Sound Quality Vs. Measurements

[abraxalito]

Originally Posted by dvv

Agreeing with something is a religion?

Nope, I was remarking on your use of the word 'believe'.

Well, I did post a working model proposal right her - but I never saw anything specific in that nature that you posted?

You posted up where Bob Cordell was mistaken in his reasoning about OLBW? Please point me there, I missed it.

[scott wurcer]

Originally Posted by dvv

I honestly believe Otala, and by extension John, are right. I do not expect other people to believe it, if they so choose, and will never think less of them because we don't agree. Wahab, for example, who is known by his choosing not to agree with Otala's theories, is no less respectable for me just because we disagree on this one point.

Its not a mater of belief, it's taking someone's work and claiming it is a technical proof of their theories. The particular connection between high open loop BW and distortion as stated is provably wrong, Bob Cordell has done it and so did that link I posted. If you build amps according to Otala's rules and subjectivly like them that is a different thing.

[a.wayne]

Originally Posted by dvv

It was better than that, Wayne. I came to ye olde England in September 1967, and started my grammar school (high school) education there. At the time, the system required you to pass O (ordinary) level exams after two years, and then A (Advanced) levels after the other two years.

Your choice of subjects at both O and especially A levels determined your chances of enrolling at a university of your choice, as per the list of requirements each one of them had.

So, in 1969, I passed my own seven O levels, and much to the surprise of my English teacher, actually got a grade 3 in English language. Official O level diplomas carried no grade then, but the initial notice did have the marks. It turned out he was uncertain I'd even pass, and I not only passed, but got a very high grade (grade 6 was a pass, grade 1 was as rare as wisdom teeth), and my British friends scraped by with grade 5 being the best.

Next, I enrolled for the A level courses, did the first year, but went back home to Yugoslavia in July 1970, as my dad's tour with UNESCO was over. This turned out to be most fortunate for many reasons, but that's a long and very convoluted story up Alfred Hitchkok's alley.

Then dad went on to complete his work for the UN in Cairo, Egypt, leaving me to study at home and visit every three months or so. So, just for a change, I was allowed to actually complete my university studies in one, straigh run, with no funnies in between. Sometimes, it's just great doing things the plain vanilla way.

Americans. You Americans are actually resposnible for teaching me just how relative things can be, and often are. When dad first started working for the UN, his first post was Ankara, Turkey, where he taught meachine elements, probably the hardest part of being a mechanical engineer. Mom and I joined him in February 1964. At the time, my "knowledge" of English boiled down to reciting "Twinkle, twinkle, little star" - literally. At home, we had just started learning foreign languages at school.

Then I found out that we lived in a part of Ankara which was almost all inhabited by US Air Force personnel and their families. Remember, in 1964, the Cold War was on full force. Ankara alone had an Air Force and Army population of over 30,000. So, who did I have to play with, at a tender age of 11? Americans, that's who.

Thank God I was blessed with an ear for languages, because I went from zero to hero in 3 months flat. From nothing to fluent (at that age). Half of that was sheer inborn talent, the other half hard work. I won't bore you with details, but trust me on this, February-July 1964 was the hardest part of my life, get up at 6 AM, work, work, work all day, go to bet at 10 PM, free time Saturday afternoon. I did it all, and rather well at that. But I wouldn't wish that on any child.

Believe me, you cannot even imagine the cultural gap between those kids and me. Enormous! But still doable. Without actually realizing it, or being able to vocalize it, I learnt that there is a world of difference between a country's policy and actual people behavior. Like Air Force mothers serving us kids afternoon sandwiches without bothering to even ask who's who. I was just another kid on the block, who just happened not to be US made. I even got stitches, courtesy of Uncle Sam and the Air Force, at their hospital, after my head happened to be in trajectory of a rock; Dave, the guy who threw the rock, had a very unpleanst close encounter with his dad's service belt right there, on the street. I reckon he got off worse than I did, but we still stayed friends.

As for your comment on education capabilities, don't write the US off so quickly. In 1991, I helped a professor from Babson College near Boston organize a seminar for young enterpreneurs. This resulted in a month's worth of a seminar, mostly in Boston, but also in NYC. Walk down their alumini lane and you will see some far from insignificant faces hanging on the walls, for example, people like Ken Olson (who invented Vax and established Digital as a company), Charles Wang, and so forth. True, that is very much a rich man's school, but quality is NOT an issue. Some of their concepts were, though, but hey, what's the academia to do but argue concepts?

Yep , I know about "O" and "A" levels ... I took my O Levels in 77 ......

[a.wayne]

Originally Posted by nigel pearson

Just about to start today's work and should have started . Many years ago I went to a cutting of a very famous band . Rock music with classical overtones . The cutting lathe was Scully with a SP 10 used as a motor ( not ideal if the music has pace ) . The cutting was strict analogue and a very wide dynamic range although soft sounding . Tests were done at 33 1/3 45 and 78 ( all RIAA microgrove ) . 78 was so close to the original as to defy belief ( we were doing A/B in real time , it was a test cut ). This cut was strictly to the production master and had calibration settings . The playback was via SME 12 inch and Shure . The engineer then produced a SACD to compare ( from the same tape ) . He was rather horrified when I said it sounded like a tribute band . I was shocked also as I am content with CD . In his place I would have made the CD from the acetate copies ( not DMM ) . Now that's bonkers , yet I have a hunch it will work . How we do shaping is important .

Now here is a thing .Basically analogue tape recording is a digital process . The bias frequency pushes the magnetic circuit into something that looks suspiciously like digital . So we have ways of doing things which "approximate" to the same thing . 100 kHz bias could be said to be 198 kHz sampling if you look at it . One sounds better .

I don't accept that cutting is a black art . Yes it is , however it speaks badly of an engineer who can hear every defect if vinyl yet can not get a CD to sound the same . Not least he was so proud of the CD. Many people now are getting digital removed from the laths . They are fitting old vario-matix . An analogue vario matrix 78 micro grove can be 12 minutes long .

Lets be clear I have no problem with digital . However these inconvenient truths refuse to go away .

Monitoring was Tannoy and bespoke American 1970's tube amps .

SSL now sell special effects which mimic other companies mixing desks . They apparently do well with it . The engineer David Mate is especailly gifted in knowing why things we like work and has proved it by doing this . David tried to sell some Hi Fi once . No one would even talk to him . Best speakers I ever heard were his . They had feed forward error correction and produced square waves .

Interesting take on the vinyl stuff , I'm of the same disposition , I have no problems with digital either , but I do hear what analog does so well. As for selling Hi-Fi, you have to be a member in that club , nothing to do with product, they will make it the best after acceptance ..

[nigel pearson]

Celestina Boninsegna - TOSCA (1908) - Truesound Transfers - YouTube

You will hear the impossible . If you don't understand you don't love Tosca .remember she has never been corrupted by recorded sound .

This is time travel and proves I am no digital hater .

[john curl]

Dvv, you and I both have some experience of 'what works', and we are not alone.
Bob Cordell has been 'after' Matti Otala for more than 3 decades. He likes to say that Otala was NOT first, that he made mistakes about the necessity of requiring high open loop bandwidth to remove TIM, and that Bob's measurements of PIM, which did not show much, to be the last and final nail that closed the subject.
Well, it isn't exactly all there is, and subjective listening has shown this to be true. We are working on 'objective' tests to show, in future, what we already know by listening.
However, people here will not see this work, before its time, because of the natural resistance to rebut it, out of hand. Hang in there, dvv.

[dvv]

Originally Posted by abraxalito

Nope, I was remarking on your use of the word 'believe'.

You posted up where Bob Cordell was mistaken in his reasoning about OLBW? Please point me there, I missed it.

No, I did much better than that, I psted a model of what I cinsider capable of becoming a high quality audio amplifier, designed with Otala's principles in mind.

You see, to me, the proof - or not - is in the pudding. If you do smething according to somebody's guidelines, and it ends up working well, then it's safe to assume that somebody's principles are all right when the above happens for the 11th or 12th time in an unbroken row.

And it becomes a bitch to disprove. And the bitch is all yours, Mr Cordell's and whoever else you want to call in.

[dvv]

Originally Posted by scott wurcer

Its not a mater of belief, it's taking someone's work and claiming it is a technical proof of their theories. The particular connection between high open loop BW and distortion as stated is provably wrong, Bob Cordell has done it and so did that link I posted. If you build amps according to Otala's rules and subjectivly like them that is a different thing.

(Bold and red by DVV)

Scott, that is all and precisely what I have been saying. I do not think of Prof Otala as a Higher Being, an idol or whatnot, simply as a man who walked down a certain path, came to certain conclusions and laid them out for all to see, read and make their own conclusions. I read them, thought about them and concluded that he was right - strictly in my view. You may differ.

I then proceeded to make 11 or 12 units, for various purposes (i.e. not all were power amplifiers), all of which simply convinced me beyond reasonable doubt that Prof Otala was right. Certainly not 100%, nobody is 100% right, but in essence.

Obviously, I did like what I got, or I wouldn't have kept on. Moreover, others liked it as well, so some models slod well, fetching very reasonable prices.

All of which is completely meaningless and irrelevant to you, if you should happen not to agree. We all hear things our own way. Many times I have heard units and entire system which sounded godawful to me, but their owners loved them. So what? We're still friends.

I am too old and too experienced to even think of trying to change peoples' minds, let alone try it. I do NOT understand why is it so important to some people to "prove" Otala's views wrong - if I don't agree and/or like X, I simply ingnore him altogether.

Some people like the priest, others prefer his wife.

[dvv]

Originally Posted by a.wayne

Yep , I know about "O" and "A" levels ... I took my O Levels in 77 ......

There you go, Scott. We have now earned the right to address each other as "colleague".

Although, of course, much depends on whose turf you did it, Oxford or Camebridge. Bob Stuart and I are Camebridge men.

[a.wayne]

Cambridge .....