音响线和普通线有什么区别
发布网友
发布时间：2022-04-22 04:41
共1个回答
热心网友
时间：2023-01-28 08:17
转一封国外发烧友的信：
Dear audiophile;
In response to When is good enough, enough, (refering to hi-fi loud speakers) I think you missed the point after reading my epistle ...but then again, maybe that's what I get for assuming readers will "read between the lines".
A speaker is only good enough when it can plicate the original sound it is plicating with such a high level of accuracy that no measurement device, including the human ear/brain, can detect any difference between the original sound and the speaker's plication of the same sound. Of course this is impossible with todays technology. Because of the fact the original sound must, in some manner, be converted to electrons which race down wires at the speed of light, which are resisted and capacitated which will always cause a difference between the original and replicated sound. Therefore, I ask the question, why strive for perfect replication if it is not doable? Further, since it is not currently doable, why should anyone labor over the concern of how accurate or "good" their speakers are, or in this case, when is good, good enough? What matters is if the speaker SATISFIES its owner with the clear understanding that the owner is not hearing anything remotely true to the original sound recorded on the replicating media.
A speaker is not a music reprocer because it cannot accurately reproce the original sound of the music it is attempting to replicate. All a speaker can do is take what is fed into it electronically and proce a "resemblence" of the original sound. Therefore, a speaker should not be called a speaker, it should be called a noise, sound or "musical instrument".
For the record, my first stereo speakers (noise makers) were Bose 901's (back in the 60's when they were the rage). From there I went to ESS Heil airmotion transformer A-1's, then the mighty corner Klipshhorns with center Belle Klipshorn, next came Theater Jensen A-5, then moving on to DQ-10-A's, then to Electrovoice 10-B's, then Martin Logan SL-3's and now a custombuilt $50,000.00 speaker system designed and built by Dennis Dean, Ph.D., an acoustical/audio engineer who fortunetly happens to be my brother.
Now let me tell you something about my home theater. My speakers (musical instruments) feature Scanspeak's slit-cone midrange Revlator drivers and matched silk dome tweeters (their best and most expensive drivers). The upper bass woofers are Daton Titanic III 10-inch drivers and the sub woofers are Daton Titanic III 15-inch woofers. The fs is 19 Hz and in their enclosure go down to 16 Hz at 125 dbs measured at one-meter (they rock the house when they achieve room lock). These speakers are 4-way tower floor standers. The cabinets are 2-inch MDF, braced, properly dampened, and stuffed with a proprietary filler. The weight is in excess of 375 lbs each! The center channel speaker uses the same tweeter and midrange driver as the left right towers. The center channel bass is channeled to the left-right tower woofers via the pre-pro (small speaker setting). The center channel also have two Revelator slit cone mid range drivers and the speaker is laid sideways on its own dedicated stand which places it dead center to the bottom of the movie screen. Cross over and phasing are set to eliminate lobing. The rear surround drivers use linium ribbons and 5-inch hexacone drivers with passive 24 db/Oct cross overs which are housed in a a nonresonate aluminum enclosures. These quasi omnidirectional speakers are ideal for surround speakers. They are mounted 7 feet from the floor on the sides and rear of the theater seating area. They are set on the small speaker setting in the prepro, thus utilize the left and right front main speakers woofers for bass below 80 Hz. They, along with the center channel speaker are crossed over at THX's recommended 80 Hz point. The sub woofer consist of a custom built 450 pound enclosure, tune ported per computer analysis which sports two 18-inch drivers. It works down to 12 cycles (- 3 db point which is the limit to our measurement equipment). Its efficiency is 95 db at 1 meter, 1 watt in put. The drivers are made by Focal (Jm Labs) in France. All speakers are padded to a 90 db output at one meter. All speakers are electronically crossed over and triampliefied with Anthem amplifiers @ 200 watts per speaker (each speaker has its own dedicated amplifier)!
My home theater pre-pro is a RDC-7 Integra Research (latest model with all upgrades). My DVD-CD player is Sony's flagship NS999ES DVD/CD/SACD player. Inter connects are Monster M-1000's wires. Speaker cables are good old fashioned 14 gauge Belden, oxygen free copper wire for the tweeters and midrange drivers and 12 gauge for the woofers and subwoofers (more about that later). My video consist of an 84-inch Stewart Grayhawk electric retractable screen. The overhead-front projector is a Sony Hi-Def LCD Cineza (the only dront projector I have ever viewed that projects a picture which looks good when an end table lamp is turned on in the room). I use Monster's line conditioner powered by a TripLite power converter transformer set up. All AC lines are dedicated 20 amp and grounded with a 3-foot copper stake in the ground. TV reception is DSS satellite. All Inter connects are 2 meters or less in length. Speaker wires are 18-ft. or less. My room is 12-feet high, 18.5 feet wide X 23.5 feet long and semi open to a hall, foyer and dining area (which make wonderful bass traps). This, mathmatically, causes a 34 Hz, 45 Hz and 72 Hz 5 db suckout, a mild 3 db suckout at 52 Hz and a huge 12db boost at 62 Hz and a 4 db boost at 80 Hz. This is corrected with an Audio control 1/6 octave bass equilizer (set with calibrated mic and meter), plus judicious phase adjustment to the sub woofers. The bass frequency measurement while in the main seating area of the room (14-feet from the center of the screen) is + 2db, - 1.5 db from 120 Hz to 18 Hz. The entire system from 20 Hz to 11K Hz. (the limit to my hearing) is + or - 2.5 db @ 4.5 meters from the center speaker, while seated as measured on an HP real time spectrum analyzer. Acoustical treatment consists of hung decorator rugs on the back walls, large back wall book case stuffed with books and nic-nacks, an acoustical fluffed (popcorn) ceiling, a 9 X 12-ft. area rug, and very soft, absorbant, al pleat blinds which may be dropped down on the side walls exactly where the first sound wave launch hits the wall. Speakers are properly placed by comuter and sound meter analysis.
One last thing regarding your comment on replication and judging the ability of
componants to bring you nearest the original sound (my words, not yours). I'm so sorry, but I do not buy into 90% of the hype brought to us audiophiles by the commercial sector of our hobby and the home entertainment instry at large. My brother, an audio engineering whiz kid has proven to me what is real and what is not. Let me rehearse with you an example of how he does this.
We gathered up a 5 of our audio buddies. We took my "old" Martin Logan SL-3 (not a bad speaker for accurate noise making) and hooked them up with Monster 1000 speaker cables (decent cables according to the audio press). We also rigged up 14 gauge, oxygen free Belden stranded copper wire with a simple PVC jacket. Both were 2 meters long. They were connected to an ABX switch box allowing blind fold testing. Volume levels were set at 75 Db at 1000K Hz. A high quality recording of smooth, trio, easy listening jazz was played (Piano, drums, bass). None of us had heard this group or CD before, therefore eliminating biases. The music was played. Of the 5 blind folded, only 2 guessed correctly which was the monster cable. (I was not one of them). This was done 7 times in a row! Keeping us blind folded, my brother switched out the Belden wire (are you ready for this) with simple coat hanger wire! Unknown to me and our 12 audiophile buddies, prior to the ABX blind test, he took apart four coat hangers, reconnectd them and twisted them into a pair of speaker cables. Connections were soldered. He stashed them in a closet within the testing room so we were not privy to what he was up to. This made for a pair of 2 meter cables, the exact length of the other wires. The test was concted. After 5 tests, none could determine which was the Monster 1000 cable or the coat hanger wire. Further, when music was played through the coat hanger wire, we were asked if what we heard sounded good to us. All agreed that what was heard sounded excellent, however, when A-B tests occured, it was impossible to determine which sounded best the majority of the time and which wire was in use. Needless to say, after the blind folds came off and we saw what my brother did, we learned he was right...most of what manufactures have to say about their procts is pure hype. It seems the more they charge, the more hyped it is.
So you see, my friend, that is why I have joined up with this site (audioholics) because their approach to good sound and ecation to acquire good sound and video is based on science, not hype, hypnotics, placebo effects or wishful
thinking.
My best regards;
Dr. Bob Dean
