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"Valve Amplifiers, 4th edition" by Morgan Jones
The brand new, fourth edition is finally here, eight years of waiting = big expectations. As expected, the new one is following the old path - the „core" of the book is running through all the editions, with new chapters, plus some additions and rewritings of the old chapters. What´s „hot", and what`s new and interesting? Apart of some new diagrams, one-liners and additions to the old chapters, probably the most interesting is a „new" CCS, DN2540N5 based. Well, we used it in this forum extensively for years, but the difference between forum posts („use it with >10 mA, and ΔV > 15 V") and the book (equations, diagrams, measurements) can be large for someone. He used this CCS as the base for a shunt regulator (CCS „into" Zener stack), and this PS is very interesting too. Well, I can`t supress a little smile, similar PCB with CCS into 8x6V2 (48V "Phantom Power") is in front of me, and many other DIY-ers and manufacturers used this (and even more advanced) tehniques for many years. But, here we get noise measurements of various gas reference tubes and Zener stacks, etc. And yes, Morgan Jones actually used PSUD2, (and probably more important) demonstrated how to properly use it. Who knows, maybe in the 5th eddition we´ll get SPICE simulations and tube models? There is a brand new hybrid balanced RIAA preamp, Baxandall tone control with EF184 pentode, and just one new amplifier, parallel PP with 6S4A output tubes. And what`s old and IMO, boring? Huh, again - there`re no SETs, especially there`re no DHTs, if we don`t count his strange „Scrapbox Chalenge" SET with 6528 tube. Here it is. Again. And even more strange, complicated and sophisticated „Crystal Place" amplifier. Again. Only one (and may I say again ˝odd") new power amplifier. LM317 regulator...probably it will be NOS in 5th edition? And probably the largest dissapointment is distortion measurements chapter - the same after all this years. Yes, various 6SN7 rules, and there was (obviously) no need to measure any other tube in the last 8 years?! To be fair, there`re some new distortion measurements things here and there, for example distortion cancelation, WE eq, etc. I can`t stop thinking that realisation of this book is 5 years delayed. No, it`s not somehow „old fashioned", but much information here is „old news" for various ambitious DIY-ers on various forums. Yes, in the end of this short review of this big book (~700 pages!) the question is: „I have the 3rd edition, do I really need the 4th?" And my subjective answer is yes, absolutely. Despite some criticism above, Morgan Jones book(s) are miles ahead of similar stuff, his writing style is superb, and information about many things tube-related (RIAA, for example) are top-notch. Reccomended!
Re: "Valve Amplifiers, 4th edition" by Morgan Jones
Hi, Good evaluation. Now I won't have to buy it. I read number 4 and after a while felt that much of the information was dated. I do think that it is a worthwhile thing for someone new to audio to read though. A lot of information is useful. Funny thing is I don't use 6SN7s as they are noisier than other tubes I use and I do use LM317s in "Odd" circuits. PSpice? What's that? Something you put on food? Just kidding. It is useful in establishing starting points in tube designs. From there is usually has to go the hard way with testing and evaluation to get things to really work like you want. Good write up.