[Patrick Turner]

A short note to all:-
I was not completely happy with my old page on re-forming Quad-II amps for improved performance.

So I have now re-edited all schematics and removed much BS and added more possibly useful stuff over the last month.

http://www.turneraudio.com.au/quad2powerampmods.htm

I consider myself well pre-battered by Quad-II zealotistas wielding baseball bats so no more damage can be done to me, so please, provide your own vomit bucket when you read my website pages :-)

Patrick Turner.

[Phil Allison[_3_]]

"Patrick Turner"

A short note to all:-

I was not completely happy with my old page on re-forming Quad-II amps for
improved performance.


** Nor was anyone else .

So I have now re-edited all schematics and removed much BS and added more
possibly useful stuff over the last month.

http://www.turneraudio.com.au/quad2powerampmods.htm

** The notion that the dual EF86 stage has less THD than the output stage
need correcting.

It does not, it has far more - about 5 times in fact - do our own test,
with the EF86s removed .

The correct result is in the vicinity of 0.2% THD at 10 watts and 1kHz
rising to 0.6% at 15 watts.


I consider myself well pre-battered by Quad-II zealotistas

** The Turneroid is like that mythical duck that all water runs off.

For "water" read rational thinking and fair criticism.

Quack, quack.....


..... Phil

[mick]

On Thu, 26 Jun 2014 20:17:43 +1000, Phil Allison wrote:

"Patrick Turner"

A short note to all:-

I was not completely happy with my old page on re-forming Quad-II amps
for improved performance.


** Nor was anyone else .

So I have now re-edited all schematics and removed much BS and added
more possibly useful stuff over the last month.

http://www.turneraudio.com.au/quad2powerampmods.htm

** The notion that the dual EF86 stage has less THD than the output
stage need correcting.

It does not, it has far more - about 5 times in fact - do our own test,
with the EF86s removed .

The correct result is in the vicinity of 0.2% THD at 10 watts and 1kHz
rising to 0.6% at 15 watts.


I consider myself well pre-battered by Quad-II zealotistas

** The Turneroid is like that mythical duck that all water runs off.

For "water" read rational thinking and fair criticism.

Quack, quack.....



As a matter of interest, Phil, have you tried the circuit that Keith Snook
has on his web page, where he uses cascode ECC88s instead of EF86s? It's
still basically the same circuit as Quads, but with triodes.


.... Phil

[Phil Allison[_3_]]

"mick"

As a matter of interest, Phil, have you tried the circuit that Keith Snook
has on his web page, where he uses cascode ECC88s instead of EF86s?


** Huh ??

Have you read anything I wrote at all?



..... Phil

[mick]

On Mon, 30 Jun 2014 23:13:16 +1000, Phil Allison wrote:

"mick"

As a matter of interest, Phil, have you tried the circuit that Keith
Snook has on his web page, where he uses cascode ECC88s instead of
EF86s?


** Huh ??

Have you read anything I wrote at all?



I did, Phil, yes.
I noted that you said about that site (in reply to Pat)
"** Certainly long on trivial details and fetish stuff.

But very short on anything really worthwhile.",
which I'm not going to argue with, but I wondered if you had actually
tried that idea. I suspect that any additional bandwidth possible from
the cascode would be wasted, although the gain should be ok. Whether it
would be worth looking at I don't know, with a higher heater drain and
(probably) the need to bias the heaters up because of the 50v Vkf for a
ECC88.

I'm not thinking of modifying any Quad IIs (I can't afford any!).

[[email protected]]

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

[Patrick Turner]

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.

[mick]

On Fri, 18 Jul 2014 20:05:30 -0700, Patrick Turner wrote:

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.)))

snip


Thanks Patrick! A good read as usual.
I'm not sure that Phil's website is still there. I couldn't find it, even
by changing the spelling etc.

[Phil Allison[_3_]]

"mick"

Thanks Patrick! A good read as usual.
I'm not sure that Phil's website is still there. I couldn't find it, even
by changing the spelling etc.


** You just been "poned" - sonny boy.

I do have a few articles published on the net - all of them on this site:

http://sound.westhost.com/absw.htm

http://sound.westhost.com/articles/speaker-failure.html

http://sound.westhost.com/vi.htm

http://sound.westhost.com/project66.htm

http://sound.westhost.com/project86.htm

http://sound.westhost.com/project67.htm


FYI:

The articles are entirely my own work, despite the site owner's name
appearing in some headings.



..... Phil

[mick]

On Sat, 19 Jul 2014 19:10:01 +1000, Phil Allison wrote:

"mick"

Thanks Patrick! A good read as usual.
I'm not sure that Phil's website is still there. I couldn't find it,
even by changing the spelling etc.


** You just been "poned" - sonny boy.

I do have a few articles published on the net - all of them on this
site:

http://sound.westhost.com/absw.htm

http://sound.westhost.com/articles/speaker-failure.html

http://sound.westhost.com/vi.htm

http://sound.westhost.com/project66.htm

http://sound.westhost.com/project86.htm

http://sound.westhost.com/project67.htm


FYI:

The articles are entirely my own work, despite the site owner's name
appearing in some headings.



Thanks Phil, I'll have a read.

[Patrick Turner]

Thanks Patrick! A good read as usual.
I'm not sure that Phil's website is still there. I couldn't find it, even
by changing the spelling etc.

Gee, I would have thought Phil would have so much pride in what he thinks that he'd have to have a website of his own that was maintained properly, and one to give piles and piles of info about Quad-II and tube audio in general. Alas, there is no website. You'll just have to forgive me for typing my sarcastic hope that Phil would have had the website I mentioned. I have "sensus humarius warperiae". The reality is that Our Dear Phil has yet to get around to carefully crafting his own website which would then show an enormous pile of useful stuff about tube audio.

But he does have published articles at the westhost.com addresses.
Those addresses are real and the site is quite large and there is much that is useful to some ppl. I've often visited the site to look at various schematics for this and that and its always handy to appraise what others do to better know what you wish to do for yourself without blindly trying to copy somebody else's schematics. Through the efforts of others, we know them better and ourselves. Through our experiments trying ideas on bread boards and with building umpteen complete amp systems we grow wise, and none of this can happily proceed if anyone takes himself or his ideas too seriously. So while you learn, be prepared to admit along the way that what you thought might have been true last week was just BS, so admit it and move on, and try harder. See the merits, make sure they can be proven. Always look for a better way.

1950s was a time when so many UK audio gear makers rested on their laurels. Competition blitzed them. The Japs gave us Hondas and they went better than the old AJS or Triumph.
I had a two gutless wonder 250cc BSA bikes, then "Matchless" 500 single followed by a 650 ex police bike. They broke down very often, keeping me poor, and off the road when I didn't want it. So bought a spare Honda 100cc which gave gave much better reliability while I flogged it along everywhere I went, often with a suitable nice ****able shiela on the back. Matchless 500cc single would vibrate a lot,had loud exhaust and while it ran even local conservative moral shielas got very excited. But they didn't ****. Ah, such jolly times! Back then, during my Ancient History, nobody I knew could afford Quad gear of any kind. Damned expensive. Few of us had any sound gear let alone hi-fi gear. I quite liked making music with the others in a folk music band for awhile. Great chick puller. But they were all tarts - wanted to **** everyone - not worth serious pursuit. Music was what you did - too expensive to consume. Then for most of my 20s I studied at night after working guts out all day. There was pop music on the AM radio if you had one. I didn't get a TV until I was 28. Didn't last long, and televised pop music was just atrocious noise made by gits who didn't know what real work was. Live concerts were good, maybe I went to 2 during a decade, always high expense for something you cannot touch or keep. I still get by with so little of everything.
I get more joy now on a bicycle. No need for a back seat, shielas have all dried up 20 years ago. I quite enjoy the puzzle of a schematic when I see one or draw one, and now very much enjoy classical music. The Brandenburg Orchestra has put out an amazing number of CDs. Just pick any one and play it over dinner with glass of red. Fantastibulous!
Patrick Turner.

[mick]

On Mon, 21 Jul 2014 03:33:50 -0700, Patrick Turner wrote:

Thanks Patrick! A good read as usual.
I'm not sure that Phil's website is still there. I couldn't find it,
even by changing the spelling etc.

Gee, I would have thought Phil would have so much pride in what he
thinks that he'd have to have a website of his own that was maintained
properly, and one to give piles and piles of info about Quad-II and tube
audio in general. Alas, there is no website. You'll just have to forgive
me for typing my sarcastic hope that Phil would have had the website I
mentioned. I have "sensus humarius warperiae". The reality is that Our
Dear Phil has yet to get around to carefully crafting his own website
which would then show an enormous pile of useful stuff about tube audio.


After Phil posted I re-read your post. I fell for that hook, line &
sinker didn't I? lol . You're forgiven. I should have caught on!

But he does have published articles at the westhost.com addresses.

I've spent many a happy hour looking through that site in the past and
got some good info from it. I had a look at Phil's stuff and I think
I've glanced through it before but I'm not sure.

[[email protected]]

Patrick Turner wrote:

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... (snip)

Well I think you are half right there, even though unnecessarily pessimistic. There are lots of amateurs starting out and the simple blogs and "picture howtos" are useful to get a beginning. But then there are also great collections like this, that takes a bit longer to get through:

http://www.tubebooks.org/technical_books_online.htm

When I first got interested in restoring and building tube audio in the late 90s, I learned so much by going through the RAT archives and various homepages (mostly gone now, though). Armed with that, and my highschool maths and physics, it was (and still is) a fun learning slope to get sound and then (wow!) GOOD sound out of various old surplus tubes and transformers. But I eventually did get the books too, including RDH4.

I work a lot in teaching today and it is sad how few young people I see actually take the time to read long books when there are shorter and simpler sources of information (and gossip) that they can find online. I think this will be a growing problem in the future. But I still think books are the more longlasting medium and well worth writing.

Martin

[Patrick Turner]

Patrick Turner wrote:

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... (snip)

Well I think you are half right there, even though unnecessarily pessimistic. There are lots of amateurs starting out and the simple blogs and "picture howtos" are useful to get a beginning. But then there are also great collections like this, that takes a bit longer to get through:

http://www.tubebooks.org/technical_books_online.htm

When I first got interested in restoring and building tube audio in the late 90s, I learned so much by going through the RAT archives and various homepages (mostly gone now, though). Armed with that, and my highschool maths and physics, it was (and still is) a fun learning slope to get sound and then (wow!) GOOD sound out of various old surplus tubes and transformers. But I eventually did get the books too, including RDH4.

I work a lot in teaching today and it is sad how few young people I see actually take the time to read long books when there are shorter and simpler sources of information (and gossip) that they can find online. I think this will be a growing problem in the future. But I still think books are the more longlasting medium and well worth writing.
Martin

The trouble is that ppl start wanting an amp without wanting to be bored by learning that will only be used once. They see what is possible at home and charge ahead because it avoids the high retail prices, but all the while feeling they must get it done by lunchtime because they have terrible trouble being their own servant and being a husband and father and earning a living.

But RDH4 has excellent advice in many areas of audio. Each and every sentence is carefully crafted to contain as much info as possible, so anyone reading it and implementing schematics needs to read more than just the bits about complete amplifiers etc. All the basics need to be understood, but that takes time and nobody wants to learn.
But RDH4 amp schematics are all a bit out of date. You can do so much better that amps described in RDH4. Many bloaks aged about 80 or over tend to think there can be no improvements on sacred RDH4 texts, and its like they enjoy being stuck in the past when they were young and invincible, and rather stupid just like all the youth of all generations.

Last night I watched a show on TV about complete restoration of a 1952 Mk-1 Land Rover. Not a bad version of a Jeep :-). Not a bad item whichever way you appraise it. But really only best in the very rough. A bunch of guys did the work which took many weeks and must have cost maybe $30,000. Everything was kept exactly standard, using 1952 techniques and a few very old giza experts, so no mods, and mods to something like that is sacrelidge, plus mods start a string of related changes that easily double restoration costs. Can better be done? sure can, but costs. But I guess ppl could fit better seats, a radio, and make life slightly more comfy.

We think we are smart in 2014. But nobody has 3D printed an old Landy - yet - or a Quad-II.
And if I wanted something simple and cheap like a simple electric car, I can't have it because of add-ons and crap, and they are more expensive, so when ppl aim for simplicity now, its marketing suicide.
Much of the world has gone soft in the head about priorities.

But petrol prices can only rise.

In future, maybe 20 years, the whole motor industry will go electric, and electric cars will get cheaper, and solar and wind will take over from dinosaur coal power stations, we can charge the car batteries or those used for class A amps all so cheaply. Maybe digital PWM amps become listenable. Seems some of the digital sources are better than ever before.
Patrick Turner.