A Sony' CRTs color is screwed up.

[Phil Allison]

"Jeff Liebermann"
"Phil Allison"

My simple test is explained here:
http://sound.westhost.com/absw.htm
.... Phil

Nicely done. I'm surprised that you didn't hear any pops and clicks
as the input capacitors charged and discharged when hit with random
points on the audio input waveform.

** Huh ???

Does my schem show input switching ?

And what about this bit ?

" Make "Y" leads to connect the left and right input signals to both
amplifiers."

Switching amp inputs was un-necessary and would create some audible
transients, but simply using a change-over relay to select between two
amplifiers that are producing virtually identical output signals results in
no audible transients on music or speech.

Another possibility when setting up is to connect the speakers across the
hot outputs of each amp - then adjust input levels to get the least sound.
With identical amplifiers, this should result in silence from both
peakers - which only proves the signal gains are equal as neither amp is
driving any load.



.... Phil

 

[Smarty]

On 6/6/2013 10:32 PM, Phil Allison wrote:

"Smarty"
Perhaps, but Bob Carver proved the opposite.
My recollection is that Carver nulled the difference signal between some
highly regarded amps and his own prototype, doing so in order to "voice"
his to imitate theirs. By using (again as I recall) passive reactances, he
was able to get the two transfer functions so similar that their null was
down many tens of dBs.

The outcome of all of this was that no audibly discernible differences
could be reliably reported, at least according to Carver in his claims.

This method obviously did not account for the different dynamic
characteristics of the two amps, such as output transformer saturations
and harmonic spectra / distortion changes over the dynamic range of the
amps.

** Bob Carver only ever made transistor amps - notably under the Phase
Linear and Carver brands. It is generally only tube amps that have such high
output impedances that speaker loading affects the response audibly.

Carver actually did also make tube amplifiers, and one of such series is
described here in the link below. Other tube designs by Carver were also
developed and sold.

http://www.carveraudio.com/index.php?page=shop.product_details&flypage=flypage.tpl&category_id=1&product_id=2&option=com_virtuemart&Itemid=104&vmcchk=1&Itemid=104


With regard to your comment comparing Carver amps versus tube amps and
their output transformers, I didn't particularly assume Carver's design
was solid state and the reference was not, since I have no reason to
believe this was actually his situation. The comment I previously made
was that Carver's prototype could never ***exactly**** match the
reference amp he was attempting to imitate due to differences between
the two which would not be amenable to simple transfer function /
frequency response / phase response alone. I mentioned examples of
obvious areas where such differences would still show up.

Bob's prototype in this case very well may have been solid state, and
then, to an even greater extent would fail to imitate the reference tube
amplifier, if in fact the reference amplifier was a tube design, in the
specific area of output transformer performance, for the obvious lack of
an output transformer in Bob's amp. Even if Bob was comparing his tube
design to a reference tube design, the nulling method he used would not
show their differences in dynamic performance necessarily either. His
"voicing" strategy also failed to look at intermod, and the more
complete time bandwidth differences which would have been difficult or
impossible for him to really measure years ago for nulling purposes, in
particular FIR, for which no low cost deconvolvers were out there yet. I
believe he used swept sines or possible some more harmonic-rich test
signals, but he was unlikely to have been able to do true and holistic
comparisons with finite impulses and other comprehensive methods now
considered much more common place.

* * Where an audible difference REALLY exists, there will be an easily
measured difference too. This what Bob found and figured he could
emulate with a few passives added to one of his designs. It is not
necessary to match amps so precisely to make them sound
indistinguishable in normal listening circumstances.


I agree strongly. The human hearing system is a relatively inaccurate
tool for hearing fine details which show up glaringly in some very
simple tests and measurements.

.... Phil

 

[Phil Allison]

"Smarty"

Phil Allison wrote:
"Smarty"

The outcome of all of this was that no audibly discernible differences
could be reliably reported, at least according to Carver in his claims.

This method obviously did not account for the different dynamic
characteristics of the two amps, such as output transformer saturations
and harmonic spectra / distortion changes over the dynamic range of the
amps.

** Bob Carver only ever made transistor amps - notably under the Phase
Linear and Carver brands. It is generally only tube amps that have such
high
output impedances that speaker loading affects the response audibly.

Carver actually did also make tube amplifiers, and one of such series is
described here in the link below. Other tube designs by Carver were also
developed and sold.

http://www.carveraudio.com/index.php?page=shop.product_details&flypage=flypage.tpl&category_id=1&product_id=2&option=com_virtuemart&Itemid=104&vmcchk=1&Itemid=104

** How many Silver 7s did he sell?

Was it 2 or was it 3 ??

The site covers the Silver 7t & 9t, which are a transistor amps.

The only Carver amps ever sold or advertised in Australia were transistor
models - but I see on the net he has just released some new models that
use tubes.

The comment I previously made was that Carver's prototype could never
***exactly**** match the reference amp he was attempting to imitate due to
differences between the two which would not be amenable to simple transfer
function / frequency response / phase response alone. I mentioned examples
of obvious areas where such differences would still show up.

** Hypothetically only, no way are they likely to be audible.

Bobs emulations were in terms of frequency response and output impedance -
which at least can lead to audible differences.

Bob Carver was and is a colossal bullshitter.

Take his " Magnetic Field " amp nonsense for example - purest marketing
hype and very misleading.



.... Phil

 

[micky]

On Fri, 7 Jun 2013 02:52:17 +0100, "Arfa Daily"
<arfa.daily@ntlworld.com> wrote:

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:b1ap1mF4jimU1@mid.individual.net...

"micky"
"Phil Allison"

"micky"


** FFS stop wasting your and our time.

Is the set's de-gaussing thermistor working or not ??

Don't know yet. No time or space to take it apart. Have to make
room.

Does it go * BONG * at switch on or NOT ??

No, I made a special effort to listen. Turned it on several times.
I hear a relay click, but the sound is almost the same turning it off
and turning it on.

But I don't think this tv ever went BONG, like one other did.

Odds-on it is the problem and when fixed the set will de-gauss itself.

That's added incentive to turn it around and take the back off.


** Be very careful poking about on the PCB !!!!!

Some Sony Trinitron portable sets were "live chassis" jobs.

Almost all the circuitry is at main voltage - so you need an isolation
tranny to work on them.

Thanks for the warning.

.... Phil



Agreed. If you can locate the degaussing posistor, just remove it from the
board, and shake it. Usually, a faulty one will rattle. One of the two
thermistors in it will crack or break, and then it falls to bits. This often
results in the spring tension holding the other one in place, to be
released, so that one falls loose into the case as well. They are usually
roughly the size and shape of a highlighter (pen) cap - the stubby oval
type - and can be black, white or blue, and normally have three legs.

Thanks.

Go to Google images and type "posistor" into the search field, if you are
not familiar with what they look like. There are loads of images of them on
there.

Thanks. I started doing that.

Arfa

 

[Phil Allison]

<jerk6006@gmail.com>

" just remove it from the
board, and shake it. Usually, a faulty one will rattle. "

I would fire you. All that shit to determine if something is fucking
magnetized at $30 an hour.

** You must be seriously delusional.

FACT:

Remote diagnosis with only a novice informant is a 100% mug's game.

PLUS:

WE do not even know what model it is - just a 19 inch Sony from the early
90s.

WE cannot make any observations or do any simple tests to base a diagnosis
on.

And YOU are not any help with fuckwit posts like this.

I am not trying to insult you,

** Yes you are, you love doing it.

Fuck off - stupid troll.



..... Phil

 

[William Sommerwerck]

My memory is that Bob used a transistor amplifier. (Indeed, part of the point
of the experiment was his claim that he could make a transistor amp sound like
a tube amp by approximating the latter's frequency response.) An amplifier
with an output transformer would be less "fungible".

Bob reported that at least some amplifiers' transfer characteristics varied
with line voltage. Given that transistor amplifiers generally have follower
outputs and overall feedback, this is somewhat difficult to believe, but I'm
not going to gainsay Bob.


* * Where an audible difference REALLY exists, there will be an easily
measured difference too. This what Bob found and figured he could
emulate with a few passives added to one of his designs. It is not
necessary to match amps so precisely to make them sound
indistinguishable in normal listening circumstances.

Although the final sentence of this statement is almost certainly true, the
belief that audible differences necessarily correlate with "easy" measurements
is wishful thinking, for which there is no proof or contradiction. The
more-general statement that, if something is audible, it /must/ be measurable
is -- almost by definition -- true.

I agree strongly. The human hearing system is a relatively
inaccurate tool for hearing fine details which show up glaringly
in some very simple tests and measurements.

And your proof or evidence for this is...?

Perhaps the fundamental problem with this dispute (which has been going on 60
years) is that there are no hard data about whether amplifiers really do (or
do not) "sound different". Without such data, it is impossible to even begin
to establish meaningful correlations between what is (or is not perceive), and
measurements.

Both "sides" are wrong, and hold unscientific beliefs based on what they want
to think is true.

PS: If you'd like to hear an amplifier that "measures good" but "sounds
awful", try one of the Crown K series, which were discontinued about a year
after they were first manufactured. They were designed by Gerry Stanley, who
had an outstanding 40-year track record for amplifier design. He apparently
botched this one.

 

" just remove it from the
board, and shake it. Usually, a faulty one will rattle. "

I would fire you. All that shit to determine if something is fucking magnetized at $30 an hour. YOU ARE FIRED if you resort to that shit.

Perhaps youse don't really know what professional standards are around here, but the last half dozen people I have worked for would never hire any of you.

I am not trying to insult you, but if stupid shit like this befuddles you, forget it.

 

[Smarty]

On 6/6/2013 11:54 PM, Phil Allison wrote:

"Smarty"
Phil Allison wrote:
"Smarty"

The outcome of all of this was that no audibly discernible differences
could be reliably reported, at least according to Carver in his claims.

This method obviously did not account for the different dynamic
characteristics of the two amps, such as output transformer saturations
and harmonic spectra / distortion changes over the dynamic range of the
amps.
** Bob Carver only ever made transistor amps - notably under the Phase
Linear and Carver brands. It is generally only tube amps that have such
high
output impedances that speaker loading affects the response audibly.
Carver actually did also make tube amplifiers, and one of such series is
described here in the link below. Other tube designs by Carver were also
developed and sold.

http://www.carveraudio.com/index.php?page=shop.product_details&flypage=flypage.tpl&category_id=1&product_id=2&option=com_virtuemart&Itemid=104&vmcchk=1&Itemid=104

** How many Silver 7s did he sell?

Was it 2 or was it 3 ??

The site covers the Silver 7t & 9t, which are a transistor amps.

The only Carver amps ever sold or advertised in Australia were transistor
models - but I see on the net he has just released some new models that
use tubes.


The comment I previously made was that Carver's prototype could never
***exactly**** match the reference amp he was attempting to imitate due to
differences between the two which would not be amenable to simple transfer
function / frequency response / phase response alone. I mentioned examples
of obvious areas where such differences would still show up.
** Hypothetically only, no way are they likely to be audible.

Bobs emulations were in terms of frequency response and output impedance -
which at least can lead to audible differences.

Bob Carver was and is a colossal bullshitter.

Take his " Magnetic Field " amp nonsense for example - purest marketing
hype and very misleading.



... Phil

Indeed he was a true bullshitter, but he was an extremely capable engineer as well, unlike someone like, let's say, Steve Jobs, a technical light-weight who understood the power of marketing hype and used it most successfully. In a world where actual differences are, as you say Phil, mostly hard to discern, the way that products are selected by unknowing consumers is using the very types of marketing bullshit which these guys throw around.

In Carver's case, he had an amazing and inquisitive mind, and many of
his designs offered things not seen elsewhere. Even the 'magnetic field'
amplifier itself had a remarkable tracking power supply and compact
design which Carver pioneered, and his 'auto correlator' in the earlier
Phase Linear and Carver preamps was a very impressive noise reducer when
tape hiss and other problems were being ignored by many other preamp
builders. His tiny True Subwoofer was another very innovative design. I
was personally a very big fan of his Sonic Hologram, the first consumer
interaural canceller unlike any other device offered at that time except
for a very weak competitor from Sound Concepts using a very noisy bucket
brigrade delay line.

His form of bullshit I find perfectly tolerable since he is person who
knows the engineering details.




> . In the

 

[Smarty]

On 6/7/2013 11:05 AM, Smarty wrote:

Phil Allison wrote:




The comment I previously made was that Carver's prototype could never
***exactly**** match the reference amp he was attempting to imitate
due to
differences between the two which would not be amenable to simple
transfer
function / frequency response / phase response alone. I mentioned
examples
of obvious areas where such differences would still show up.
** Hypothetically only, no way are they likely to be audible.

Bobs emulations were in terms of frequency response and output
impedance -
which at least can lead to audible differences.

Well, some folks would argue that the damping factor, for example, might

be audible if it were to be very different, or that the amount of noise
or type of noise might make an audible distinction, or that the
distortion characteristics could, if extreme, become audible.

Frankly, I don't consider any of these to be "hypothetical", but I agree
that the amplifiers are most likely to sound the same to most people
even if they perceive and claim they hear differences. Double blind
controlled experiments were seldom used to test the human's inevitable
desire to imagine things.

 

[William Sommerwerck]

was a true bullshitter...

I would rather say hyperbolic and self-serving.

In Carver's case, he had an amazing and inquisitive mind...

But one lacking discipline and true curiosity. See following.

I was personally a very big fan of his Sonic Hologram, the first
consumer interaural canceller unlike any other device offered
at that time except for a very weak competitor from Sound Concepts
using a very noisy bucket brigade delay line.

I reviewed the Sonic Hologram for "Stereophile". I was pleased to find that,
with my own coincident-mic recordings, the result was much closer to what I'd
heard standing at the mics. The results with commercial recordings -- which
are rarely simply-miked -- were more variable.

The Sonic Hologram was hardly the first consumer crosstalk-canceller. JVC's
BN-5 did an excellent job. The effect with binaural recordings was nothing
short of spectacular.

The Sonic Hologram attempted to get rid of delay lines by substituting
constant-group-delay phase shift. Such circuits cannot actually delay the
signal. Rather, they shift the waveform envelope. * Given how well the Sonic
Hologram worked, I suggested to Bob that /perhaps/ the circuit did "good"
things neither he nor anyone else was aware of, and he should look into it.
"No, it works the way I say." And that was the end of it.

* I'd better explain this. Imagine you've designed an op-amp circuit to
produce 1ms of constant group delay over the audio band. If this circuit
"truly" delayed the signal, then its output would be zero for the first
millisecond after a signal is applied. But this is impossible, because a
finite input (with zero output) would drive the op amp against the rail. What
is actually output is a signal that -- after passing through the feedback
network -- cancels the input signal. (This is The Basic Principle Of Op-Amp
Analysis.)

You can easily show this with Laplace transforms. I did it 30 years ago, and
am not in the mood to do it again.

 

[Jeff Liebermann]

On Fri, 7 Jun 2013 13:00:10 +1000, "Phil Allison" <phil_a@tpg.com.au>
wrote:

Does my schem show input switching ?

Oops. Nope.

And what about this bit ?

" Make "Y" leads to connect the left and right input signals to both
amplifiers."

Switching amp inputs was un-necessary and would create some audible
transients, but simply using a change-over relay to select between two
amplifiers that are producing virtually identical output signals results in
no audible transients on music or speech.

Guilty as charged. I misread the web page. Sorry(tm).

Another possibility when setting up is to connect the speakers across the
hot outputs of each amp - then adjust input levels to get the least sound.
With identical amplifiers, this should result in silence from both
peakers - which only proves the signal gains are equal as neither amp is
driving any load.

While attending college in the 1960's, I worked for a repair shop that
did warranty repairs for several manufacturers of audio hardware. One
of the chronic problems was missing, or backwards electrolytics in the
audio sections. A gain and freq response check would catch these, but
the owner wanted something that could quickly test the amps and tape
recorders. So, I devised a comparison scheme similar to yours, where
an identical and known working unit was compared with the test amp by
placing a speaker between the outputs of the amps. If anything was
heard out of the speaker, the test amp had a problem. The only
difference was that I applied a 10 ohm load to each amplifier output
so that I could catch a backwards output coupling capacitor. It was
also somewhat useful for checking left-right channel balance on amps
that had ungrounded transformer driven speaker outputs. I later
replaced the speaker with a differential input scope to catch high
frequency differences that couldn't be easily heard. Since this was
essentially a production line affair, such quick tests yielded good
returns.

Unfortunately, my efforts on behalf of the shop were rewarded by being
replaced by a less experienced and lower paid tech. The owner
realized that he didn't need a high priced tech to do such simple
tests, so I was transferred to the camera department and did much the
same work, except on cameras.



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Phil Allison]

"Smarty"

Phil Allison wrote:

Bob Carver was and is a colossal bullshitter.

Take his " Magnetic Field " amp nonsense for example - purest marketing
hype and very misleading.


Indeed he was a true bullshitter, but he was an extremely capable engineer
as well,

** The former destroyed any credibility the latter might have given him.

Some of his amplifier designs were OK while others were piles of utter
rubbish that should never have gone on sale.

That is NOT the hallmark of a "capable engineer".

In Carver's case, he had an amazing and inquisitive mind, and many of his
designs offered things not seen elsewhere. Even the 'magnetic field'
amplifier itself had a remarkable tracking power supply and compact design
which Carver pioneered,

** It did NOT have a tracking PSU - that is one of the many misleading
claims made about it. The "Carver Cube" as it as known was marketed as
something it CLEARLY was NOT and doing that is in breach of consumer
law.

The professional version ( the PM1.5 ) was a near disaster and his other
desperate attempts to eliminate the iron transformer ( eg the PM2.0) were
even worse.

and his 'auto correlator' in the earlier Phase Linear and Carver preamps
was a very impressive noise reducer when tape hiss and other problems were
being ignored by many other preamp builders. His tiny True Subwoofer was
another very innovative design. I was personally a very big fan of his
Sonic Hologram, the first consumer interaural canceller unlike any other
device offered at that time except for a very weak competitor from Sound
Concepts using a very noisy bucket brigrade delay line.

** None of the above are any more than gimmicks - and don't Yanks love
gimmicks.

His form of bullshit I find perfectly tolerable since he is person who
knows the engineering details.

** You are fooling yourself.



.... Phil

 

[Phil Allison]

"Jeff Liebermann"
"Phil Allison"

Does my schem show input switching ?

Oops. Nope.

And what about this bit ?

" Make "Y" leads to connect the left and right input signals to both
amplifiers."

Switching amp inputs was un-necessary and would create some audible
transients, but simply using a change-over relay to select between two
amplifiers that are producing virtually identical output signals results
in
no audible transients on music or speech.

Guilty as charged. I misread the web page. Sorry(tm).

** You are not alone in that - most posters do not read what is actually
written and their replies show the fact by having little or no relevance.

WS is the biggest offender by far.

So, I devised a comparison scheme similar to yours, where
an identical and known working unit was compared with the test amp by
placing a speaker between the outputs of the amps. If anything was
heard out of the speaker, the test amp had a problem.

** You probably have heard of the Quad ESL63 speaker - but did you know Quad
checked each newly completed example in their factory with a similar method
?

One, fully tested ESL63 was compared with each production unit by placing
the two side by side with a flat response condenser mic on axis of both
about 2 metres away. The speakers were set up in an open area with a thickly
carpeted floor and surrounded by acoustic screens. A square wave signal was
supplied to both speakers at some mid band frequency. Next, the polarity of
the new unit was reversed by a DPDT switch while the operator looked at a
scope screen showing the output of the mic.

The test was passed if the signal seen on the scope all but vanished !!

Not just a neat test, but proof that all ESL63s left the factory identical
in amplitude and phase response across the audio band.


..... Phil

 

"One, fully tested ESL63 was compared with each production unit by placing
the two side by side with a flat response condenser mic on axis of both

about 2 metres away. The sp....blabla......"

OK motherfucker, you're right. You don't mind me calling you motherfucker do you ? You ever fuck a broad who had kids already ? That is what I was looking for after someone mentioned that thing about the no feedback between the two speakers.

Yup. Quad was that company.

Anyway, unless you spend alot on speakers, usually you are not going to hear much difference in amps. Even if you do it will be hard. It will have to do with the exact amount of feedback and what of the heavy drive contributing to the dampering factor and all this shit. Whether it reproduces up to 30,000 or 40,000 doesn't mean shit. And whether it is 0.003 or 0.002 percent THD doesn't mean shit. You know there is actually a damping factor curve.

Anyway, I guess I am just going to lay my opinion on y'all now. I think the crossover shopuld have the lowest inductor and a=capacitor possible, or else the damping factor means shit. Same with all bands. there can be many values chosen, but....

Personally, I am into biamping now, and I am doing it on my next system. There will be absolutely NOTHING between my woofers and their amp. It will control the cone excursion very accurately based on the input (music) waveform.

Now, with mt experience and all this shit, I am starting to think something else. NO PASSIVE CROSSOVERS. Each individual speaker is connected to its own individual amp. The crossover is all at line level.

Now that I think of it I shouldn't be saying this shit because this is the next step. Powered speakers, all of them. Not just the woofers, everything. No more blowing the amp, no more all kinds of shit, and clean ? Each fucking speaker has its own fucking amp. Even the tweeteer is DC coupled and even at those impedances it has a high dampind factor.

In other words, no passive crossover at all. This is the best idea in the world and all this shit except for one thing;

It's been done.

 

[William Sommerwerck]

** It did NOT have a tracking PSU - that is one of the many misleading
claims made about it. The "Carver Cube" as it as known was marketed as
something it CLEARLY was NOT and doing that is in breach of consumer
law.

One reviewer -- Feldman, I think -- was given a grossly inaccurate (ie,
totally fictional) explanation of how the Magnetic Field amplifier worked. It
was reported that he was very, very angry about this.

 

[William Sommerwerck]

** You are not alone in that - most posters do not read what is actually
written and their replies show the fact by having little or no relevance.

Relevance is in the eye of the reader.

 

[Wild_Bill]

The Wen model 75 sounds like a pistol-grip soldering iron, which won't have
the necessary magnetic field. The Weller type have a somewhat heavy
transformer inside them which creates the alternating field.

Yes, induction motors are those which don't have brushes.. but I don't know
what the magnetic field would radiate like, although it may work if you had
just a bare motor with a long cord/extension cord so the power could be
applied (and later disconnected) far enough away from the CRT.

--
Cheers,
WB
..............


"micky" <NONONOmisc07@bigfoot.com> wrote in message
news:hv70r8ds0sbl2fqlpibltb7g7968ali6v4@4ax.com...

On Tue, 4 Jun 2013 16:59:36 -0400, "Wild_Bill"
wb_wildbill@XSPAMyahoo.com> wrote:

Magnets aren't good as John pointed out. It's best to keep magnets away
from

I'd done it already by then, but only a little and I'm glad to say it
didn't make the picture worse.

CRTs, including older external speakers which don't have magnetic
shielding.

You could use an electric soldering gun (Weller or similar design) or
possibly a bulk tape eraser.

I don't have a bulk tape eraser or a Weller soldering gun, but I do
have a WEN "75" soldering gun. That's the one in dark red plastic
made to look like an actual gun, a revolver, with indentations between
the places the bullets are supposed to be.

It has one light bulb at the base of the heating element, but the
element doesn't have two separated connections like the Weller does.

Instead it has one thin 2,5" rod, a tube with a heating element and
the return wire in it too.

Do you think that is close enough to the Weller??


After my Freecycle request, someone wrote that a table fan will work
as a degausser. He wrote "The fan I used had an induction motor** like
the ones found on cheap turntables.The magnetism came off the side. It
removed the mess a magnetized screwdriver had caused.(nephew: "Look at
the neat patterns on the screen!")" Is this a risky idea?

**Basically, an induction motor is any motor without brushes, right?
Like almost all small and mediuml fans?

 

[Jeff Liebermann]

On Sat, 8 Jun 2013 14:16:38 +1000, "Phil Allison" <phil_a@tpg.com.au>
wrote:

Guilty as charged. I misread the web page. Sorry(tm).

** You are not alone in that - most posters do not read what is actually
written and their replies show the fact by having little or no relevance.

For the record, what happened was that it was late when I originally
read the web page. The plan was to reply in the morning. However,
when I went back to the web page in the morning, the page wouldn't
load in my browser. (Trust me. This is not a fabrication). So, I
trusted my untrustworthy memory of the page to add my comment, which
was wrong. My apologies (again).

WS is the biggest offender by far.

A little tolerance would be helpful here. In the distant past, I
taught a class which included the usual required reading. It's
amazing the wide variety of interpretations and extrapolations that a
class of students can produce. Many were reading between the lines,
adding futile attempts at reverse engineering that authors intent,
adding parallels to religious or political dogma, or generally letting
the imagination run wild. It's much like that in Usenet, where even
the simplest statements can be easily misinterpreted. In person, we
have clues offered by the tone of voice or personal mannerisms. On
Usenet, we have none of those. I have successfully pissed off people
simply because of my style of writing. If you find someone
misinterpreting what you wrote, I suggest you make an effort to
clarify your writings, rather than criticize the reader.

What fouled me up was the schematic.
<http://sound.westhost.com/absw.htm>
I'm used to seeing relays with coils and relay contacts with diamonds
for contacts. I also don't like connection tags style, where I can't
tell which way the signal is flowing. The schematic does not show a
box for the amplifiers or the "Y" adapter. With a quick glance, I saw
two relays and ASSUMED that one of them switched the input. I did not
read the entire description as I assumed that everything I needed to
know was in the schematic.

So, who's at fault here? Me, for failing to read the web page in
detail, or the web designer, for presenting your concept in a rather
clumsy manner? Certainly, I could have done a more diligent job of
reading, but a better schematic and cleaner web page might have also
been of assistance.

** You probably have heard of the Quad ESL63 speaker

Full disclosure: I'm not into audio these day and know nothing of the
Quad ESL63. I will confess to repairing some audio equipment, but my
level of experience with modern hardware is essentially non-existent.

- but did you know Quad
checked each newly completed example in their factory with a similar method
?

I didn't know that, but such comparison tests are common. We used to
call it "parametric testing" or something similar. CPU, FPGA, and
complex logic systems work the same way. There's no possible way to
test for every combination of input and output. So, they thrash the
inputs on multiple units UUT (units under test) and compare the
results with a known good unit. It's not a 100% test, but it's better
than the alternative of testing everything. I've also done comparison
tests using a vibration signature on mechanical systems. The known
good unit is compared with the UUT for how they shake, rattle, and
roll. If something is loose or mis-adjusted, it will show up as a
different vibration signature.

One, fully tested ESL63 was compared with each production unit by placing
the two side by side with a flat response condenser mic on axis of both
about 2 metres away. The speakers were set up in an open area with a thickly
carpeted floor and surrounded by acoustic screens. A square wave signal was
supplied to both speakers at some mid band frequency. Next, the polarity of
the new unit was reversed by a DPDT switch while the operator looked at a
scope screen showing the output of the mic.

The test was passed if the signal seen on the scope all but vanished !!

Not just a neat test, but proof that all ESL63s left the factory identical
in amplitude and phase response across the audio band.

Ummmm....
<http://www.stereophile.com/content/quad-esl-63-loudspeaker-page-2>
"After this review was written, the second speaker of the first
pair of ESL-63s I received started arcing over on loud passages.
Now, one failure out of two speakers can be bad luck. But two
breakdowns out of two is rather pushing the laws of chance,
and would seem to indicate a real problem."

I don't know what went wrong. It could be the reviewer was
overdriving the speakers or that there was DC on the speakers.
However, if it was a defective speaker, the comparison test should
have shown that something was wrong.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[William Sommerwerck]

WS is the biggest offender by far.

A little tolerance would be helpful here. In the distant past, I
taught a class which included the usual required reading. It's
amazing the wide variety of interpretations and extrapolations that a
class of students can produce. Many were reading between the lines,
adding futile attempts at reverse engineering that authors intent,
adding parallels to religious or political dogma, or generally letting
the imagination run wild. It's much like that in Usenet, where even
the simplest statements can be easily misinterpreted. In person, we
have clues offered by the tone of voice or personal mannerisms. On
Usenet, we have none of those. I have successfully pissed off people
simply because of my style of writing. If you find someone
misinterpreting what you wrote, I suggest you make an effort to
clarify your writings, rather than criticize the reader.

Actually, misreading and unclear writing are both problems. What Phil can't
see are the times I start responding, realize I misread the post, and "tear
up" the response.

Several years ago I took a difficult college-level reading-comprehension test
and aced it. (I'm sure many in this group would do equally well.) Anyone care
to challenge me...?

 

Y'know, no matter what, we are all guilty of hijacking this thread on a trip around the world. I am not talking about trolls or newcomers.

I had been away for a while, things were not like this years ago. I am going with the flow here. It is just hard to fathom the process by which we came from a topic on color CRT purity to Carver's design that had peak currents approaching those of the output of a sustain board in a plasma TV (might be an exageration, not sure) and his fetish for bucket brigade devices.

Then we have a thread about the hifi section of an old Beta and we get to surround sound and all the aspects of it's development, cradle to grave and SQ, QS and their relative relevance and of course sonic holography which is back to those bucket brigade devices.

Did you know that some scientists have found that CO2 reflects IR and therefore it causes global cooling rather than warming ? That part is true, however apparently some bozo faked a Time cover with it or something. Like I care what Time magazine says. Point is, China doesn't give a fuck about global warming, they give a fuck about money, as should we.

Also, next time Israel fucks with a shipment of arms to Syria, they are likely to get their asses shot the fuck down. Then they will whine to the world that someone attacked them and the fact that they were in the other country's airspace attacking shipments lawfully destined for the lawful government of that country will not matter. But yes, I think they are going to find out that others also have MIGs.

A federal court has ruled that you do not have the fundamentla right to produce and consume the foods of your choice. they ruled this way because the party involved did not PROVE this to be a fundamental right. Dontcha think they should err the other way ? Not in AmeriKa.

Now THAT'S how to hijack, amateurs.....

LOL