The Time Has Come (the Walrus said) Archives

Is the curse of tipping spreading?

I was going through the credit card slips doing the monthly reconciliation against the bank statement, and found one that left me wondering… is the American curse of tipping spreading to Australia?

The credit card slip was from a clothing shop. It had a space on it for a TIP to be written in.

I *know* many restaurants are now doing this and I make a point of never writing a tip in. But clothes shops?

They have to get the credit card machine program set up to do this, its not as if it’s an accident.

How obscene. I dearly hope this won’t take off.

Figs

I did this the other day. I think I nicked it from Jamie Oliver.

  • 2 fresh green figs per person
  • balsamic vinegar
  • olive oil
  • grated parmesan

Cut the figs from the top down almost completely to the bottom, as though you are cutting them in quarters (ie 2 cuts down from the top).
Push the fleshy bottom of the each quarter down onto a plate so that the top opens out.

Sprinkle on a little balsamic vinegar and olive oil (about 1/2 teaspoon each fig), and shave over some parmesan cheese.

Eat this with a main meal as a salad. Mmmmmmm….

Don’t bother unless you can get good fresh figs.

Selling yourself

I seem to have more and more CV’s coming across my desk these days.

So, job applicants, bear in mind that any busy person getting a CV they will devote AT MOST 5 minutes to looking at it. In that time you, the writer of the CV, need to make a favourable impression.

The favourable impression is what gets your CV noticed, and ANOTHER 5 minutes devoted to really looking at it.

I’ve thrown a bunch of CVs recently because the writers have just plain PISSED ME OFF.

There are two things that drive me mad:

1. Referees available on request.

2. Graduates who do not include an academic transcript.

Here’s why:

Referees available on request is playing a game. It means that I, as the recipient of the CV, have to devote anything from 10 minutes to an hour (depending on company HR policy and availability of the applicant) to trying to get the names and phone numbers of somebody to call.

Sorry chaps, you are NOT GOING TO WASTE that much of my time.

If you cannot provide the names and phone numbers of referees in the CV, don’t even bother sending it in.

It gives the impression you have something to hide, and it wastes the time of the person reading it.

It you are as good as you think you are, and you really want a job, then give ALL of the information you can and make the llife of the reader as painless as possible.

If you dont, YOU’VE FAILED. GOODBYE.

Next, graduates.

Graduates are difficult to employ. There is pretty much no employment record (at least not that is relevant) to check. Referees can really only give a character reference.

So what do we look for? Hobbies or interests relevant to the employement. Evidence of having done some homework about the employer, and (tah-dah) academic results.

Graduates include those up to a year out from their studies. The academic transcript might not show exactly how clever you are, but it does give some idea of whether you are truly a dunce or not. I’ve employed some very good people with mediocre academic results. It does not count for everything, it’s just more information.
If you don’t include the academic transcript, then we need to ask for it. It we need to ask, it’s just like the lack of referees above. You are wasting our time. You failed. Goodbye.

——

So job applicants, include as much relevant information as possible. Sell yourself, not with bullshit, but with information.

Make you work life, your achievements, your results, your history an open book. Make it brief and to-the-point. Make it easy to verify.

Then you might get a 2nd look.

And then you might make the first interview.

Spielberg would be pleased

I was at the Adelaide Central Market the other day, and took the “travelator” up from the arcade level to the car park.

At the top, proudly displayed in steel on the grate was the name of the maker: “Schindler”.

That’s why I think Spielberg would like it: It’s Schindlers Lift.

Yes, I know, it’s a lousy joke.

Coconut Chilli Chicken

After a trip to the market we had all these wonderful things lying about. Wondering what to cook, I made this up. I’d happily pay quite a bit for this if eating out. The family liked it so much that every plate was polished.

2 chicken breasts, cut into strips about 2 cm wide

1 clove garlic, finely chopped

1 small red chilli, finely chopped

1 cm piece ginger, finely chopped

About 1 cup coconut cream*

Juice of 2 limes

1-2 tablespoons sun-dried tomato cut into thin strips

About 8-10 green beans, cut into pieces about 2 cm long

About 6-10 snow peas

2-3 basil leaves

˝ handful coriander leaves

In a heavy pan, fry the chicken in a little olive oil until golden.

Push the chicken to the side of the pan, reduce the heat, add the garlic, chilli and ginger. Add a little more olive oil if needed. Cook for 1-2 minutes.

Add the coconut cream, lime juice, tomato pieces and beans. Mix well and stir through the chicken. Cook until the coconut cream is getting very thick – at least 2 minutes.

Tear the snow peas into 2-3 pieces each and add. Cut the beans into pieces about 2-3 cm long and add as well. Cook for about a minute. Tear the basil and coriander leaves into small pieces and add also. Turn off the heat, and stir through.

Serve immediately with a tossed salad, preferably dressed with lime juice, olive oil and a tiny bit of honey.

* coconut cream made from the powder, reconstituted with water, works fine.

Howard Didn’t Know

This came in the email today. I’ve no idea who the author is (so apologise for not attributing you, whoever you are.)

Just brilliant:

HOWARD DIDN’T KNOW -With apologies to Banjo Paterson.

I had written him a letter which I had, for want of better
Knowledge, sent to where I met him at the wheat board, years ago
He was chairman when I knew him, so I sent the letter to him
Just on spec, to make the point, that “Howard doesn’t want to know”.

And an email came directed, not entirely unexpected
(And I think the same was written in some Middle Eastern bar)
‘Twas his CEO who wrote it, and verbatim I will quote it,
“Trevor Flugge’s gone to Baghdad and we don’t know where he are.

But when he left Australia, he was going to meet with Alia,
A trucking mob in Jordan, who were keen to grease the wheels
For 10 per cent commission, they could swing Saddam’s permission
To get our wheat accepted: it’s the mother of all deals.

But I guarantee, Prime Minister, that there’s nothing at all sinister:
The chaps at DFAT told us that the sums looked quite okay.
When you’re selling wheat in billions, what’s a quick 300 million?
If it keeps the Nationals happy it’s a tiny price to pay.”

Sitting here at Kirribilli, I’ve been thinking, willy nilly
That it’s somehow reminiscent of the children overboard:
But I can handle Rudd and Beazley as I always do, quite easily,
By endlessly protesting that there’s nothing untoward.

I’ll tell Bush next time I meet him at
The White House, when I greet him,
That I’m sure he’ll understand about the wheat board’s quid pro quo:
He’ll forgive this minor error in the global war on terror
When I look him in the eye and tell him Howard didn’t know.

Why we like Nick X

Election result:

Liberals down a heap

Labor up a heap

Nick X returned to upper house along with an off-sider.

—-

Some good and bad out of the election result:

The good: We’ve got rid of some of the more boat-anchor Liberals. No names, to avoid defamation actions!

The bad: We did not get rid of some of the Labor dead-wood. No names again. Just my local member as an example.

The more bad: Now Labor has a big majority. Big majorities are bad, because the pollies get fat, lazy and arrogant.

The not so bad: At least Karlene Maywald (leader of the National Party!) is still in the government, as is the independent Rory McEwen. These two will help to moderate some of the more raving loony elements of Labor.

But why do we like Nick X? An independent, self proclaimed ratbag and media-tart stunt man. Because he speaks from his conscience, is not bound to a party line, and keeps the other rotters on their toes.

More of the same please, Nick.

Livin’ in a Vacuum

The average lifetime of a vacuum cleaner is supposed to be 8 years.

We’ve just bought our 3rd in 19 years which means we’ve been beating the average, so far.

I still think of the first one I bought, way back in 1986, as my new vacuum cleaner. At the time it was very expensive, top of the range, a big name brand. I paid extra for one of those turbo carpet smasher head thingies. It always seemed to work fairly well. The carpet smasher was separately powered and had a bunch of little plastic clips to hold the power cord onto the handle.

Over the years, old #1 had various things go wrong. The handle / wand thing came in sections, joined by these neat plastic clips which broke when you dropped them. But spares were available for a decent price. The wheels would wear and fall off, but we could get spares for those as well.

I used to abuse old #1 in all sorts of ways – sucking up brick dust when drilling holes in a wall with the hammer-drill, cleaning the car, and so on. The bags and filter would clog, but that was normal. The filter could be washed and had to be replaced when too daggy. And bags… changing bags was normal, but it had a nice big bag so that was not needed too often.

Finally, #1 was relegated to the workshop. The carpet smasher was a pain to take off and put on because of that separate power cord, and having the wheels constantly fall off was driving us mad.

——-

Thus came #2. Another big-name brand, different to #1. Not cheap – a middle of the range kind of price, in a nice funky blue colour. We bought him in 2002.

#2 did not have a carpet smasher, but we thought we could live without that. #2 only took smaller bags, and we could always tell when a bag needed to be replaced because the suction pretty much disappeared.

#2 suffered the same use and abuse as #1 – getting its regular share of sucking up grot in the garage, cleaning out cars, sucking up plaster dust when I’ve been drilling holes in walls.

Poor #2 suffered a calamity about a year ago. I was stirred into action by the oldest son, who told me the garage roller doors had all this dirt and crud on. An accumulation of 15 years worth, to be exact. Washing it off would just make mud and take ages, so I cleverly decided to vacuum it up. Now this dust was VERY fine, and a nice brown colour, the sort of airborne muck that lands everywhere for everyone, that most of us ignore…

All was going well, #2 was doing a lovely job slurping up that dust. The garage roller doors looked a different colour, and I was about 2/3 the way through. #2 was suffering, but labouring bravely on.

Suddenly, poor #2 could take it no more. In a fit of clogged-bag rage, he exploded with a huge cloud of brown dust. Of course, in his desire for retribution he’d expelled this all over me – teaching me my lesson: Change the bag… change the bag!

Too late, though. The bag was so clogged it had burst, spreading its load of muck through the motor and all the internal air pathways. #2 had dusty innards.

Not one to be deterred, I took #2 apart and spent a happy weekend stripping him down and giving him a service he would never forget. All those inside bits… washed and scrubbed and left to dry. Re-assembled he no longer threw clouds of brown dust everywhere. But poor #2 has never been the same. The experience left him with less suck, and a nasty high pitched whine.

———

The time had finally come. Time to buy a REAL vacuum cleaner. One that can take the use and abuse.

After mumbling about it for weeks, we’ve finally bought a Dyson bagless, the DC08 Telescope. The most expensive vacuum cleaner we’ve ever owned. But he comes with a hard floor brush, and a carpet smasher turbo head. In real dollar terms, old #1 would have cost quite a lot more.

DSCN0485.JPG

Today I put Mr D to the test. Not only does the carpet look noticeably cleaner, there is a vast amount of suck.

So, what the heck, it was time to get serious. Out to the garage. Time to clean the cars, and, just for the hell of it, suck up a bit of that fine dust that so troubled #2. After all, Mr D is supposed to be so much better than everything else, so why not abuse a brand spanking new one and try it?

After an hour of fiddling about, the conclusion is that Mr D is FAR SUPERIOR to anything that has come before. #1 and #2 are but pale shadows by comparison.

Not only does Mr D genuinely have no bag, it really does work, and exceptionally well. The very fine dust particles are separated, just as the maker claims, there is no loss of suck as the dust container fills, and everything just works.

Some of the features of the Dyson that really make it stand out:

- It really enormously sucks (sorry – could not resist)

- All the little attachment doodad thingies attach to the body of the machine, and don’t fall off! (Compare #1 and #2!!)

- The carpet smasher attachment needs no separate power at all. It runs the carpet smasher using a turbine in the air path. I was sceptical, but it works, and very very well:

DSCN0486.JPG

- It has very big wheels, which lets it drag around effortlessly

- The dust container unclips and empties very easily and re-attaches with no effort. It is a simple mechanism, very well designed.

- It also comes in funky colours, clear, steel grey and purple!

- It’s light.

I’m a convert. James Dyson sells his own story very well, and that always makes me sceptical. But there is nothing else like this, it’s simple, no bags, easy to use, easy to empty the dust, loads of suck, it just works.

Now, what to do with #1 and #2?

I feel like Angela Throgmorton, with a cupboard full of vacuum cleaners… now which one shall I use today?

————

Angela Throgmorton was the owner of Old Tom in a children’s cartoon TV series. In one episode, she has trouble deciding which from her cupboard full of vacuum cleaners to use. She finally selects “old faithful”, which goes on to break, with interesting consequences…

When the kids were smaller I made sure I never missed an episode. “Old Tom” makes good viewing for adults as well as children!

C’wealth Games opening

Just finished watching the opening of the Commonwealth Games.

I’ve a vested interest. My employer makes some of the equipment used in the building infrastructure of the MCG, so I wondered what the performance would be like. Of course, none of my employers equipment was on any kind of public show but I was curious nevertheless. If it had not been for that I probably would not have bothered.

The first half with the flying tram and the most peculiar duck was very odd. I wanted to cringe. It seemed to be a nightmare merge of the gay & lesbian mardi-gras meets Blinky-Bill. What were they thinking?

It sort of improved after that.

Tip top salad dressing

Try this… all quantities are approximate:

  • 3 tablespoons olive oil
  • juice of 3 limes
  • a small red chilli, finely chopped
  • about 1 cm piece of ginger, finely chopped
  • 1/2 teaspoon Dijon mustard

Mix these all up together about 2-3 hours before salad-making and serving time. Whisk well (a fork will do), and leave to stand. make sure it is in a glass cup or dish or similar.

When you want to use it, strain out the ginger and chilli, and whisk up the olive oil/mustard/lime juice again, then pour over your salad and toss well.

The ginger and chilli give a nice ZING! Removing them means you don’t get a big surprise in the middle of a hunk of lettuce or tomator or whatever.

The end is in sight (thank heavens)

Less than a week to go until polling day, and the State Election will be out of the way for another 4 years.

THANK GOODNESS.

I’m so fed up with posturing politicians and stupid promises.

“Trust me, I’ll spend $945 million on your pork-barrelling, whilst simultaneously cutting taxes, giving more grants, sacking loads of public servants, and employing more public servants for mental health and police officers and BLAH BLAH BLAH…”

and:

“Trust me, I’ll spend a load of your money cutting taxes whilst getting more tax revenue, and I’ll be tough tough tough on law-N-order whilst not building more prisons and not BLAH BLAH BLAH”

All those posters will soon be gone. Yay!

All those inane TV ads – gone! Yay!

All those stupid interviews – gone! Yeah!

All those loopy promises – gone! Yes!!!!

All those mindless attacks on their opponents – reduced. Groan.

OK, so maybe its the bit of quadrennial craziness we go through in the name of democracy. I suppose I should be grateful. Things could be worse. Nobody is getting killed, its a generally peaceful society, and when these turkeys piss us off enough we vote the other way and tip them out on their ear.

Yep, it might drive me mad, but it could be a LOT worse.

Appalling Stupidity

I cannot believe the local Liberal Party.

Their two latest vote-buying stunts:

Another First-Home Buyers Bribe.

An extra first-home buyers grant of $3000.

This on top of the Federal Government grant of $7000.

What a blantant bribe to young folks desperately trying to figure out how to buy their dream McMansions.

All this will do is create another property market distortion and generally push house prices up even more.

More Money for Private Schooling.

Not content with the vast amount of Federal Government money going to private schools, the local SAMWLs* want to given them even more!

You will notice that in spite of the (now) VAST amounts of government money GIVEN to private schooling, the fees never go down.

The sector does seem to be doing a power of good to the building trades though.

The amount of demolition and new building works at private schools has to be seen to be believed.

Out in the deep north where I live, the state schools have not had money spent on them for years, and it shows. Why don’t the glorious idiots of the Liberal Party go for a drive around and look at the run-down state of the government schools in Elizabeth Vale, Salisbury, Paralowie, etc etc etc etc.

Spend a few bob on the government schools, and maybe the drift to private schools will cease. But oh no, we have to privatise everything because of idiologically driven silliness. This includes education, where the taxpayers money is used to fund an endless building cycle.

Lunacy.

—–

*SAMWL – Stone-Age Mutant Whinging Liberal

—–

In case of accusations of bias: I’m not very happy with Labor either. i’m sick of their stupid ads attacking Rob Kerin. I’m sick of hearing that “Rann gets results”. I’m sick of their in-yer-face posters everywhere I look.

Arrrggghhhh!

Quad ESL-63 Repair – Ch 7 (final)

Fabric replacement

Along the way, the outer black fabric got damaged (it was a bit moth-eaten when we started), so next step was to remove the electronics at the bottom to get the fabric off.

Here is the inside of the electronics, with the delay line assemblies at the bottom:
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A quick burst by Mum on the sewing machine made up a new cover, and we could re-assemble the base, fit the dust covers, and test it again:

DSCN0468.JPG

All’s well!

Final assembly

Re-fit the grilles, roll up the fabric, re-fit the top decorative plate and it’s all done.

Here is the finished result:

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The complete rebuild and refurb took place over about 5 weekends (usually one 1/2 to 1 day per weekend).

Finished Result

Both ESL-63’s, refurbished (one with a bigger rebuild than the other), back at their home and in use again:

DSC00481.jpg

All ready now for another 20 years of service.

Quad ESL-63 Repair – Ch 6

Preventative Maintenance

Predictably enough, a vast amount of time had to be spent going over all of the panels with diaphragms that are OK, and re-glueing the stators. This is slow and painful, using a strong polyurethane glue and a paint brush.

This shows part of the re-glued area on the right hand side:
DSCN0427.JPG

First testing!

After all this fun and excitement – with a limited amount able to be done each weekend, it was time for re-assembly and testing.

The bottom two panels can be put in, and the wiring soldered up. Instead of trying to re-do the heat staking, we used a modern silicon sealant/adhesive to tack the wires in place:
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A brief test at this stage showed no arcing, and everything works OK and sounds fantastic. Time to reassemble the remaining panels:

DSCN0453.JPG

Next.. the fabric…

Quad ESL-63 Repair – Ch 5

Continued.

Making a new diaphragm.

Making a new diaphragm starts by marking the outline of the mounting frame on a sheet of glass, then laying a new sheet of Mylar over it. The Mylar comes on a roll, and is VERY thin (3.8 micron). As we found to our cost, cutting it with scissors doesn’t work! We should have read the instructions properly because when we did what it says – cutting with a hot soldering iron works a treat.

Once the piece of Mylar film is about the right size, masking tape is applied around the four sides to prevent tiny imperfections causing a tear during tensioning (this we worked out after 3 failed attempts, and a phone call to Ron McKinlay).

The Mylar is then tensioned to 2.4 kg using very strong fabric reinforced tape and a spring balance. Many pieces of tape are needed, the whole process of tensioning takes about an hour.

This shows just after we started:
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DSCN0451.JPG
After tensioning and priming, the cleaned up frame has a generous coating of Cyanoacrylate glue applied, and is pushed down onto the tensioned Mylar. Apply a LOT of weight (a big board, a carton of wine, some tins of paint and a few power tools). Leave for 24 hours.

Once the glue is cured the weights are all removed and the excess Mylar is cut away from all that black tape, again using a hot soldering iron. Then the edges are carefully sanded back to make it neat and trim.

Next, the special conductive coating is applied. This new modern stuff is clear, unlike the original grey. Making the holes for the screws is a nervous moment, but again the hot soldering iron works a treat. We don’t want anything going wrong at this stage, because the Mylar is under so much tension that the tiniest nick causes a big tear – almost like an explosion.

The newly coated diaphragm looks like this:
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To be continued…

Quad ESL-63 Repair – Ch 4

Continued from Ch 3.
Taking apart the panel unit.

Taking the panel apart is easy – 3 screws and a few clips. Care needs to be taken to avoid damaging the Mylar film which is the diaphragm – it is the grey coated thing below:

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Typical damage – a small cut or tear. The spotting appears to be normal.
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When a diaphragm is damaged, there is only one option. Remove it, clean up the frame, and make a new one.

Removal is easy – the Mylar is so thin it tears off easily. But it is glued onto the frame around the edges, and cleaning off the old glue and mylar is slow and laborious. Scraping with a not-too-sharp knife seems to work.

Next… making a new diaphragm.

Quad ESL-63 Repair – Ch 3

Continues from Ch 2.

Next step is to take apart the frame holding the panels in place and start to remove each panel, one at a time, working down from the top. In our case we had to repair the panel at the bottom, and inspect all the others for damage on the way. Each is held to the frame assembly with 4 screws – one in each corner:

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During the disassembly, the panel interconnect wiring needs to be desoldered and removed (and kept for later re-assembly):

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The bottom two panels have all of the signal wires that come up from the electronics underneath. These are soldered and heat-staked in place. Removing them is difficult – it is easier to cut them and solder up later (not a very good photo):

DSCN0443.JPG

Each panel needed to be taken apart to inspect the diaphragm for damage – burns, arc marks, holes, etc. That will appear in the next exciting installment.

Quad ESL-63 Repair – Ch 2

Continued from Ch 1…

Refurbishing

Here are some pictures and a bit of a commentary about the rebuild of one of the speakers. In this case we had a bass panel that was sparking and it just had to be the one at the bottom, requiring a complete dis-assembly, strip down and rebuild.

Disassembly

Taking the unit apart (at first) is fairly straightworward when you know where to start. The instructions from ER Audio were very helpful.

After removing the decorative piece of timber at the top, the black cloth is rolled down to the bottom out of the way. Then the front and rear grilles are removed, showing the transparent dust covers in front of the electro-static panels:

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Next, the dust covers are removed. These have a neat clip-in arrangement to the aluminium structure, so they just lever off. They are like a large sheet of glad-wrap on a frame, so they need to be handled carefully.

This leaves the electrostatic panels exposed:

DSCN0426.JPG

On this view you can see the concentric anodes of the treble/mid range panels. These are driven by delay lines, which makes the sound appear to come from a point source about 3 feet behind the unit. The green part is a (coated) copper layer over a printed-circuit-board-like substrate materal. This is the part that runs at 5000 volts. The holes let the sound out.

DSCN0428.JPG

Those big circuit-board like panels (the stators) are glued onto the plastic frame, and when the glue fails, the stators can flap around and move closer to each other. This is very common at each end.

Continued in Ch 3.

Quad ESL-63 Repair – Ch 1

My father and I have just finished the repair and refurbishment of a pair of Quad ESL-63 electrostatic loudspeakers.

(And no, Quad is NOT quadraphonic, it’s the name of the company that makes them.)

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A bit of Background

The ESL-63 first went into production in about 1982 or 1983, and ceased some time in the 1990’s. They are still regarded as one the best loudspeakers ever manufactured.

There is a vast amount of information on the net about the ESL-57 and its successor the ESL-63.

Why the name ESL-63? ESL just stands for Electro Static Loudspeaker. The 63 is because that is when the design work began. Peter Walker, the chief designer, was a genius who spent the best part of the next 15 years perfecting this design before it eventually entered production.

An electrostatic speaker works by moving a very thin, light, conductive diaphragm between two highly electrically charged plates. This presents a few obvious problems for manufacture:

- how do you generate the voltage (typically 5000V)?

- how do you couple the audio signal from your amplifier onto those charged plates?

- how do you get the sound out?

- how do you keep the highly charged plates from attracting dust and grot?

These problems were all solved with the first Quad ESL speaker back in about 1957.

The next generation, though, uses delay lines and other clever things to make the sound appear to be coming from a point source behind the speaker.

To quote from the Quad web site:

The ESLs work in a very different way to conventional loudspeakers. For those who don’t know, here’s a brief explanation of the principle. Whilst most speakers work with a cone type drive unit, the ESLs use a very thin membrane, one-tenth the thickness of a human hair. This MYLAR diaphragm has a special conductive coating and is stretched between two electrode plates. Relative to earth, both electrode plates have a high positive charge (+5000v), but there is a slight difference between the charge on each electrode. It is this difference that causes the negatively charged membrane to be more attracted to one than another, thus causing the movement of the diaphragm.

The diaphragm is mounted on an open frame and is thus free of any coloration from a cabinet. Because the diaphragm acts as a full range driver, there is no need for a crossover. There are no discontinuities in the frequency response curve, so you get the full music spectrum, as it was recorded.

The ESLs do much more than reproduce the full range – and this is where all other electrostatic speakers stop. Acousticians have recognised for a long time that an ideal loudspeaker should be a point source from which sounds waves ripple like a pebble in a lake. Ordinarily, an electrostatic would fall at this hurdle, but not the QUAD ESLs.

By using a series of concentric anodes, rather than just two plates, the Quads are able to produce a spherical sound pressure pattern. A series of electrode rings are fed with delay lines, so each ring responds to the change in current a split second after the previous ring, creating movement in the diaphragm identical to the ‘ripple in the pond’.

Failures, rebuilding and spare parts

Unfortunately, there are a few manufacturing quirks that come to bite an electrostatic speaker that’s 20 years old.

The major cause of failure is the glue used on the frame arrangement used to mount the stator plates and diaphragm. The high voltages and ionisation of air attacks the glue and over the years it becomes brittle and fails.

When the glue fails, the stator plates can move, and if they move too close to the conductive diaphragm (or to each other) it leads to arcs and sparks. They are not known to catch fire, but it doesn’t sound nice and it looks bad in a darkened room!

In Dads case we had one speaker that failed and needed to be repaired. Within days of that one being rebuilt, the other one went the same way.

Fortunately, Rob at ER Audio in Western Australia has a wealth of repair information available, and sells kits that let anybody with a decent workshop do a detailed rebuild. When there is a major screw-up, spare parts can still be bought from Quad Germany or (in some case) the Quad factory in England.

Stay tuned for the next exciting installment!

Free vs. Pedantic Thinking

Another one thanks to David (who should set up his own Blog!)

The following piece by Alexander Calandra appeared
first in The Saturday Review (December 21, 1968, p 60)
It was discovered in a collection More Random Walks in Science
by R. L. Weber, The Institute of Physics, 1982.

Some time ago I received a call from a colleague who asked if I would be the referee on the grading of an examination question. He was about to give a student a zero for his answer to a physics question, while the student claimed he should receive a perfect score and would if the system were not set up against the student. The instructor and the student agreed to an impartial arbiter, and I was selected.

I went to my colleague’s office and read the examination question: ‘Show how it is possible to determine the height of a tall building with the aid of a barometer.’

The student had answered: ‘Take the barometer to the top of the building, attach a long rope to it, lower the barometer to the street, and then bring it up, measuring the length of rope. The length of the rope is the height of the building.’

I pointed out that the student really had a strong case for full credit, since he had answered the question completely and correctly. On the other hand, if full credit were given, it could well contribute to a high grade for the student in his physics course. A high grade is supposed to certify competence in physics, but the answer did not confirm this. I suggested that the student have another try at answering the question. I was not surprised that my colleague agreed, but I was surprised that the student did.

I gave the student six minutes to answer the question, with the warning that his answer should show some knowledge of physics. At the end of five minutes, he had not written anything. I asked if he wished to give up, but he said no. He had many answers to the problem; he was just thinking of the best one. I excused myself for interrupting him, and asked him to please go on. In the next minute he dashed off his answer which read:

‘Take the barometer to the top of the building and lean over the edge of the roof. Drop the barometer, timing its fall with a stopwatch. Then, using the formula S = at2/2, calculate the height of the building.’

At this point, I asked my colleague if he would give up. He conceded, and I gave the student almost full credit.

On leaving my colleague’s office, I recalled that the student had said he had other answers to the problem so I asked him what they were. ‘Oh, yes’ said the student. ‘There are many ways of getting the height of a tall building with the aid of a barometer. For example, you could take the barometer out on a sunny day and measure the height of the barometer, the length of its shadow, and the length of the shadow of the building, and by the use of simple proportion, determine the height of the building.’

‘Fine’ I said. ‘And the others?’

‘Yes’ said the student. ‘There is a very basic measurement method that you will like. In this method, you take the barometer and begin to walk up the stairs. As you climb the stairs, you mark off the length of the barometer along the wall. You then count the number of marks, and this will give the height of the building in barometer units. A very direct method.

‘Of course, if you want a more sophisticated method, you can tie the barometer to the end of a string, swing it as a pendulum, and determine the value of ‘g’ at the street level and at the top of the building. From the difference between the two values of ‘g’, the height of the building can, in principle, be calculated.

‘Finally,’ he concluded ‘there are many other ways of solving the problem. Probably the best’ he said ‘is to take the barometer to the basement and knock on the superintendent’s door. When the superintendent answers, you speak to him as follows: “Mr Superintendent, here I have a fine barometer. If you will tell me the height of this building, I will give you this barometer.”‘

At this point, I asked the student if he really did not know the conventional answer to this question. He admitted that he did, but said that he was fed up with high school and college instructors trying to teach him how to think, to use the ’scientific method’, and to explore the deep inner logic of the subject in a pedantic way, as is often done in the new mathematics, rather than teaching him the structure of the subject. With this in mind, he decided to revive scholasticism as an academic lark to challenge the Sputnik-panicked classrooms of America.

McMansions

Erk, how hideous. Read the transcript of a story about those awful, enormous houses that we see going up everywhere.

“Look at me – I’ve got more money (or a bigger mortgage) than you, so shove that in yer pipe and smoke it.”

What happened to egalitarian Australia?

We’ve become a nation of fat, lazy, monster-house-owning endlessly-polluting selfish nutcases.

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