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