喇叭声音与尺寸大小的关系

喇叭声音与尺寸大小的关系 If you want to have big sound pressure, you need to push more air molecules in more energy per unit time, In the two dimension, the area of the diaphragm for the 15mm horn is about 7.5*7.5*3.14=176mm square, The 20mm is (10*10*3.14=314mm Square), 20mm in diameter, although the horn is only 5mm / 25% larger in size, But the surface area of the diaphragm is 78% larger than when we give the two speakers the same power, The size of the sounds you hear will be very different, because the 20mm speakers can be at the same time, Push more air molecules And the bigger the size, the lower frequency response is usually good, and the sounds the human ear feels are better, Of course, we can also give the trumpet more power, so that it produces higher sound pressure, but is limited to Bearing capacity of 1. diaphragm, 2. heat dissipation capability of loudspeaker, 3. changes in frequency response characteristics after power amplification (the diaphragm needs thickening and the coil becomes heavy... ). Therefore, we have to improve the structure of the material, the horn, as far as possible to small speakers, big sound, But if the size permits, change the trumpet number one, you can immediately improve the voice problem. Factors that affect the size of sound Diaphragm area, amplitude, magnetic field strength, power, impedance, sound cavity size, diaphragm pattern / thickness, opening. Power VS. volume under the same conditions, power increases, does not mean that the volume will increase synchronously. Because of changes in diaphragm and voice coil, at the same input signal, sometimes the volume will be smaller. Size VS. the bigger the volume, the more air it can vibrate at the same time, so the volume will be bigger. The thicker the horn, it usually means that there is a larger amplitude, and the sound will be bigger. Sound quality small speakers basically do not discuss the sound quality, but try to make the volume higher. The power of the matched amplifying line is better than the horn, and the rated power will be better. Generally speaking, the size of the sound cavity in the consumer products has the problem that the sound cavity is not big enough. Only the empty places can be found as much as possible, and the volume of the sound cavity can be increased. The opening rate must be at least 1/8 of the diaphragm area, and the front and back sound fields of the hermetic horn should be completely spaced so as not to cancel each other; Because of the sound produced by the loudspeaker, the shock absorber can also generate vibration, and the best buffer material is provided between the shell and the case, so as to avoid generating noise. Fixed speakers are usually fixed on the case, the need to pay attention to reliability, especially iron or larger size, so as not to fall off test. In the premise of all conditions, if the driving circuit provides for voltage, the sound of the horn is relatively large, but if the voltage driving circuit can provide is the same, the change on the rated power of the greater horn, there will be the so-called push in sound but will be smaller. For example, only a 8ohm 1W power line, want more loudly and change with the 2W horn, but quietly, because with the increase of power design, membrane loudspeaker needs thickened, voice coil may also need a thick line, more coarse line impedance will decrease, but more around a little longer the quality of the voice coil is more important, these changes will make the horn efficiency variation, or quietly we say, if we change with the power to bear smaller or a little low impedance loudspeaker, It's possible to speak a little louder, but be careful that the speakers don't break or even burn down. The causes of broken tone / abnormal sound in loudspeakers are analyzed from the reasons of users' use: The horn is belongs to the passive components, what the sound will be issued is determined by the driving circuit of the horn, the horn given the correct power waveform is the most basic requirements, the power is too large will result in excessive diaphragm amplitude, there will be a slight distortion, the worst case diaphragm will hit the mechanism or magnet that resulted in a broken voice; The basic waveform of the drive horn is string wave, and if given to other waveforms such as Fang Bo, the horn will become less efficient and easy to heat, and may also produce a broken sound; The speaker design product of the institution will also affect the horn sound, the response curve of appropriate speakers can improve the horn, trumpet sound hole has the best opening rate of more than 1/8, the space between the left diaphragm vibration and the casing and the diaphragm, in order to avoid the sound when hit by shell and noise. The size of micro speakers: size, has a decisive effect on the volume, diameter is 5mm, the membrane area may have sent half (15-20mm), so the volume is very different. In addition, the thicker the horn, because there is a large space to be vibration, usually with a large magnet so, there is more power to promote the air, have a greater voice. Power: mainly refers to the power of the horn can withstand, and the size of the volume and there is no absolute relationship, the greater the power required by the diaphragm horn, more thick, more rough voice coil, to withstand the big power, so the efficiency will be reduced (voice), the coordination mechanism design, try to use a larger size, can choose and enlarge the power output matching circuit, make the greatest sound. Impedance: impedance is high, the more power, but the volume will be smaller, and can withstand the power will become smaller, because the thin line (with the necessary power smaller), or more around the circle (quality, efficiency). Diaphragm pattern: voice horn diaphragm can be used with concentric pattern, usually in the 5-6KHz before the sound pressure is relatively large, but after 6KHz, will fall quickly. But the diaphragm radial radiate pattern overall frequency response is lower than the average, in other conditions are the same, under the assumption of 6KHz before the volume will be lower than the concentric circle pattern. Vibration film material: 50mm below Mylar mostly used as vibration film material, because easy processing, waterproof, low cost, but less heat, the sound quality is more rigid. Although any speaker has its strengths and weaknesses, especially on a limited budget, cheap speakers are not easy to get perfect results, but whether the speaker at any price and level, have certain reference standards or reference direction. 1. test low frequency quality The low frequencies produced by poor speakers can be "deaf", but completely bloated, loose, lacking in layering and strong. The low frequency should be clean and crisp, clear, not sloppy, the ghost does not spread like, even though a variety of musical instruments such as the size of the low frequency bass guitar and Piano drums, bass, can easily distinguish. So don't be easily deceived by the low frequency sense of quantity, inferior frequency is not as natural as the sound of clean. Two Test the voice of the intermediate frequency Voice is the most commonly heard voice, the quality is not difficult to detect, pay attention to whether or not the voice of the unusual nasal sound or the sense of being closed mouth sounds. Some speakers' box noise also greatly interferes with the intermediate frequency, making the band sound blurry. If colourations compared to other frequency noise pollution is more serious, because the most audible sound frequency, or frequency of music are concentrated in the intermediate frequency range, which is almost all kinds of music, will become the obstacle to the replay. 3. test high frequency flexibility Poor high frequency is the sharp insertion of the ear to hear the head splitting; in extreme cases the violin or soprano bel canto becomes the sharp noise of the brakes. Similarly, different musical instruments in high notes produce different textures, and good treble can distinguish them. The high frequency of the first and the second can even distinguish between the two different wooden sounds produced by the two different years. The most easy to grasp the key is good, the treble is not back to people listen and intimidating, pores erect, would not be heard the more tired, but it is soft and tough and elastic, smooth and high level to the highest point can easily hear no sound (of course not to hand out of tune song the recording for reference) 4. test high volume and tone field images Some speakers were stable at low volumes, but the volume index will be promoted to a certain distortion, or "shot", the emergence of various non music signal recording, (of course, but with 12 points for the test volume safety standards). Specifically, if orchestral music is one of the most desirable, it must pass through this pass. Speakers of standard to a certain extent do sound from the box, create a sound field and clear image, showing different musical point position and texture, there is sufficient diffusion and growth, broad and high degree but audio space. Piano and tail should be clearly heard, and in large volume and "bursting" without distortion, vocal and instrumental sound is not entangled. High quality replay can show rich musical sense and air feeling, and the jumping ability of notes, like the cloud and mist, see the blue sky, showing the whole meticulous and orderly audio-visual. And more directly, it won't make you tired of hearing. Physical characteristics of sound Sound (Sound): a pressure wave generated by shock in an elastic medium (Elastic, Medium) Wave (Wave): the manner in which energy is transmitted from one point to another Wavelength (Wavelength): the length occupied by a cycle in space Frequency (Frequency): the number of cycles completed in a second (Cycle). The unit is Hz. Cycle (Period): the time required to complete a cycle (Cycle) Wave velocity (Velocity): velocity of wave motion Wave speed = wavelength * frequency The speed of sound is related to the medium Density (Density): usually in the more dense medium, sonic sooner. Elastic (Elasticity): usually in the higher elastic medium, the sooner the speed of sound. Energy (Energy): in the air, the higher the temperature, the faster the speed, the formula is as follows: Vs = 331 m/s + 0.6T So at 20 degrees C, the speed of sound is 331+20*0.6=343 m/sec. Amplitude (Amplitude): the measurement of the displacement of a molecule in a medium, The volume used to indicate sound RMS (Root Mean Square) root mean square value is 0.707 times the maximum amplitude Average (Average): 0.637 times the maximum amplitude Resonate Frequency: the natural frequency of an object's vibration Field (Free): no barrier, no sound field / space for reflected sound waves With the increasing number of private cars, people are driving more and more cars are more and more like modern people, a mobile home. A boosting or soothing music can change the occupants of the mood, while bad sound effect will only make the mood worse. Car audio and sound source is divided into two parts Car audio is basically divided into two parts and sound source. Among them, the audio part refers to the host, including CD host, VCD host, DVD host, host with MP3 function and so on. Many well-known brands host, product categories to billion. Or recognized more reliable quality for Japanese products, including SONY, Matsushita and other products are more popular products, the sound quality is stable, comfortable, but the personality components are less; but the date is in the vanguard, ALPINE, clarion, Denon, the other brands of host will show more personality and professional point. Sound, including power amplifier and loudspeaker. The sound reduction performance of the loudspeaker is different from region to area. Such as American style, music is full of metal taste, relatively strong, especially for young people; the British style, tone relatively gentle, listen to the nostalgic songs more comfortable, suitable for different age groups; Nordic style, suitable for listening to quiet serenade. The installation is the largest British style, pure sound, strong sense of hierarchy, but not boring, but the Nordic style seemed to be more suitable for indoor appreciation, because of interference on the road is bumpy noise, only the time to carefully taste parking. Asian products can be played evenly, but in general, the personality is lacking, and there is no such thing as an outstanding addition to the price. The decisive factor of sound The voice of big and small, have high is low, car audio sound judgment mainly from four aspects of tone, timbre, volume and tone to. Pitch is the element that expresses the frequency of sound, mainly related to the frequency of sound source vibration per second. It is the subjective evaluation scale of the human ear's pitch. The volume is used to reflect the intensity or loudness of sound, indicating the intensity of sound. Quality is a factor characterizing sound characteristics. The music used in the voice, the envelope of harmonic composition and waveform, including transient and the end of the music start, determine the musical features, called timbre, also the timbre and tone called timbre. - buy tips The output power of the amplifier is greater than the power of the horn The output power of the amplifier must be greater than the output power of the horn, otherwise it will not only affect the sound effect, but also speed up the damage to the power amplifier. Such as the choice of the speaker impedance amplifier output impedance ratio is high, will affect the output of the power amplifier; and when the low impedance loudspeaker, such as less than 4 ohm, output power of the power amplifier and the rated use does not match the distortion of this case will increase. If the impedance of the horn meets the requirements, Rated power and rated power amplifier is slightly smaller than, the distortion is relatively small, the horn sound quality is good, in the selection of speakers generally require a rated power amplifier is 2 times larger than the horn, the actual bearing power horn 2-3 times than its rated power output. Reserved upgrade space In the purchase of installing a machine, in order to expand the future upgrade installation of power amplifier and subwoofer speakers, in order to achieve better sound effects, such as choice of high voltage multi group before the stage output (audio signal output) of the host. The sound signal is converted to electrical signals or convert electrical signals into sound signal transducing devices. Including speakers, headset, microphone cartridge, etc.. Characteristic parameter: Rated impedance: the impedance value specified by the manufacturer's product standards. The maximum power can be obtained on the impedance. Rated power: the maximum power that a loudspeaker can work for a long time. It is replaced by the following power in the world. 1 the maximum noise power within the operating frequency band specified by the manufacturer is fed to the weighted white noise signal which can withstand 100 hours without permanent damage to the power. 2 long term maximum power, within the operating frequency band specified by the manufacturer, is fed to the white noise signal which has been weighted. The loudspeaker shall withstand 1 minutes and repeat 10 times intervals for 2 minutes without permanent damage. 3 short term maximum power: within the working frequency band specified by the manufacturer, the white noise signal, which is weighted by the manufacturer, is fed to the receiver for 1 seconds and repeated 60 times at intervals of 1 minutes without permanent damage. Effective frequency range: take an octave at the maximum of the sound pressure curve. On this basis, 10dB is reduced to parallel lines. The two intersection points of the parallel line and the sound pressure curve are the effective frequency range. Characteristic sensitivity: in the free field conditions, the sound pressure measured at 1 meters on the reference axis is fed into the 1 watts pink noise signal in a given frequency range. =20log characteristic sensitivity (kPa) / reference sound pressure (20*10 (-6 side) PA) Resonant frequency: the maximum value of the first impedance that occurs when the impedance modulus of the loudspeaker varies with frequency. It is the lower limit of the effective frequency range of the power amplifier. Harmonic distortion: he is the distortion caused by the nonlinear amplitude of the vibration system. When fed into a positive rotation signal, it also appears 2 times and 3 times in addition to the fundamental wave... Yu Jibo frequency signals, these signals are called harmonics, and the harmonic distortion is expressed as the ratio of the root mean square of the sum of sound pressure at harmonic content to the mean square of the output signal.