difficult to listen to. There are usually no protrusions on the diaphragm of this type of tweeter. The strong and strong patterns come out. On hand: Weigh the weight of the speaker. Usually the cabinet is heavy, which means the speaker cabinet material is thicker or the speaker uses a larger magnetic circuit. Some speakers have a large diameter but a small magnetic circuit. The bass sounds muddy and the sound is too small, the treble is prominent and harsh, and the weight is relatively light. In addition, some manufacturers add a thicker (some are as thick as 20mm) wooden frame behind or in front of the speaker, and stick a PVC decorative film on the outside to give the illusion that the board is very thick (the actual board thickness may be very thin) ), this type of speaker is generally lighter in weight, just compare it with famous brand speakers of the same specification. On the woofer, spread your fingers evenly over the cone, press it a few times, and check the softness. The softness indicates that the fO of the field speaker is low, and there may be a better low-frequency response. Press the outermost ring of the speaker (mostly rubber edges) a few times and release it quickly. There will be a "pop" sound from the inferior ring. The speaker ring is also made of polyurethane foam. The bass effect is softer and the sensitivity is higher than that of the rubber ring. The surface of the foam ring is rougher than that of the rubber ring, and its service life is shorter than that of the rubber ring. The woofer with cloth-impregnated rubber ring has higher sensitivity, but the distortion is relatively large, especially for the domestic cloth-impregnated rubber ring speaker. The judgment methods mentioned above are only simple judgments and cannot be made absolute. It’s best to listen to it and verify it by listening to it. It would be helpful to use brand-name products as a reference. 6. Find the correct reference configuration: Just like selecting an AV amplifier, it is a very effective way to select representative products for reference. The more representative home theater speakers currently on the market include: Yamaha NS-30X, NS-5X, NS-10M and NS-70 (the above are main speakers), NS-P50 (surround and center), Dushi 5.1a (Full set), Dushi 3.1 (Full set), Coats FB series (Full set), C-LV series (Full set), Panasonic THX series home theater speakers (Full set), JBLMR series, Bosch AM10 (Satellite), Muse AV- 2 series, Xiaoxuanfeng’s MB+BC series, etc. 7. Inspection of the magnetic shielding of the speakers: When the living conditions are limited, the main speakers and center speakers are very close to the TV.

When the stray magnetic field on the surface of the picture tube exceeds 1 Gauss, the color or graphics of the image will change and distort, so magnetic shielding becomes very important. The magnetic field generated by the magnets of the external magnetic speakers is very strong, so the speakers must Features magnetically shielded speakers. To achieve the same performance requirements, the price of magnetically shielded speakers is higher than that of speakers without magnetic shielding. In order to reduce costs, some manufacturers still use external magnetic speakers or speakers with poor magnetic shielding, so magnetic shielding inspection is required. During the inspection, you can put the speaker and the TV close together and set the TV status to a no-signal blue screen state. After a period of time (some speakers cannot see obvious effects in a short period of time for ordinary people), after about ten minutes, The impact will appear. So don't think that you can check the magnetic shielding effect of the speaker by putting it close to the TV). If there is no change in the color (especially at the four corners of the TV picture tube), the magnetic shielding meets the requirements, otherwise There may be no magnetic shielding or the magnetic shielding may not meet the requirements. The magnetic shielding requirements for the center speaker are relatively high, and the requirements for the main speakers can be appropriately lowered. Therefore, the main speakers can also be placed as far away from the TV as the sound field allows for inspection. 8. Beware of counterfeits when buying imported speakers: There are many irregularities in the domestic speaker market, and some manufacturers take advantage of consumers' superstitions about imported speakers to manipulate them. For example, domestic manufacturers register trademarks abroad, produce domestically, fake exports and then enter the market, or outright fake famous brands and openly produce and sell them. The speakers used in this type of speakers are mostly made of domestic parts, with a rough appearance and obvious distortion in the middle and high frequencies. And the portion is too much. There is an identification method for consumers to refer to. Usually, the outside of the folding ring of the woofer will be marked with the model number, while the domestic ones will not be marked or the size will be larger than the imported parts. For example, the imported parts of the 6.5-inch speaker will be marked with the words EC-141, etc., and the domestic ones will be marked with the words EC-141. Speakers are mostly 158, 160, etc., imported 8-inch speakers will be marked with EC-178, etc., and domestic speakers are mostly 200. Therefore, when purchasing imported products, you should choose an agent with a higher reputation. If you find any discrepancies, ask knowledgeable people to help identify them, and be careful not to be deceived.

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