Double blind tests

Aristotle in fact believed in a round earth.

 

I was gonna say that didn't sound right. I thought it was pretty much understood amongst the ancient Greeks that the earth was spherical.

 

It was only in the early Christian period that the 'flat earth' theory gained ground amongst theologians such as St Augustine; interestingly their 'reasons' for such a theory were theological rather than scientific.

 

I thought the expression round earth meant spherical earth...

 

Well, yes. Round earth = spherical earth = what Aristotle and most of the Ancient Greeks believed in. Flat earth = flat earth = what Saint Augustine and other early Christian theologicans believed in. I think there has been some wire-crossing going on here; I took you to mean that Aristotle had rejected the idea of a round earth back in 350BC.

 

It does, but not literally. Strictly "round" is a two dimensional description, whereas spherical is 3 dimensional. Its exactly the same difference between something being square and something being a cube. When people say the earth is round they really mean that its spherical ... after all if the earth were really flat it could very well be round too. Round and flat like a pancake rather than round and spherical like a ball.

 

Of course not...

 

O, Lord, what have I started now...

From where I sit, at the time of writing, the earth appears to be relatively flat - as it has done for most of my life. This is a subjective observation.

However, since I am open to information and opinions from other sources, I actually think that there is good reason to believe that the earth is roughly spherical. This is an objective assessment based on the best available evidence now. But nothing is set in stone for all time - how can it be? "It is impossible to step into the same river twice" (Heraclitus).

Returning to the subject - of double blind tests - I do think that some people are missing the point. A double blind test measures what it sets out to measure. The results are true for that equipment, in that place, at that time, and for those people. Nothing more and nothing less.

No-one can accurately draw inferences regarding parameters which were not measured in that trial. Listening tests by individuals or groups cannot prove that, for example, cables do - or do not - add, distort or detract from the sound of other equipment in other circumstances.

However, I do think that the fact that the participants in double blind tests cannot be influenced by knowing the brand/model means that a double blind test must be more impartial than one in which they know what is being tested

Until there are more sensitive objective methods of measurement which cover the whole of an audio system from source to output, not just one component at a time, the choice of audio equipment can only be subjective. You pay your money and make your choice.

 

Well you could use a better sound output on the PC. And you could test your ability to hear small level differences, various frequency response aberrations, distortion levels, noise, all sorts of things. Just to find out what they sound like and what is 'obvious' and what is not.

If there were an 'imaging' difference between two interconnects then this would be obvious too, given appropriate samples. And if the difference vanishes when passed through 24bit/96kHz or better processing then I think all CD users can breath a sigh of relief...

Paul

 

I am now totally confused. So is the earth flat or a sphere?

I know .... lets start a poll.

http://zerogain.com/forum/showthread.php?t=16654

 

Hi,

Neither. Of course.

It is almost, but not quite an oblate spheroid.

But only from a certain viewpoint.

From a different viewpoint it is flat. So, now we are back to general relativity, where what is observed depends on the position of the observer.

Ciao T

 

Actually, it's special relativity - general relativity is concerned with gravitation -and it's to do with what is observed (in terms of mechanics) may differ between two frames of reference if the two frames of reference are moving relative to each other.

:MILD:

 

Paul,

I have a feeling that the 24/96 AD on my cheap PC card (or even an expensive one) is still poor. Now a professional A/D or D/A may be different. So in order to avoid having to do a DBT by taking plugs in and out of sockets we digitise the signal and use software to switch. As always the theory is excellent but in practice it gets cheapended. If you hear a master digital recording at 24/96 ( or better) and then compare that to what a PC board does to a signal you may be less confident about what these things do.

However, it was fun to play with this toy. But the subtle effects got a big fat zero difference, which could be me or possibly the test equipment used. My PC speakers are crap at responding to 20Hz sounds so digitisation loses 20 Hz sounds or is it my methods

And no I am not questioning Nyquist theory I am questioning the engineering used. However at £5 a shot what else do you expect?

 

Hi,

I have the what you might call "pro-sumer" Presonus Inspire which is basically a "Pro" external firewire interface, 96/24. The actual performance is barely 16-Bit equivalent in actual measured terms, so this £ 150 thing is good enough for production quality control measurements, but not for high quality recordings, playback or even for development.

I think to get a decent soundcard the cheapest is the Emu 1616M which has an external audio dock and local host card (PCI, PC Card available). This at least offers genuine 20-bit equivalent performance. Not exacly cheap at over 300 Quid. Still, might affordable next to a high end CDP....

Ciao T

 

Er could be general.

General deals with the more general (?) case of motion between frames of reference (in particular acceleration) and special with the special(?) case of constant velocity between frames of reference. General also deals with the similarity between accelerating frames of reference and gravity i.e. without external stimuli you can't differentiate between the force felt from acceleration and the gravitation force. So as far as the universe is concerned the effect of the earth on our region of space-time is relatively (sic) small and our space-time is er......flat. So it is all flat.

Also our Greek friends not only only knew the Earth was round they had measured its diameter.

 

Yep. It's amazing what can be measured

-- Ian

 

I wouldn't do it with anything that could be considered 'PC speakers'...

I have experimented with an M-Audio Audiophile 2496 (currently very good value) into Stax headphones. Sounds reasonable. The issue in my play area is background noise.

Paul