It all starts here, but there are at last 25 other relevant documents that can be found using google.
AES E-Library High-Resolution Subjective Testing Using a Double-Blind Comparator
Telefunken is still german-owned (Telefunken -HOME) except a brand name licensee in the USA who produces professional equipment (TELEFUNKEN-ELEKTROAKUSTIK.COM | TELEFUNKEN Elektroakustik™ -) with the Germans blessing.
Telefunken appears to have a better reputation abroad than in Germany.
Having grown up in Germany myself I will always think of them as the producer of cheap tat and that clock radio is exactly what I would expect from them.
Having had a quick glance at their history it becomes clear that Telefunken used to develop and produce high-quality professional kit and cheap'n'nasty consumer fodder. Unfortunately that consumer fodder is all that I remember them for having grown up in the '70s.
To the best of my memory Loewe were always one of the more upmarket televisions.
Nordmende I remember mostly from catalogue retailers.
In home hifi terms Nordmende, Telefunken and ITT SchaubLorenz were the bottom, Grundig and Braun the middle and Revox at the top.
On the turntable front Dual covered bottom to middle and Thorens middle to top with their various models.
Nordmende I remember mostly from catalogue retailers.
In home hifi terms Nordmende, Telefunken and ITT SchaubLorenz were the bottom, Grundig and Braun the middle and Revox at the top.
On the turntable front Dual covered bottom to middle and Thorens middle to top with their various models.
Number 1 for part/build quality. For an example, do a search for (crt) tv boards.
Till the entry of plasma tv's, the ones by other brands didn't even come close.
Loewe used all FR4 boards, at a time when all others were not.
Build quality of lcd tv's by Loewe was also the very best, but no longer sufficient demand at the accompanying price level, reason for the bankruptcy in 2014.
Long long time ago, Nordmende manufactured rather good radios, also smart looking.
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It is hard to imagine the kind of warranty they gave back in the old days.
An externally hosted image should be here but it was not working when we last tested it.
I don't have access to the AES article.
Arney, I am asking more detail of the testing setups that are quoted in your's and other tests.
QSC used to manufacture this ABX test box -
QSC ABX_manual.pdf
Those specs are very not flash....I was being polite, they are hopeless.
Dan.
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Of course you do. Anybody can access AES articles over the web. It just takes a few bucks - some tiny fraction of the cost of a high end audiophile cable, for example.
Of course I understand that audiophiles can spend $thousands on snake oil audio components without batting an eyelash, but $20 for real science is often mission impossible.
Here's a link to some of the technical details of the original ABX Comparator:
ABX Double Blind Comparator Hardware
Here's a link to a currently commercially available ABX comparator:
avahifi - The AVA ABX Comparator Switchbox
Here is a description of the wiring of an ABX test of some digital audio hardware:
http://www.bostonaudiosociety.org/bas_speaker/abx_testing2.htm
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We had nothing to do with the design or construction of any ABX gear but our own. The QSC box is rated very conservatively. I have one on hand - it works far better than you might want to think.
Here are the schematics of the components of our ABX Box:
Relay driver circuits:
Relay contact wiring
Hand held controller wiring
Logic and control unit schematic
Line level is my concern.
Why 33R earthing resistors, and where is the level matching ?.
Dan.
Our goal for our switching equipment was audibly silent and transient-free switching, even when comparing phono and mic preamps. If you can do that, line level is a slam dunk.
You don't know?
Common practice for balanced circuits. Reduces the probability of hum and noise in some situations.
Hopefully in the UUT's.
If not, added on by appropriate means which can vary all over the map depending on what kind of UUT's are involved.
Yeah ok, correct switching to eliminate switching transient noise.
Layouts and loop areas are quite critical.
Ok, I missed balanced connection.
Still, all connections including earths must be switched to eliminate earth current cross pollution of audio signals, more especially when running unbalanced.
Yeah, ok, so what really is "appropriate means which can vary over the map" ?.
Adding attenuators of undefined characteristic and causing common earths is changing the equation by adding extra variables that deviate the DUT's from their original usage conditions.
Dan.
Not true. Like I said, we achieved audibly transient free switching of both phono cartridges and microphones.
Why should one accept such hyper-generalties from someone who doesn't recognize wihtout being told several times what are clearly schematics for balanced circuits?
It means understanding that the appropriate means for audio attenuation varies with the circumstance. That's not a run-around, it is simple truth.
I'm not here to teach a class in grounding or signal switching - there is a ton that is now published about it if you know where to look. Unfortunately it was mostly published after 1983, which means that back in the day many people had to work it out for themselves.
That's what I've been trying to convey!
Of course our attenuators and other matching devices de jour were not undefined, and had passed relevant performance tests of both a technical and subjective nature.
Being credentialed (mostly degreed) and experienced audio engineers we knew that we would have to address that issue. We used generally accepted technical practice, plus whatever we had to invent, to monitor performance and implement solutions that avoided that problem.
For example, the schematics I just published implement a novel (never ever seen it described any place else) highly reliable means for transient-free audio switching that is also described in the AES paper. Only took me about a year and a few generations of prototypes to figure it out. ;-) If you know what it is, it is common sense - stupid dumb.
Your guess is probably better than mine!
More info about it here:
Audio by Van Alstine ABX Comparator Review, Part 1: Audio Store & Wiring - Dagogo | A Unique Audiophile Experience
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