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  • 热度 5
    2015-6-3 22:07
    913 次阅读|
    2 个评论
    1. 我的工作   做了很多年的IC销售,不禁熟视无睹起来。订货、进货、库存、销售、回款;pull in, pull out,订单取消、客户拖款、坏账 …… ,林林总总,不一而足。   不过,有些工作值得重新再来。不需订货、没有库存,当然也没有pull in 、pull out,许多问题也就迎刃而解。   电视机、移动音响等产品风起云涌,时尚的潮流是:轻、薄、小。随之而来的问题就是音响效果普遍较差,声音干涩单薄、声场狭窄、人声含糊,最糟糕的是低音几乎没有。简单的道理是同等档次的喇叭越大、腔体越大,音质越好;反之就越差。   这个矛盾怎样解决?   从事音频电声行业的朋友一定脱口而出,用音效!哈哈,好回答!不过什么是音效呢?我向我服务的美国公司请教Sound Effect是什么?他认认真真地举例子告诉我:比如:电影中那乒乒乓乓的*声、轰隆隆的雷声,这制造的效果就是Sound Effect。   美国人说:我们提供的是Audio Enhancement,是帮助提高声音质量的玩意。这样,我看这个技术应该称为:音质提升。和Sound Effect有些南辕北辙了。不过,在和我客户的接触交流中,大家还是习惯用“音效”,我能明白他们的意思,也就入乡随俗了,呵呵。   说起翻译上的差异,不是身临其境,无法想象!我的老师从来没有教过我Restroom是什么?我望文生义是休息室,机场、商场等公共场所随处可见。而我们熟悉的WC、Toilet却遍寻不到。我问美国朋友WC在哪里?他们云里雾里!他们会用Man’s room或者Lady’s room,也可以猜出Washing room或者Toilet但是 WC,除非跑过江湖的美国人,他们确实不知道,真的不知道!     
  • 热度 5
    2015-3-27 18:25
    954 次阅读|
    0 个评论
    I never met Richard Feynman but I am glad to say that I played a small role in preserving what he had to say, especially stories about events in his past. I first encountered Feynman’s physics books when I was in college in the late ‘60s. A picture in the forward of the book showed Feynman playing bongo drums. What kind of a physicist could this be, I wondered to myself. As decades passed, I encountered people who had taken a course from Feynman, usually at CalTech, including physics professor Julian Noble. Walter Thorson, a theoretical chemist who went through school the CalTech-MIT route and taught for many years at the U. of Alberta in Edmonton, is another. In one of our roving discussions, I recall Walter telling me about Feynman’s teaching style and his ability to do contour integrals in the most non-obvious ways. It was hard for Feynman, as brilliant as he was, to teach minds of ordinary brilliance. The former Feynman student who stands out to me the most was a friend of mine and fellow homesteader in the jungle here in Belize who, sadly, died of cancer a few years ago at the age of 51. Mark Ludwig had a doctorate in particle physics. For his PhD thesis, he had worked out by a different means one of the classic math derivations of modern physics. I marveled that it had not been worked out as he did it long before, but it was not a simple feat. Mark went to MIT, and according to his PhD chemist father, was there less than two years. He had gone through all the undergraduate math and physics and was wondering what to do next. A friend of his was going to Cal Tech, but it was long past the deadline for submission of admission applications as a student. On the letters of recommendation of his physics teachers at MIT he got into graduate school at Cal Tech without having obtained a degree from MIT. The only university degree he ever had was a PhD. Later, he dropped out of the hallowed halls of science at CalTech, in part because of what he observed as the dilution of the pursuit of scientific truth by a pursuit of money by his professors. Then there was a bizarre incident that shattered his hard-headed scientific-materialist outlook. In the Pasadena newspaper, an occult group ran an advertisement guaranteeing a “psychic experience” or your money back. Mark rose to such challenges and, determined to get to the bottom of the ruse, responded to the ad - but he did not ask for his money back. I asked him what happened. He responded: “They told me things that only I knew that they could not possibly have known and in enough detail to convince me that there is more going on in the universe than can be explained on the basis of physics alone.” He subsequently returned home and spent time studying the wider picture of reality, continuing it after returning to a physics school that was not as demanding as CalTech or MIT so that he could do both physics and continue “studies of everything” at the same time.   While at CalTech, Mark was one of only two students who dared to take for credit among a class full of auditors Feynman’s course in advanced mathematical methods for physics. The other was Stephen Wolfram who is known for his contributions to symbolic computing of mathematics. Like Thorson, Mark was also not entirely impressed with Feynman’s teaching style, though he was interacting with someone of similar ability. One of Feynman’s colleagues at Cal Tech was the father of Ralph Leighton. Ralph was a school teacher and young friend of Feynman. Both of them had an interest in drumming, and they had drumming sessions together and even built drums. At these sessions, the raconteur (story-teller) Feynman would tell of events from his past. The younger Ralph began to realize that these stories were extraordinary - a goldmine of tales! He brought his tape recorder - an ordinary machine and not of studio quality - to tape them. He then transcribed them into what became the longest top-selling book on the New York Times best-seller list at that time, titled Surely You’re Joking, Mr. Feynman: Adventures of a Curious Character. I later wrote to Ralph that the subtitle was ambiguous in that it could be taken two different ways. He and Feynman had already thought about it and knew of three different meanings. Later in life, while the Soviet Union still existed, Feynman had an interest - kind of a fetish curiosity - about Tannu Tuva, an obscure part of the Soviet Union in Central Asia. The capital city was Kyzyl, and lacking any vowels, Feynman thought that it just had to be an interesting place, a country with a capital having a name with no vowels. (Russian head of state, Vlad Putin, recently disappeared for a week to Tuva on vacation, and did some fishing.) Ralph was Feynman’s co-laborer in the effort to go there. Feynman got a California license plate that said “TOUVA” on it and was trying to devise means of going to the place that was off-limits by the Soviets. He offered to give physics lectures in Moscow, to which the Soviets agreed, and then he could visit Tuva. No, Feynman objected; Tuva first, then the lectures. It was declined. Leighton wrote a book on the project, Richard Feynman’s Last Journey: Tuva or Bust! (W.W. Norton, 1991). Before I tapped into Leighton’s Friends of Tuva website, I had gone to an IEEE conference in Miami, Florida on signal processing and had run across Alan Oppenheim who taught DSP at MIT. At Tektronix, I took his videotape course and was impressed by his mastery of the subject and his ability to deliver highly-refined lectures. I met and talked with him at the conference. (Small world: his sister and my brother Kenneth were working together in heart surgery in Portland, Oregon over that summer while Ken was in medical school.) Oppenheim had developed an extension of linear filtering he called homomorphic filtering. In one of his videotape lectures he explained it and then played an aria of Enrico Caruso from an old 78 rpm vinyl record that had been filtered. It was memorable; Caruso’s tenor voice was filtered out from the background orchestra and it was as though he were singing a capela, with no hint of an orchestra behind him or of scratches on the record. Years later, Ralph began to offer through his Friends of Tuva website audiotape copies of his better recordings. I bought a copy of each of them and was keen to get others of lesser quality. I wrote to Ralph, with homomorphic filtering impressed on my memory, and suggested that he talk with Oppenheim about the tapes. In February 1995 he wrote back on a postcard: “Al Oppenheim has sent me some sound-reduced tapes that are promising. He’s definitely the guy with the know-how. Thanks for the lead!” Some complications arose for Ralph’s purposes and he later wrote a note saying: “MIT’s solution (algorithm) was not well suited for the job, but “Sonic Solution’s No-Noise” did the trick. Thanks for the impetus to get it done!” Oppenheim had referred him to a sound lab in Utah that accomplished the task. The “tapes” are available in digital format and can be downloaded for a very modest price (some free) from Welcome to Feynman Online! Feynman’s safecracker story - one of his best, about how he picked the lock on a safe that contained all of the detailed secrets of the atomic bomb - has also been put in cartoon form as a “Two-Fisted Science” booklet from Gemstone Publishing, P.O. Box 469, West Plains, MO 65775; tel.: 417-256-2224; Two-Fisted_Science@umich.edu I end with a final story about Feynman from another of his students. An acquaintance of mine, Don Page, a physicist at the U. of Alberta at the time of telling of this story, was reminded that during his physics PhD candidacy exam, after failing to give a good explanation of quantum emission from black holes shortly after Stephen Hawking’s prediction of it (when he had been working on the problem himself before Hawking and so in principle, he wrote, could have made the prediction himself “if only I had been much more competent”) was humiliated by being told by Feynman: “Quantum mechanics was invented in 1926. Now it is 1972. You should learn quantum mechanics.” But, he wrote, my embarrassment was mollified somewhat when other members of the committee said, “Dick, Dick, it’s 1973.” Dennis Feucht has his own laboratory, Innovatia, on a jungle hilltop in Belize, where he performs electronics research, technical writing, and helps others with product development. He wrote a four-volume book-set on analog circuit design, has completed a book on transistor amplifier design and is working on a book on power electronics.  
  • 热度 3
    2014-10-3 12:08
    1007 次阅读|
    0 个评论
    Red Wine Audio, a battery-powered audio equipment company, displayed an unusual modular integrated amplifier at the recent New York Audio Show. No, I'm not talking about the change in brand from the usual Red Wine Audio to Vinnie Rossie (the founder). Instead of a battery, the amplifier uses ultracapacitors. Yes, you read that right! The amp has 18 ultracapacitors in two banks, reports the Stereophile magazine. The report says the capacitors were developed for use in automotive regenerative braking systems. The two banks allow for one to charge while the other is discharging—the switching, I understand from other reports, is seamlessly implemented. So what's the benefit? Really fast charging and really long battery life—rechargeable batteries offer limited charge-discharge cycles. Clever design. Oh, I almost forgot to explain how the Vinnie Rossie Lio is modular. Like many of the company's products, you can customise it with your choice of modules: a DAC-preamp, a phono preamp, an integrated amplifier, a headphone amplifier, etc. Red Wine Audio's home page at http://redwineaudio.com/ says the product will be released this month. --Vivek Nanda
  • 热度 4
    2014-7-4 15:30
    467 次阅读|
    0 个评论
      2014 CSR audio seminar data(2014 CSR AUDIO大会相关文档资料) 资料下载链接:http://pan.baidu.com/s/1hqpBBDy   包含如下文档: CS-315730-DC-2-Audio_Portfolio_Overview.pdf CS-315731-DC-3-ADK3.0_An_enhanced_toolkit_for_differentiated_audio_consumer.pdf CS-315732-DC-3-Making_use_of_GAIA_on_ADK3.0.pdf CS-315733-DC-2-Making_use_of_GAIA_in_CSR_s_ROM_products.pdf CS-315734-DC-3-Making_an_Android_App_work.pdf CS-315735-DC-2-How to implement shareme in ADK3.0.pdf CS-315736-DC-2-Designing_for_the_best_RF.pdf CS-315737-DC-2-Designing_to_get_the_best_out_of_2-Mic_CVC.pdf CS-315738-DC-2-Overview_of_the_CSR_Soundbar_platform_portfolio.pdf CS-315739-DC-3-Update_on_the_CSR_Beethoven_Soundbar_platform.pdf CS-315741-DC-3-CSR_Beethoven_Technical_Overview.pdf CS-315742-DC-3-Update_on_the_CSR_Mozart_Soundbar_platform.pdf CS-315743-DC-2-How_to_configure_CSR_s_Subwoofer.pdf CS-315744-DC-3-BT_Speaker_Platform_Roadmap_update.pdf CS-315745-DC-2-CSR8675.pdf CS-315746-DC-3-Product_differentiation_using_eXtension_partner_solutions.pdf CS-315747-DC-2-OTA_DFU_walkthrough.pdf CS-315748-DC-2-aptX_Update.pdf CS-315749-DC-2-TWS_Technical_deep-dive.pdf CS-315750-DC-2-VibeHub_Introduction.pdf   方案交流QQ1991674357
  • 热度 9
    2013-11-24 19:56
    814 次阅读|
    1 个评论
    USB is typically used to carry digitized audio. After all, even USB 1.1 has the bandwidth. You may have USB speakers or you may stream audio from a hard drive that's connected to your computer through a USB cable. Can you hear the distortion that the USB link adds to your music? Some people think they can. I recently received a link that, as connections go, is absolutely hilarious. The Absolute Sound, a site for audiophiles, posted its 2013 TAS Editors' Choice Awards: Digital Interconnects . Let's start with the first one. Here goes, and I quote: AudioQuest Diamond 0.75m, $549; 1.5m, $695 audioquest.com This über-expensive USB cable is simply revelatory in its combination of ease and refinement on one hand, and resolution and transparency on the other. Although capable of resolving the finest detail, Diamond USB has a relaxed quality that fosters deep musical involvement. Deep musical involvement? We're talking a digital cable here. Audiophiles, please get your ears out of the sand and listen to me. USB is a digital bus. As long as the receiver can properly receive the bits and tell the difference between a logic 1 and a logic 0, the digital representation of the audio at the receiver's output will be a perfect replica of that which was transmitted. You claim that you can hear the difference between an inexpensive and expensive USB cable? I'm sorry, but you have been deceived. On average, digital links deliver one bit error for every 10 12 bits sent. You can't possibly hear that. Next, you'll tell me that you can hear the difference in clock jitter produced by that inexpensive cable. Again, as long as the bits are properly interpreted, there is no difference in signal as a result of a cable. If there is any distortion in the entire audio chain, it's on the analogue side. Any time you convert a digital representation of audio into an analogue signal, there is some distortion added. I refuse to believe that anyone can hear that distortion in any good audio system. A top notch audio analyser might detect a difference, but not your ears. Now, I can understand not buying the cheapest of USB cables, but I'd do that for reliability, not audio quality. Don't fool yourself. Paying $695 for a USB cable will not get you better audio. You will get the same audio quality from a $6.95 cable. The audio quality is a function of the original encoding, the decoding, the analogue signal processing and amplifier, and the speaker. Go ahead, prove me wrong. Get yourself a top-of-the-line audio analyser and show me the difference in audio quality between cables that carry digital signals. Take a look at the linked page above. Be sure to read the comments over there as well, and then tell us what you think. This article was originally published on The Connecting Edge. Martin Rowe Senior Technical Editor EE Times  
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