Jul 8
Patrick, why dont you collect your interesting writings in a book? You could sell it as a PDF download on your site. I would buy one.
Martin
Hi Martin,
There are many good good reasons why I probably will never make a book from my website,now about 53MB.
First is the almost infinitesimal number of ppl who'd pay me $50 for a decent book about audio, solid cover, A4 pages. At least a few Ppl quite like my website and most find it if they type say "modify Quad-II" into Google, then eventually end up at my site which gives much more info about Quad-II than everyone else.
(((But you could look at Phils' website at
www.philatronics where he has 50 more pages about Quad-II than I have, all perfectly correct,plus 100% one eyed, complete with denials that anyone else could be right about anything.)))
Today's ppl don't need books any more to build a decent amp. They just search around to find the best source of info according to their uneducated, inexperienced and incompetent background, just like an office worker who has never got his hands dirty might decide to renovate his kitchen without employing a carpenter. I spent 25 years as a licensed builder specializing in house extensions and I got a pretty good idea about how many ppl went about their house "improvements" before hiring me. I also had clients who had just married, back from honeymoon, then they buy an old established house, only to discover the previous list of very badly done amateur house "improvements" that escaped the notice of dopey property assessment "professionals", used to see if the house was a good deal before buying. Previous dopey owners had done their utmost to do stuff without learning or experience, and while taking ludicrous shortcuts which would never have passed any inspection by engineers or regulatory authorities.
The same "people attitude" is found amoung DIY tube electronicanistas. The ppl who dabble ignorantly without asking enough questions or being humble have a rule, "Thou shalt not spend any money on a hobby". If their dumb missus wants a new kitchen, they whip out the yellow pages and sign up a kitchen "expert" who gets paid enormous sums of money which is invisible because its paid via credit card. After the kitchen is given the make over, it makes the missus feel pleased because she knows its better than her friend's kitchen and she then gives hubby a ****. BUT, dinner tastes just the same. Hubby continues with amp work, taking years to get complete, and no, he ain't gonna buy any book.
During 18 in the audio-trade, I dealt with many DIYers all trying to avoid expense, just get a cheap amp. Of many who tried to make their own systems, only 10% had a working system after 5 years, and one I'd be pleased to listen to.
Second reason is that to make a good book, as opposed to producing a large bunch of crap like many others, you need to spend a huge amount of time re-editing a website to suit book like use, with page numbers and so on, just like RDH4, and with index and removal of repeated ideas and theories, etc, etc, etc, so at one click, you can download the whole damn lot and there's your book, and it prints out nicely, and can be a bound set of volumes.
Let's face it, using RDH4's index is easier than trying add text links.
But then as my site is, if someone does download the lot, they can subject it all to a **search program**, type in say, "negative feedback", and they will be deluged with readable sentences or paragraphs about NFB. BUT, they'd read this stuff out of context, while feeling extreme reluctance to read old books which have much more to say about NFB than I have included. There isn't room at my site to fit repetition of what better minds than mine have written about electronics. Knowledge about tube use was 90% established by 1960, and ppl need to realize that to answer all questions their mind asks - if they have a questioning mind - they must read a lot more than what they find at my website.
So, I've tried to make each page about each type of amplifier at my site say enough about that amp without needing ppl to go on long searches and re-interpretations of ideas, so every amp that has any NFB has a description about it. Maybe I please some ppl, and displease others. To those I displease, I say they can prepare my site as a book for themselves if they wish. Its all in WYSIWYG, and free, and no copy-write. Nobody could thus make any money selling their book of my site because the info is already out there, and ppl hate paying.
Intelligent readers and doers might find out that our dear Phil isn't completely correct about everything and that the brevity of his posts often leave out an enormous amount, and include rather shortsighted statements. His latest clanger was about THD produced by EF86 in Quad-II having far more THD than output stages.
Sorry, Phil, I don't believe the general statement.
Fact is, you can always design a better amp than Peter Walker, Harold Leak, or Mr Radford foisted upon the buyers in 1950s and 1960s. They were the Men Who Made Us Pay. Just 3 among so many. Consumer electronics. You can do better!!! and without the bean counting mindset behind each and every mass produced item.
I have not seen the 6DJ8 cascode input stages for Quad-II and which Keith Snook allegedly has at his website. Probably, it works OK, because a cascoded 6DJ8 forms a gain unit similar to a pentode, and the paraphase Quad input idea could be used with little change. Theoretically, the 6DJ8 offer lower noise. The use of cascode was originally mainly for RF apps but was later adopted for AF use and a classic example from 1950s was the Hedge circuit for driving a UL output stage with EL34. The cascode is efficient because Iadc of top triode flows in triode below, ( totem pole config ) thus current need for the input/driver is low, and B+ filtering is easier, and so Hedge circuit and others delight the aspiring wannabe idiot maker who wants to save pennies.
Probably, the best input / driver arrangement for Quad-II involves 2 twin triodes to replace EF86, with SET input with paralleled twin triode
and an LTP driver stage. I first used this in 1998 with 12AT7 input and 12AU7 LTP, with bjt used for cathode CCS. It's a very hard input / driver to beat, in terms of bandwidth, noise, gain, THD and low Ro to drive output grids. There is no paraphase needed. Using 2 x 6DJ8 would be very good in the same circuit.
But just changing the input/driver of Quad-II is not enough to get these old amps to perform bit better. You need total PSU make over. By the time you fix all the shortcomings of Quad-II, including installation of a better OPT, you don't have a Quad-II any more. Good, because what you have is better.
The other reason for no need for me to make a book is that there is a record of what my silly old mind has said about audio matters at say rec.audio.tubes since 2001 is there in archives someplace. The quantity exceeds what everyone else said all summed together. That alone doesn't make me an author worth buying. It just means I was a bit interested in tube audio, take it or leave it.
Trends now indicate interest among the general population has dropped -20dB since 2001 because tube audio was mainly about old blokes doing what old blokes do, and old blokes are depressingly temporary, and end up unable to solder anything or hear any music, or appreciate it, or need it while making love to a wife / lover. The new generation hasn't any time, they clutter their minds so badly with friperous needless junk that they cannot think deeply about anything let alone make anything, or be happy, and the world has more efficient ways of fooling everyone to buy more junk.
I don't have, and will not have a mobile phone.
I do not need to make my sound system better, or different.
Patrick Turner.