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My Treasure – "Tube amp making course" By Otomeijin (September 2, 2005) 1.Introduction: Vol. Introduction to the amp world This is going to be the "tube amp (hereinafter called amp) making course" for "beginners" based on my capability upon request of e-mail magazine readers and desire of Hi Fi Do to "let many people know pleasures through audio equipments". If your level is more than the intermediate level, please sit back and watch what we are doing. The amp world would become more exciting if you point out some mistakes or advise me some tips and know-how. Anyway "Let's get started! I would like to hear your shout encouragement and handclaps!"

There are too many items about the "amp world" to name. We can't ignore each item though, it will sure take a lot of energy and time to get right into it. Maybe you want to choose to study over saving your energy and time. However I know you want to make an amp right now and listen to music with that. But then you will get stuck in a tunnel with no light at the end when you start making it. This is why I accepted to give this course wanting to guide you to the end of such a tunnel. Like you have already noticed, I am not that familiar with the electric theory etc. Even if I could understand that, it's been almost half a century since I had studied so I forgot it all. However I can still teach you some must-dos (knowledge, technique and affection(?)) which will be minimally required for the "amp world", and then I would be happy if you acquire all of that. After that, you can enjoy learning and making amps by yourself. There are also many ABC books on amp making, circuit examples and theory books in store so that you can choose whatever you like depending on your level. And you may want to join some kind of amp club in your area or the one organized by some manufacturer so that you can learn from ("gentle") senior members from A to Z. And I hope you remember and miss me "the man lost in sound". You might be only one "beginner" among all the readers but I will try my best for you. The secret of the "amp world" is to take it easy without haste through this 2-month course. The senior amp makers used to be unfamiliar with anything just like you. The amp that you make on your own will respond your expectation for sure. If you know some basic stuffs already, please skip it and start from the practical module of the course. However, I hope you don't get freaked out from there.
2.Vol. Story that is too late to check: What is the amp? When searching it in the dictionary, it says "amplifier". What is the function of amp in audio equipments? The amp amplifies the small audio signal from a record player or radio with using electricity, and vibrates the air in a wide space by driving speakers to produce sound and transmit so-called sensation to us. It seems there is no action in the amp at a glance. However, electricity is flowing a great deal like "ding-dong". The pilot lamp lights up upon switching and the heater of the vacuum tube turns red, which looks as if the amp were alive. And if this one has a wattmeter, it will show how active the amp works by swinging its needle. The basic role of the amp in audio system is; (1) to amplify, adjust and regulate the audio signal, which is called control amp or pre-amp. (Picture)
	(2) to amplify the power to drive speakers, which is called power amp or main amp. (Picture) The amp built separately is called separate amp, and pre-main amp for all in one. The name is a bit different depending on the configuration. Even though there is a little difference in amplifying, the amp handles the electricity. The amp is called the voltage amplifier on the circuit whose function is to change the voltage.

3.Vol. What should we make then? This time we will make the relatively easy-to-make "tube power amp" and use the "Kit". There are various approaches for making the amp. The one of them is to design on your own, collect necessary parts and build them after processing the chassis like I did a long time ago. And another one is to build up from the kit. It seems that you need to have some technical knowledge for the former approach but at the same time you will have fun. However, basically you need to take all the risks on your own. On the other hand, for the latter approach, the works will be easier with the help from a kit seller and risks will be shared with the kit seller. So I would suggest you to use the kit unless you are experienced, have a lot of time to spend or can easily find the necessary parts nearby. If I were you, I would use the kit for sure now. Speaking of the kit, the kit level, which means the degree of processing, with or without a printed-circuit board, the level of the instruction manual and so on, varies a lot depending on kit maker actually. The kit is pretty expensive to be chucked away by saying, "It is too difficult to build". So please thoughtfully choose the one suitable for you depending on the degree of your preparedness by checking on some brochures. This time Hi Fi Do found the time-proven kit suitable for this course. I thought this kit would be one of the appropriate kits for beginners in the "amp world" when I unpacked and checked it out.
I will inform of the schedule of the course. Otomeijin is still a human, I might have a headache or cold sometimes. So please stick to it with me. Besides my computer is pretty old and showing "fatigue symptoms" so I'm anxious whether it can survive till the end of the course. But I will try my best. Sept 2: Introductory Chapter --- " Introduction to the amp world" (this time) Sept 9: Chapter 1. Part 1 --- See the light "Vacuum tube" (Hereinafter the title is provisional.) Sept 16: Chapter 1. Part 2 --- See the light "Circuit component". Sept 23: Chapter 2. --- See the light "Work process and Soldering. Sept 30: Chapters 3 --- Let's try it out! Exciting practical module. Oct 7: Final Chapter --- Throbbing to touching moment or nail-biting moment? To be continued.

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