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"The Development History of Preamplifier Circuit Design" is a review article written by the Japanese Shigeharu Kore-eda. According to my estimation, the original Japanese article is likely to be published in the Japanese magazine "Radio Technology" or "Wireless and Experimental" (ie MJ Magazine).
What I have is printed in the first volume of the July 1988 first edition of the "Audio and Television Technology Collection" series of "Audio and Television" launched by Shanghai Translation and Publishing Company more than ten years ago. The book "Collection" was sold in sets of two volumes, priced at 8.65 yuan at the time. It was a relatively expensive book at the time. I bought it in January 1989. The original book shows that this translation was first published in the 1987 issue 2 of "Beiwu Communication" (an internal communication of Beijing Radio Factory?)
That day, a netizen in this forum had a fever and his girlfriend said it was a "rare book", so I paid special attention to it. After checking the print number, it showed 1-15,000 copies, which is considered average. I believe there are many people today who do not have this book or read this article. Several audio enthusiasts and electronic enthusiasts I know don’t have this book either. The fever girl must have been right, but the actual print run was not large and it became a "rare book".
The British philosopher Bacon said that reading history can make people clear their minds. My understanding of this sentence is that reading history can clear your mind, because facts have proven time and again that the history of the past often repeats itself today. Although this article is about the history of circuit development and is highly technical, it talks about much more than technology. Through this article, you may discover that various phenomena and weird phenomena in the audio industry today have already occurred and appeared in the past. Therefore, I recommend this very technical article to all netizens. If there is any inappropriateness, please forgive me.
This article only talks about the circuit of the preamplifier, and most of the text is about the design of the LP cartridge, and it only covers the early 1980s. But over the past 10 years, I have read this article no less than twenty or thirty times, and it has been deeply engraved in my mind. If there is anything that affects my view of audio, apart from my own personal practice, it would be this article, because I feel that any audio article I have read cannot compare with it. I often think about how great it would be if there were articles that discussed power amplifiers, sound sources, and speakers at the same high level!
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(The following is the "after-reading" of what I wrote - composed of question marks: D: D: D)
Every time I reread this article "The Development History of Preamplifier Circuit Design", it always makes me think and feel a lot. Even today, when I look at this article and flip through the dozens of pages of notes I took from English DIY forums over the past few months, I still have many thoughts and even more questions:
————1. What do you think of the classic instruments from decades ago? Is today's audio equipment really better than that of the previous, second or third generation?
The Tannoy AUTOGRAH speakers mentioned in this article are still advertised for sale in the Japanese "Wireless and Experimental" magazine (MJ Magazine) that I have. I also remember how highly the player writer named Slingshot Yang in the Hong Kong audiophile magazine played JBL’s very early horn stage speakers a few years ago.
————2. See the clumsy QUAD 33 circuit mentioned in it. No matter how you look at it, its circuit structure is exactly the same as that of our radio cassette players back then. Does this really confirm what the original author said that technology alone is not enough? Thinking further, does equipment design and manufacturing put technology first? Does it need to have cultural heritage?
————3. The JBL SG-520 preamp mentioned in the article (it seems to be still sold in the Japanese market today for about 20,000 yuan) actually uses germanium tubes, which is well known in the electronics industry. Devices can also achieve such good sound effects. The article also mentions that high-quality components are required to assemble a DC amplifier. These two places are talking about devices. Aren’t the statements contradictory? Is the quality of parts really that absolutely important? Should we also replace the machine with JENSON copper tube silver film capacitors worth 2,000 to 3,000 yuan today?
————4. The article said that transistor equipment (which should include circuit design) began to appear in large numbers in the 1970s and 1980s.
Isn’t it still the same today? Which manufacturer is not rushing to launch new models? Is the purpose to steal money?
Looking at the circuit forms of amplifiers, how many circuits can truly surpass those before the 1980s? Aren’t the new circuits and new technologies of many amplifiers that manufacturers have repeatedly claimed to be mere speculation? How much bluffing stuff is there?
Mr. Nelson Pass, the founder of the famous American manufacturers Threshold and Pass, a famous sound designer, and owner of multiple circuit design patents, once said seriously in the DIYAudio forum: Today's 95 Hi-End front The circuit of the preamplifier is not as good as the early JC-2 preamplifier of Maiji (this machine is earlier than the LNP-2 specifically introduced in the "History of Preamplifier Design Development"), and the circuit of today's 95 Hi-End power amplifier is not as good as Get KRELL's first fan version machine KSA50.
Editor-in-chief of Hong Kong audiophile magazine Chen Yingguang wrote in an article introducing second-hand equipment in 1993 that many people in the industry believe that KRELL’s first KSA50 is its pinnacle product and has the most beautiful sound. . This corroborates what Pass said.
sq03 2004-8-29 11:22
Reflections after reading "The Development History of Preamplifier Circuit Design"
5. Is today's audio highly commercialized? Already? Is the quality of audio equipment as good as the media says? How much has the media blinded us?
Investigated netizens in the English DIY forum said that the Philips turntable CDM12 PRO currently used in European and American HIEND digital equipment is far inferior to its first-generation all-metal turntable CDM1. There are other ghost netizens arguing that the reason is: when the first generation turntable was designed, the manufacturer had a lot of thoughts on the product, so it did not hesitate to use the most stable technical methods. When the second generation was produced, the manufacturer knew more and began to simplify it. The further back you go, the more this happens, thus causing the sound quality to deteriorate.
Can this be regarded as a "result" display of the commercialization of audio?
Speaking of commercialization, I would like to quote a post I wrote earlier when discussing whether advanced turntables are a money scam
Some things that are technically very simple, get In the market, that's not the case.
N years ago, when I was still on campus, when I read an article in "Radio" magazine about the production of recorders using single-chip recording and playback ICs, it suddenly occurred to me that all recording media include tapes, video tapes, optical disks, and hard disks. , one day, it will be replaced by integrated circuit memory. To this day, my basic concept has not changed (in fact, the situation is also developing in this direction), but I have made some modifications to my ideas about the implementation process.
Everyone has seen that USB flash drives with dozens of MB have now entered thousands of households. I believe that with the development of large-scale integrated circuit technology and the expansion of output, USB flash drives with hundreds of MB or even dozens of GB ( The price of memory) will be reduced to ten yuan or eighty yuan soon.
These are the best products to replace inconvenient storage media such as tapes. To be honest, there are no technical problems - with my limited knowledge and the technical implementation methods, haven't hard disk video recorders been made?
But why is there no action in the market? I’m afraid the answer lies in business.
Do you remember how DAT, which was once highly regarded for its excellent sound quality, fell into decline? When some African countries produce and sell low-priced AIDS drugs, don't American companies that sell expensive AIDS drugs sue them for infringement? Aren't there some foreign factories that collect technology patent fees for the production of DVD players in our country?
When you think that "the price of turntables can be reduced" using fairly simple technology, when I used to think that high-quality recording and playback can be achieved using simple storage ICs, manufacturers should actually It has been known for a long time, but it may have another plan in mind.
In economics, the nature of capital is to pursue maximum profits. From a manufacturer's perspective, we won't do anything without profit.
Without the huge demand and huge profits generated by the computer market, would CPU and large-scale integrated circuit manufacturing technology develop so fast?
Back to what we were talking about. Just think about it, what does the merchant gain by lowering the price of the turntable? Radio cassette recorders, video recorders, and CD players that use ICs as solid materials or with swappable memory cards are facing accusations of infringement of intellectual property rights. Who would want to wade into this muddy water? Even after supplementing the development of an anti-infringement technology, it is inevitable to encounter problems such as interfaces and specifications, etc., all of which cannot escape patent fees (without these patent fees to attract, there will be a lack of motivation for market promotion). Okay, once other issues including market demand are solved, what price will it be in the hands of our consumers?
The good wishes that are within reach are often always so far away in the face of cruel reality, which makes people sigh.
Why not the stereo?
6. Look at those high-end equipment nowadays, which often cost hundreds of thousands or even millions. The power amplifier output does not seem to be rated at less than 200 or 300 watts. Each one is a behemoth, and the internal circuits are more complicated than the last. I can't help but wonder, are we still advocating the big gun and big ship doctrine mentioned in "The History of Preamplifier Design Development" today?
7. The article mentioned that the development of sound sources has led to the evolution of the overall design of equipment. In the mono era, preamplifiers attached great importance to the tone device, but in the stereo era, this device was weakened. Now that we have entered the SACD/DVD era, what are the big changes in equipment? Why not?
8. The current equipment mentioned here generally has a cold tone. Is it true? Is it caused by the sound source it refers to, or is it caused by components produced by cutting corners after being highly industrialized? Or maybe it’s because the auxiliary materials used in the production of parts that can bring warm sounds are not in supply (——- Discussion in the Gui Lao forum mentioned that electrolytic capacitors have better sound after removing the plastic skin; a Gui Lao said on his personal webpage He gave a picture of a modified capacitor case that he used to re-make the capacitor case out of wood; some people even said that plastic can be used without plastic in the equipment, otherwise it will cause bad sound)
Is the cold sound due to today's design orientation? What caused it? A few days ago I saw an article interviewing a famous Japanese designer. I forgot his name. The article said that he participated in the DIY competition organized by MJ in his early years, and later set up his own company 47 LAB to produce audio equipment. One of them was the GainCard, a mini amplifier using the LM3875 integrated circuit (it is said that it only sells for a slap in the face). (as high as RMB 30,000) are being copied by foreign DIYers. In the interview, he clearly pointed out that today's equipment design focuses too much on the reproduction of sound and ignores the reproduction of music. He also said that the JBL, ALTEC, and TANNOY speakers of the 1950s and 1960s are inferior to many modern speakers. It's very musical.
————9. After reading this high-level "History of the Development of Preamplifier Circuit Design", I feel that the Japanese have a lot of experience in audio design, manufacturing, playing, research, DIY, etc. A place worth understanding and even learning from.
I remember Bae Dong-geun, a senior Korean audio reporter, published an article in an influential local newspaper, saying that Japan is the world's largest audio country, which makes sense. Some time ago, an old record on the Home Appliances Forum introduced some of the "big guys" in Japanese audio criticism who loved music so much that they even died at concerts.
Due to historical reasons, the Japanese have a lot of exchanges with the United States. Many good audio equipment in Europe and the United States were discovered by the Japanese and poached one by one. Their tastes may be weird, but they do have a lot of speakers that they have collected and played with, and they have a lot of insights. Slingshot Yang Suo, a veteran audiophile from Hong Kong, praised the old American speakers, but the Japanese had driven up the prices early on. Also benefiting from the early historical relationship, the Japanese have published a series of "History of the Development of Vacuum Tubes", "Vacuum Tube Museum", and "Circuit Inspection of Famous Machines". Although the design and manufacturing at the manufacturer level is not widely recognized in many aspects, technically Japan may not be inferior to any other country, and the same is true for device manufacturing. .
Let’s talk about the DIY situation in Japan, because people from all walks of life report that Japan’s DIY craze is very high, and my little devil is interested in this aspect, and only this aspect of things can be speculated and sold now: D
(1) Akihiko Kaneda mentioned in "The Development History of Preamplifier Circuit Design" is a famous Japanese DC amplifier design DIY master and a long-term author of MJ magazine. It is said in the Gui Lao forum that as an amateur researcher, he has a surprisingly respected status. The author's information shows that by the end of 1998, he had designed and produced 152 pieces of amplifiers and other audio equipment.
(2) MJ magazine also has a regular author, Nobuji Kubota. The preamplifier and power amplifier circuits he designed have long been seen in DIY articles in domestic magazines. He is more famous in our country for the 0DB power amplifier and Kubota-style power supply he designed.
(3) It is reported that there are three DIYers in Japan who are very influential in European and American countries.
One is Shun Sakuma, who specializes in direct heating amplifiers. The wiring is very simple, almost all using direct heating tubes and transformer coupling. There are personal homepages on the Internet.
The second is Nan Liangping. He has only published three DAC articles (circuit). A decoder made of a TDA1543 integrated circuit worth no more than 10 yuan participated in MJ magazine’s homemade decoder competition for the first time and tied for first place in the sound quality project. The non-oversampling technology used (NON OVERSAMPLING in English, which is actually a retrograde technology that cancels digital filters, but he has theoretically proven that it is better than oversampling in some aspects), is now used by people on the English DIY forum. Netizens strive to use it in their homemade DACs.
The third place is JEAN HIRAGA. French and Japanese. According to an article reprinted from Taiwan, it was he who introduced 300B to Europe, which triggered the worldwide 300B craze. This person also published a series of articles on the extremely simple pure Class A low-power amplifier he designed in a European magazine, which had a great impact.