Comprehensive analysis of the efficiency-impedance speaker-dynamic?

Through more than ten years many times, I found that consumers buy speakers, regular ask: what is its efficiency? impedance? but few asked: it's brilliance pressure? even in read some magazines of equipment reviews, there are many finds low efficiency loudspeaker represents a high-quality loudspeaker. Audio history does have several famous Horn with low efficiency, such as Rogers of LS-3/5A and AR-3a. Ten years ago I had a small edit Magazine see, domestic audio Division, Mr. Lin Yi sheng, referring to the 3/5a, face was like a God, said: it's the efficiency of its low!, but on that day in Panchiao Chen Xiu (migrated to San Francisco) home, three on the trumpet of the audition, 3/5a play less than two minutes, was another sound heard people a real man to bombard kaima! earlier before, then only the LP has no CD, I bought the rise of the record companies. In the selected record, find the background music funny, how a cold Domingo tenor? nasal so heavy! ask, I discovered that all 」 stuffy Hulu engage 」 3/5a-Rogers at the time of the ghost by rising imports the Horn. I am on 3/5a of the ill-feeling is, I didn't think the world famous BBC-3/5a, turned out to be a 「introduction stuffy 」 hoist. Wait until after the trial, I discovered that BBC DaLine did not play the KEF monomer performance extreme, LS-3/5a benefit only small size, low price, no wonder some people will sell 3/5a swap my DaLine transmission line trumpet. The reason is simple, according to 3/5a bass monomer B-110 specifications, can not be installed in such a small speaker! this point it is necessary to note, in fact, the United Kingdom is not BBC design Horn, but easy to carry, had to be very small horn design, this is no way to compromise. Low efficiency Horn did scenery, but after the CD start becoming more popular, people on low-efficiency Horn holding at the end of the name critics, Ying-l-in-charge of the company Mr. Cao Yong, said high dynamic CD will naturally eliminated low efficiency Horn. Transistor machine w/vacuum machine tile after 20 years, CD system is maturing, but low-efficiency Horn still exist in the market, and low efficiency = high quality concept seems to have not shaken; until recently in the past few years there has been little change only. Vacuum tube and go back to the old factory new factory flock, but the machine after the level of the output power is generally lower than Crystal machine. There is the sound quality is supreme, the non-WE300B no, also don't push-pull and as long as single-ended. 300B do single-ended only around 7-8W output, can push any loudspeaker 7W? of course, someone with a less than 10W of pipe machine level push ATC loudspeaker, it was a voice, but cannot render dynamic ATC. The old era of Altec, JBL, EV and large floor-standing loudspeaker are high efficiency, because their parents honey partners is the machine. So when the machine push Altec A7 「introduction theatre voice 」, momentum is significantly different, who can say that mill-level dynamic after nothing? Watt is Watt, tile is Watts, so the pipe machine 7W almost entirely equal to Crystal-7W-difference is the pipe machine output transformer, the output power is less with the load impedance. So if someone says pipe machine 7W than Crystal machine 7W enough force, that is absurd, because the truth is: Crystal-7W, most of the time than the pipe machine 7W enough, never cheat you. There are two exceptions: one is OTL without output transformer pipe machine-level and the other is the famous LS-3/5a trumpet. Horn's efficiency is expressed using the dB value, but is associated with the impedance, the efficiency is exactly the same, but different impedance of two pairs of speakers, their needs are not the same voltage. Because 8 Ω speakers 1W is input voltage, and 4 2.83V Ω speakers 1W is 2V input voltage. Therefore the same efficiency, impedance of different two pair of speakers connected to the same Crystal after the class will have different representations. Expand the machine output power ︳ 8 Ω ︳ 4 Ω------------------1W-----------------2.83V-------2V 2W-------------------4V-----------2.83V 3W-------------------4.9V---------3.47V 4W--------------------5.66V-------4V 10W------------------8.95V-------6.33V 4 Ω speaker needs voltage although than 8 Ω low, but demand current are relatively large, 4W output, for example, 8 Ω speaker is 0.7A, 4 Ω speaker to eat 1A current, so everyone says low impedance driver harder to push. DB is a DB, its formula for power or voltage and current of the multiples vary speaker efficiency is to power calculation. We now have a great change in impedance of a horn, he said the majority of cases, Crystal machine 7W rubes machine more powerful 7W-key that is current when low impedance. Impedance | Crystal machine power | pipe machine power--------Ω-8--------------7W---------------7W 4 Ω--------------14W--------------7W 2 Ω--------------28W--------------7W as long as the driving current enough, Crystal machine output power increases with loudspeaker impedance decreases, it is not only 7W. But the machine is even output transformer, power does not turn over the loudspeaker impedance transformer. So this is not a Crystal machine 7W rubes of 7W enough force? this is a very simple Ohm's law. 3/5a is inefficient and also high-impedance are constant resistance characteristics of speakers and, therefore, when the speaker impedance Meng to decline, the machine may not force, machine level push after loudspeaker easily from DynaudioA good sound, and therefore intends to take when a speaker, but valve electric current is voltage components to provide current, but swap LS-3/5a won't be the same. 3/5a impedance ｜ Crystal machine power | pipe machine power----------15 Ω--------------3.7W---------------7W 11 Ω--------------5W-----------------7W 8 Ω---------------7W------------------7W 7W of Crystal machine connected to the first generation 3/5a is only the second generation 3.7W 3/5a is 5W; but the machine has been maintaining 7W output. They have 3/5a for high-impedance speakers, pipe machine 7W than Crystal machine 7W came enough force. Therefore crystal machine, high-impedance speakers push less good. But why 3/5a high-impedance are 11 ~ 15 Ω? it uses of KEF T-27A treble monomer and B-110A bass monomers are 8 Ω. This is treacherous, according to the specifications for the design by KEF monomer of the damper and speaker, having surprised, you will find the fundamental LS-3/5a is wrong design! if high impedance coupled with low efficiency, the trumpet and the convergence with tough, 3/5a have this feature. So someone with a big power to push it, but 3/5a and eat great power, the power is too high, it's easier to hit bottom bass-its KEF dynamic bass monomer nothing. Now let's look at the speaker efficiency and expanding machine power relationships than on trumpet is LS-3/5A and Klipsch's Klipschorn, from the following table we can see low efficiency Horn is harder to wait. Klipschorn │ LS-3/5a--------------------104dB/1W---------------------------81dB/1W 107dB/2W---------------------------84dB/2W 110dB/4W---------------------------87dB/4W 113dB/8W---------------------------90dB/8W 116dB/16W--------------------------93dB/16W 119dB/32W--------------------------96dB/32W 122dB/64W--------------------------99dB/64W--? 125dB/128W--?--------------------102dB/128W--? first row 104dB and 81dB is two loudspeaker nominal efficiency, 3/5a's 99dB call?, representing 3/5a cannot withstand 64W continuous input, the bass will hit bottom, 50W continuous input is the maximum value. While the Klipschorn Horn in 1W input, you get the sound pressure of 104dB, LS-3/5a breaking the head is unable to do. As for adding a question mark 125W, that was originally released the Klipschorn maximum 100W continuous work under, so when the continuous input 128W Klipschorn will not. Because of the Klipschorn efficiency up to 104dB, to expand the machine of signal noise ratio is not high enough, that do not have to turn the volume knob, Horn emits annoying hiss and hum. For expansion of residual noise machine and hum, high-efficiency Horn's effectiveness with discerning. 3/What is 5a efficiency? this article assumes that it is as if the memory 81dB is also. But in October 1995, Yearbook, KEF Audio 3/5a of efficiency is 85dB, impedance is still maintain 11 Ω. I was surprised that the trumpet should rise to US $ 1450 pair! God, KEF 3/5a has this value if it has 1450 USD sound, that I do not blush, design of a transmission line on selling DaLine 2400 USD! unfortunately sold to now have all sold out DaLine Horn. No matter what improvement, 3/5a of brilliance, but still not pressure and the Klipschorn basic nominal efficiency. Then calculate 「introduction nominal efficiency to brilliance-」, is approximately 3/5a, 18dB Klipschorn about 21dB. Here are two points that a disclosure is to 300B single ended tube per channel 7W push Klipschorn Horn, its performance will definitely Crystal than 40W× 2 after the class push 3/5a Horn come at ease, hustle. The second point is dependent on common research, is not a high efficiency also represents high dynamic, if that is the case, Mr. Cao Yong Jing prescient. Associate this principle, we elected to use high-efficiency Horn, so after the class output power not easily hundreds of Watts. Of course, 100 dB high-efficiency Horn usually huge size, if it is close to the wall, and not entirely out of the sound field, depth. But to the average family listening to music or watch AV, efficiency seems to be over 90dB. However, low efficiency loudspeaker represents low dynamic? unfortunately, 3/5A and my DaLine is proof. Of course, ATC may disagree, ATC's SCM20 8 Ω/83 d B-efficiency ratio DaLine slightly higher, but its continuous power toleration was 200Wrms, calculate their brilliance pressure was high as 106dB, is by no means LS-3/5a or DaLine generation can be compared. Crystal machine driving high-impedance speakers will reduce power, but there are exceptions, McIntosh is crystal machine, but because of the output transformer, so the output does not change with the load impedanceAnd change. Good audio circle exceptions, no output transformers for vacuum machine, with output output of Crystal machine and only McIntosh. Nominal impedance higher than 8 Ω speakers, these years are very rare. The modern machine output transformer, should only have to have 4 Ω and 8 Ω output two windings. Should use high efficiency, high dynamic speakers connected to the low efficiency of low dynamic speakers, after the level of output power should not be too low, so it stops; but the output power and must not be too high to avoid loudspeaker stand, it is often difficult. 「Cold inefficient low dynamic 」 six words if they cannot understand, as 「introduction inefficient low brilliance-」 eight words is more obvious. Many speakers in the world, but in the spec sheet on clearly identified brilliance without pressure, and by 1%. If it has a maximum continuous power; is suffer is not, it may come from efficiency calculation. For example, the efficiency of a horn 86dB, its continuous bear power 160W, we can easily calculate its brilliance pressure is: 108dB. Use of works of totalizator press a few buttons, 160log× 10 = 22, 86 + 22 = 108 (dB); but this is roughly 22dB Horn. Dynamic range of dynamic range of values expressed in dB, the higher the number the better. Audio equipment performance table has a dynamic range, probably only CD and DVD player to sing; speaker manufacturers almost always does not indicate this specifications to avoid exposing their short. Dynamic range is from lowest to highest changes, from the smallest to the biggest changes, but also by the weakest to strongest, the darkest to lightest. Hi-fi news, the more we show the most weak tone to the strongest. CD singing up dynamic rarely less than 90dB, but speakers seldom high 25dB. This direct comparison of reasonable? of course is not correct, because the dynamic CD sing-up is multiples of voltage range, and the Horn of the dynamic range is the power of computing. We often say that the front-stage 10 times magnification with 20dB of gain, but was converted into 10W power 10dBW instead 20dBW, please see the instructions below. The value dB is the power of computing is: numerical log× 10, voltage, current calculation is: multiples log× 20, 100 times the voltage amplifier is 40dB. If a fore a 14dB gain, it magnifications? use engineering-computer press a few buttons: 14 (dB) ÷ 20 ÷ invlog = 5 (times). If a certain efficiency 86dB Horn's maximum output sound pressure is 105dB, convert Max enduring power is: (105-86) ÷ 10 ÷ invlog = 79.5W. While the 105-86 = 19 (dB), about its dynamic. Distinguish voltage gain of dB dB with the Horn power, you will understand why Hi-End factory opposes expansion of the machine after the level of output power indication become dBW. It is because of 50W, but although 16.9dBW 500W is super power, but also just 26.9dBW. Seems 50W and 500W of output power, the manufacturer may be similar to 「introduction consumers comprehensible 」 do reasons, has been opposed to mark dBW. If the loudspeaker's brilliance pressure-efficiency that is its dynamic range, the dynamic of the General Household Horn? both Avalon Asent, Thiel CS5i, B&W 801, never exceeding 25dB! to area of expertise, the efficiency of RM-8V Rey Audio is 100dB, brilliance pressure is dynamic 130dB, 30dB, 30dB exactly 1000W, i.e. RM-8V affordable 1000W. Japan Audio and sound pressure Rey higher RM-1800, its model has two meanings: one is to use two 18 inch bass monomer, is the speaker height 1800mm. One year 「introduction of Chiapas visitors and birds 」 concert in Osaka, then spent 4 on RM-1800. Reconsideration of the question: If the impedance of the two pairs of loudspeakers and efficiency are the same, with the same expanded machine-driven, will get the same sound pressure?-numbers are typically not be deceptive. Does the same, after many years of practical experience has shown that considerable differences. In response to the measure of efficiency, indoor, may not be able to cover low, medium and high frequency, so also are 95 d B/8 Ω for two on the Horn, its lowest drive power (expanding machine output power), may first, 20W, 50W. But high-efficiency Horn indeed has its advantages, 102dB that means 1W input; if 0.5W input, it also has 99dB! even 0.25W input, also 97dB. At the General House to listen to music, it is difficult to have the opportunity to give the Yin pressure 97dB, 7W output absolute enough. Usually high-efficiency Horn of the somatotypes is relatively large, the common feature is the low-frequency, or say: they cannot be given real bass. Want to test it very simple, with a soundtrack CD is known. The main reason is that not enough low monomer Fs, when they need are: efficient, clean, and not in the low-frequency synthesizer, Elf can sacrifice. If early large-scale high-efficiency Horn, San Huan, Horn stuck to the wall, and only about a metre apart, there should be of sound field and depth are blanked out; basically is often a paste, no sense. Listen to the environment of the background noise to low vision speakers are high efficiency, high pressure, because only in this way can the music most bass to the treble of the change. However, to talk about the dynamic range, it must not miss this important environmental noise. The more quiet listening environment better, but unless you are a professional recording studio, generally after some renovation, its acoustic background noise all over at 35dB-this is the night when the measure, broad daylight situation worse. The height of the background noise and dynamic range are also directly associate, noise, the greater the need for Horn treble pressure to render the weakest of the music. So the listening environment of background noise and equipment of residues, the lower the noise is definitely better, even appreciate 5.1 channel AV, requirements as well. Due to the background noise is high, therefore 「introduction sound 」 to larger, to hear the music for full details. But no problem even if the equipment performanceAlso, the treble pressure, a troubled neighbors will protest, the second is on the ear can cause harm. In the popular dishi can dance hall, to atmosphere, but also to suppress noise of consumers, their PA sound often hype, sound pressure in excess of 120dB, long in the environment, are likely to cause harm to the human ear. Of course, different dance hall at home home audio turn because of a machine, not only the name Canal pop WE-300B back production, JBL, Altec old Horn gradually return to the market. However these Horn loudspeaker is efficient, but the body also is very big, very suitable for the average family place. In addition, there is a doubt: the speaker sound is proportional to its efficiency? recently, several readers mentioned on my United States a medium imported high-efficiency Horn, sound quality is very rough, although very good, but unwilling pawn, can only be used in AV. Small power matching high efficiency in order to avoid wasting energy, and get the right mix, I personally have two great suggestions, but requires global audio sector identity: a, efficiency is lower than 90dB of Horn, manufacturing, sales, import/export, and impedance 8 Ω should be maintained; and second, high output-8 Ω 90W/c h-back level/integrated expand machine, irrespective of the transistor, vacuum tube, it is not allowed to manufacture, sell, import and export (of course, professional equipment is not affected by the above restrictions). If so, then the Dynaudio, VIFA, ETON ... Such famous trumpet plant, will be developed not horn type and shape without a lot of high-efficiency Horn. Because of the expansion of the machine output power, power transformers, filter capacitors ... Can be reduced, so the material cost, weight, size and price can be reduced, this is consumer, the Philharmonic's blessing. You're right?