Conrad's little corner of the WWW.
  • 2002 A bit of nip and tuck lately to this page to trim some of the dead links.
  • 2007-01-19 Add link to Lucy Durack. Now, I'm biased, but even Bert Newton agrees that she's one of the best new voices in Australia. And now you can hear her sing! Hear Lucy!
    Dignity
    Bread & Water
    Not For You
  • 2008-02-20 Woo-hoo Lucy is Glinda!
    The Big List of Links is here [updated 31 Jan 2001]

    CELEBRATING 15 no-20 YEARS ON THE INTERNET!

    Well, of sorts. Just means I'm getting on. From student days @ee.uwa.edu.au, ('86 - '88) the late lamented qpsx.oz.au, ('88 - '95 ? - see the ATM Forum for info on what was QPSX's work).
    Then jtec.com.au ('95? -'98), intellect.com.au ('97 - 98') and now smr.com.au ('98 -) I've finally employed myself (directwest.iinet.net.au) and now have to _pay_ for my access.

    The halycon days of the dot com boom were spent with SMR Electronics, now owned by Lateral Sands.

    2003 - Post 9/11, SARS and Enron, I moved to Raytheon and did systems engineering & various bits of engineering management. Mid 2006 I moved to Motherwell Automation, who were expanding their engineering operations.



    Audio, radio and music in general.

    DIY and my system

    Currently, badly in a state of flux. Half wayAlmost through building a modified version of Lynn Olsen's Ariel speakers. (up, running, just some of the tweaks need tidying up) Not much else happening.



    Speaking of Sage advice

    Sheldon Brown has left us.
    I'm old enough to have had many relatives and friends pass away. But the passing of this particular, very occasional correspondent has left a hole which I struggle to rationally explain.

    The thoughts of Ragnar Lian on speaker design issues. (translated by Thomas Dunker )

    Wernier Olgier's "Visions in Audio" is an interesting read.
    Frank Van Alstine gets closer to the problems of "HiFi" by making some comments on the emperor's new clothes in "If HiFi were tyres". He also talks quite a bit about cables on his site.
    Cables! Even Neville Pass has made some comments on cables.
    As have the TNT Audio crew. The first stop there is The Naked Truth about Interconnect Cables - they have lots of DIY cables recipes. Also hunt through the DjaNews rec.audio-high-end archives.

    One of the more lucid comments on cables was by Bob Stout and appeared in bass-digest.4730 after someone Xrayed an MIT cable and spotted lots of filtery bits.

    ... Perhaps the problems with cables are nothing more than RF sensitivity coupled with the non-linear point contact characteristics of the conductors. If so, then anything which degrades the cable's performance as an antenna and/or rectifier at RF frquencies is good. The root of all cable skepticism is that even gross effects in long cable runs will have a minimal effect at audio frequencies. But, what if the culprit were RF emissions (with which we're inundated in modern life) external to the system? This supposition might fit both the claims and the science.

    My take on speaker cables is that at my price point, 15A solid house wiring is very good - if very ugly. Trevor Wilson at Rage Audio had a limited supply of solid core, teflon coated copper wire which should allow a somewhat better cable, with massively better looks. After that you're into the low end commercial stuff and rapidly diminishing returns.

    But the moral of the story? Clean your connectors! Most oxides/sulphides are awefully non linear

    Audio for Art's Sake

    SNIPPED - everyone's moved.

    Oz speaker builders.

    Back to reality. The Melbourne Audio Club Inc. keeps an up to date list of these sort of things.



    Perth and Rottnest.

    Rottnest is one of the many reasons for living in Perth, Western Australia, along with the South West regions. Whether the huge distance to JFK or Heathrow is a curse or a blessing depends on your point of view:-) We are four and a bit hours from Singapore, five or so from Sydney or Melbourne and ten from Jo'berg. Jakarta is the nearest big city and Bali is a favorite holiday destination.

    Have a look at:

    Or do a WWW search on "quokka"!

    If you're here in August and it's raining too hard, the maritime museum the art gallery and the library are not bad




    X1/9

    Now sold. Shame. Currently riding most days - old Ricardo 12speed with toe clips. So
    declasse.

    My X1/9. (Yes, they're 8 slotters, not 10)


    Bikes

    While I hold D.O.D. #604 I'm still Ed Green fan club member #1. Head of to >
    micapeak for some good bike links.

    Surf

    The big link in Oz is to the swell map. Economic rationalism means that the one my tax dollars produce is not available anymore.
    Try
    Surfshop's map
    The original is (was) available as Weather-by-fax - see the BOM for this and lots more.

    Visit Lud's page too.


    radio

    Most of our commercial radio is, well like commercial radio everywhere.
    But we have a national, publicly funded broadcaster - the
    A.B.C.

    And there's a bundle of small "public" radio stations in most big cities. My favorite here is RTR FM. I used to spin disks there, organise one show and was involved in the rebirth after the university cut funding (even was a director for some time)


    Other

    Occasionally I do a little html for freinds and family
  • Table Art - hand painted ceramics.
  • Makker - Bernese Mountain Dawgs.

    I was going to do Pollock Productions but I'm pretty happy with what they got!


  • The following is a rough draft, which I'll keep working on.

    A brief history of audio amplifiers

    Below is a rough timeline of important amplifiers. One can argue that there's a bunch of important designs and designers not included (such as Marshall Leach or Tim Pavotti) but they're not here because they've not appeared as a reference against which others have regularily measured themselves. It may be that just not published or explained enough to be noticed.

    RCA

    Loftin White

    Brooks

    The proof in the pudding is that a pair of 10Cs will break $7KUS on ebay

    Williamson

    The first working feedback amplifier. The basis of a massive number of derivative works, tweaked and tuned to this day. Mr Wright

    Ten Simple Watts

    John Linley Hood's search for something as good but cheaper than the Willamson created this absolutely pivotal amplifier. Fourty years on it is still being built in droves and for good reason.

    The Muscle Era

    Sliding bias, steaming arrays of barely stable transitors, massively inefficient speakers. And dozens of dreadful sounding amps. I know, I built a bunch of them (ETI-5000 anyone?).

    Undoubtably, there's some good amps there and the sight of Krell battleships will still cause whispers of awe.

    Nelson Pass

    Always a bit of an iconoclast, his move to simple Class-A designs while everyone else was counting watts set a new way of thinking alight His constant reexamination theory and williness to share the results over thirty something years makes him a pivotal part of the history. (see this feature for more

    The Single End

    About the same time as Pass Labs was going Class-A, a bunch of people in Japan, France and New York discovered that these weird old vintage amps, speakers and turntables sounded a lot better than their figures said they should.

    And that "perfect sound forever" actually wasn't.

    JC Morrison's Fi Primer was one of a number of 'scribbled notes' which kickstarted the DIY SET revolution. By the mid ninties the counter-culture was in full swing, with the epicentre not far from Joe Robert's "Sound Practices" magazine.

    Inevitably, the collectors and snake oil salesmen moved in and "if it measures good yet sounds crap, maybe you're measureing the wrong thing" became the "I don't need to measure anything" rubbish of today's mainstream.

    Douglas Self

    Someone who's designs I've never heard or built, but his analysis of the "blameless amplifier" set a new set of design benchmarks for conventional amplifier design

    Hugh Dean

    Possibly the last of the great amateurs - the AKSA takes on all the lessons of the past. I may have missed my opportunity to build one, as Hugh seems to have taken on board some of the lessons from the next chapter

    Attack of the Gain Clones

    One of the reasons that discrete designs are threatened. The team at Nat Semi listened to the gurus (including, undoubtabley, Bob Pease) and have produced some seriously good amplifier modules, particularly the LM3875. Which were "discovered" by the serious young insects 47 Labs, repackaged and presented to a new audience. The rest, as they say, is history.

    Class D

    Just as it's taken twenty years to get a decent sounding CD player, it's going to take a while for Class D to move out of subwoofer enclosure of anything not battery powered

    what we thought we knew

    I had a very frustrating and sobering experience as an undergraduate trying to develop a new amplifier topology. According to the theory, this thing would rock. After all, feedback could fix everything. It didn't. In hindsight, it couldn't. (I should have recognised that what we were learning about nonlinear time variant control systems was applicable to mosfets and BJts as much as motors & gearboxes.

    Effective SNR in LP records

    Ragnar Lian on speakers

    The thoughts of Ragnar Lian on speaker design issues. (translated by Thomas Dunker )

    skin effect in cables

    Pass on current drive

    . someone listen'd to Ragnar See


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