John Curl's Blowtorch preamplifier part II

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You guys can believe anything that you want. IF you think that a null test will answer your questions about audio, then believe away. I found different, 35 years ago. Null tests remind me of an old test for 'witchcraft' that threw the suspected person in water, while bound. If they floated, it PROVED they were a witch, if they sank, then they would drown, but God would sort them out.
When these early 'blind' tests were first evolved, a great many mistakes and biases were added in, to get the result desired: A null result. In fact, an extraordinary result is usually thrown out, because it does not fit in the presumption that the test was not possible to pass. I am sure that neither I nor almost anyone else would pass SY's blind test. Perhaps Michael Fremer could, but SY would probably throw his result out, as being 'untypical'. There is no winner here, nor any real resolution of what we can hear with ABX and similar tests, when it comes to serious appreciation of audio quality.

My test offer did not specify ABX. I would be happy to run A-B preference, since you have said in the past that this is what you prefer. The only rule- no peeking.

Ready to find out what your ears actually tell you when you actually trust them? Offer is open: your system, your choice of music, you can control volume and specify when things are switched, go back and forth as much as you like, take your time.
 
I thought that was professor schrodinger.:confused:

jn

Your all right, sort of
While not Mr TV or the Cat in the hat / box man, This Professor Farnsworth said it , more of his wisdom;

Farnsworth; "But, as Deepak Chopra taught us, quantum physics means anything can happen at any time for no reason. Also, eat plenty of oatmeal and animals never had a war. Who's the real animals?"


Futurama- The Best Of Professor Farnsworth - Video
 
My test offer did not specify ABX. I would be happy to run A-B preference, since you have said in the past that this is what you prefer. The only rule- no peeking.

Ready to find out what your ears actually tell you when you actually trust them? Offer is open: your system, your choice of music, you can control volume and specify when things are switched, go back and forth as much as you like, take your time.

I think we have all been here before.
 
My test offer did not specify ABX. I would be happy to run A-B preference, since you have said in the past that this is what you prefer. The only rule- no peeking.

Ready to find out what your ears actually tell you when you actually trust them? Offer is open: your system, your choice of music, you can control volume and specify when things are switched, go back and forth as much as you like, take your time.

Being all serious and such for a moment, when it really matters to know for sure, you HAVE TO do it without “peeking” as you put it, without prior knowledge as I would put it.

If you think about it, how does our brain and hearing system compose a 3d image in our head?

It takes just two ports, two inputs and makes a 3d image where in the world we live in, one needs one more frame of reference than what one wants to specify. For example, 2 microphones describe one plane, 3 describe two and 4 can describe 3 dimensions.
We hear 3d because we have a learned system, the response measurements taken next to ones ear drums show a myriad of response aberrations many of which change depending on the incoming angle and height of the sound.
To an engineer these horrid looking flaws are “problems” but in reality we have learned all of these things subconsciously and instead of a cascade of changing comb filters, response changes and reflections as a measurement shows, we “hear” and can direct our eyes towards the source of sound moving through space.

One of the fellows I work with did some early work on how we hear directions and such and made a set of recordings called LEDR which create a moving stereo image using the most common traits of ears, these might be fun here;

Online LEDR Sound Test | Listening Environment Diagnostic Recording Test

In the old days, Don Davis made “in the ear” recordings which actually put tiny tubes connected to microphones into a person’s ears and recorded from there. I heard one of these at Don’s farm, a recording made at the Indy race track and it made the hair stand on the back of my neck.
The problem was only one person could listen at a time and the speakers had to be on the floor on either side of the chair to minimize interaural crosstalk.

In fact, we also depend on our eyes to “hear”, for example with voices, what we see can actually over ride what we hear;

https://www.youtube.com/watch?v=G-lN8vWm3m0

The problem is, our brain is always filing in a lot of the details for us, without our knowledge and we are not aware of our senses all being somewhat tied.

Now, if you haven’t seen it, here is a great example, a demonstration of one’s brain filling in the spaces in the absence of information.
The first part is JJ, a well known audio guy, listen to what he says but when Poppy is on, play close attention and wear headphones. This demonstration only works once! Once you have seen it, you can’t turn it off in your head.

https://www.youtube.com/watch?v=BYTlN6wjcvQ

They test hearing with headphones to block distractions and provide a known spl, but in addition without any clue when the sound is on or off is to remove all prior knowledge, there is no red light, no operator nodding their head, it’s entirely on your ears ability to hear the sound, or not.

If you can’t tell the difference between two cables, capacitors etc when you switch back and forth at your leisure, with the program material of your choosing, one might be tempted to focus on changes which are audible in this way as these add up.
 
Tom, I got a similar feeling the first time I heard a correctly set up Ambisonics demo. Really spooky! And likewise impractical. I maintain that our principal limitations now are in the realm of encoding and recording. Conventional 2 channel stereo has probably gone just about as far as it can in terms of really advancing the art of sound reproduction.
 
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If you think about it, how does o in reality we have learned all of these things ur brain and hearing system compose a 3d image in our head?


We hear 3d because we have a learned system,

but subconsciously and instead of a cascade of changing comb filters, response changes and reflections as a measurement shows, we “hear” and can direct our eyes towards the source of sound moving through space.

https://www.youtube.com/watch?v=G-lN8vWm3m0

The problem is, our brain is always filing in a lot of the details for us, without our knowledge and we are not aware of our senses all being somewhat tied.

yes. It is all learned.... listening and identifying and understanding what we hear. Probably why some listen for things which others dont and hear things others don't.


THx-RNMarsh
 
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yes. It is all learned.... listening and identifying and understanding what we hear. Probably why some listen for things which others dont and hear things others don't.


THx-RNMarsh

Are you sure? having a plurality of children I have been involved in a number of hearing tests and small babies have little issue picking up sound direction. It would seem quite a lot of the HRTF is there at birth, even if it enhanced by learning. I would be interested in any references to correct my purely observational experiences.
 
The first part is JJ, a well known audio guy, listen to what he says but when Poppy is on, play close attention and wear headphones. This demonstration only works once! Once you have seen it, you can’t turn it off in your head.

Which demonstration? Stairway to Heaven or Legi_lature?

One of my favorites is this demonstration of the McGurk Effect.

http://youtu.be/G-lN8vWm3m0

se
 
The distortions and surface noises not withstanding, the level and dynamics just blew me out of the room.
My self thoughts were how the hell can this be reproduced ???.
There were no lows to speak of, and no highs to speak of either, but the vocals sense of real power was quite astounding.
The digitally processed/cleaned up recordings of EC referred to above are quite astoundingly good also.
Caruso and Melba are top notch, on CD - I've had both running at live volumes, tremendous intensity, with a very strong sense of space - picking up clearly the ambience around the piano, playing well behind the singer... very good examples of how the microphones have picked up the detail on the most primitive of recordings, which the ear can decode successfully if the playback system works well enough.

Speaking of pianos, solo classical recordings are a good subjective metric for SQ. Many systems are quite miserable at this, fall badly at the first hurdle as soon as a bit of volume approaching realistic is called for - as good progress is made the elements of the acoustic qualities of the real thing, that we are all familiar with, start to fall into place - at a certain point the recordings can start to sound "better" than the real thing, because of the combination of the quality of the piano, pianist, recording environment, and miking techniques in the recording ...
 
Yes,
that learning thing can be a real pain in some respects. Once you learn something or become aware of something you just can't turn that off. When you train your ear to listen for certain things or become aware of a specific type of distortion you just can't turn that off and for me at least that can really take away from the joy of just listening to the music. With background music I can somewhat ignore certain things but when I want to listen I hear or miss something that I am expecting, So our learned hearing and our biases start to control our listening experience. you just can't undo what your brain is expecting. As the demonstration that SE just posted of the McGurk Effect out vision really does change everything, I think this is why some so resist doing blind testing, it just doesn't reinforce what it is they are expecting or have a bias towards.
 
yes. It is all learned.... listening and identifying and understanding what we hear. Probably why some listen for things which others dont and hear things others don't.


THx-RNMarsh
Indeed that's the way it goes. The way out of the nightmare of determining what is good sound or not, is to learn to recognise precise flaws - as soon as one's way of listening devolves back to deciding whether "A sounds better than B" then the ability to differentiate will be dramatically worsened - the mind will extract the best qualities of A and B, and then start filling the gaps on repeat listening - it's a doomed exercise ...

Hence the use of "poor" recordings to troubleshoot - these will intensely emphasise the weaknesses of the playback chain, making it easy to pinpoint where the problems lie.
 
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