John Curl's Blowtorch preamplifier part II

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You are missing the point. If you cannot hear a difference 'blind', but prefer a certain sighted result and accept that it is YOUR bias that causes that preference, no one here is going to argue with you. It's when you deny bias and still claim your preference is easily audible that eyebrows are raised.

True, of course.
And there are those that say they can easily hear a difference when peeking and complain that with a controlled test that difference 'somehow disappears'. A total ignorance on perception and psycho-acoustics most probably. Or denial.

Jan
 
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In my simplistic mind I handle it as the difference between sound quality and total experience. I would estimate that, for those of us who still play vinyl for most its the ritual that makes the experience (I worry SY is part vulcan so is an outlier).

No different from some the silly kit car I use to own. I didn't get to my destination significantly quicker, but damn I felt good when I got there. Or for that matter the fact that port tastes better from a nice cut glass decanter.
 
In my simplistic mind I handle it as the difference between sound quality and total experience.

Mine as well. That's one big reason I use tube equipment.

Linear Audio said:
If, like the magic show, the goal of a hifi audio system is to provide entertainment by creating an illusion, there’s more than just the pure soundfield to be considered. But the informed designer needs to know what counts for the actual auditory parts of that sonic illusion and separate that from the rest....

...what we are interested in finding out is if a design choice is audible. Whether it looks cool, comports with audio fashion, satisfies philosophical urges, gives you pride of ownership, or it just makes you happy to have when playing your music are separate design issues. But fundamentally, to evaluate audibility, we have to trust our ears, and not help them out by using other senses or our conscious or unconscious preconceptions.
 
Did the 997Hz question get answered? From the DAC A/D testing side you want all codes to be exercised within a reasonable time ideally the frequency is a prime factor of all sampling rates. I never thought about it but exactly 1kHz @ 96kHz sampling only needs 48 codes (only 24 with sign). Fitting into exact FFT bins is more an ease in signal processing issue.
 
Thanks for the informative links. :)
Checked some Caruso recordings on you tube, they are unbelievable. Considering they are 100 years old. There was a mention of audio and vision (blurred photos) in Thomas Stokham article; Check this example 'Deblur'.
I don't think it would be impossible in near future with old recordings one can separate each instruments digitally, fine tune them with stock audio samples of that particular instrument and remix whole recording.
Regards.
 
<snip>
Yet, noting that nothing is this world is ideal, but that we try to get as close as possible to that unreachable ideal, I suggest that shutting off the peeking mode makes a giant stride forward towards some sort of trustworthy test.
If you don't, you've lost before you even start.

Jan

Although it might be a "giant step" it does not help if the results (or more precise the conclusion drawn from the results) are not correct ;)

As long as you do not know if your test is good (enough) you can not draw sound conclusions from the results.

You are missing the point. If you cannot hear a difference 'blind', but prefer a certain sighted result and accept that it is YOUR bias that causes that preference, no one here is going to argue with you. It's when you deny bias and still claim your preference is easily audible that eyebrows are raised.

Which way do you decide if someone could hear a difference "blind" ?
To run any kind of "blind" test is not sufficient as long as you do not know if your test is most probably good enough.

A listener should accept that a bias might be the cause for his preference, but the other should accept that a real difference might be the cause for his preference.

True, of course.
And there are those that say they can easily hear a difference when peeking and complain that with a controlled test that difference 'somehow disappears'. A total ignorance on perception and psycho-acoustics most probably. Or denial.

Jan

To deny the possibility that the test situation itself was the cause for not being able to reject the nill hypothesis would be a total ignorance on perception and psychoacoustice testing as well.... :)
 
A best mate of mine from school days (also named Enrico) once played to me on a wind up player with horn output an an original 78 EC recording...Ave Maria.
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.

One moment in Aus political history is known as 'The Dismissal'.
In Nov 1975 the then Governor General (the British Queens representative) sacked the then Aus Prime Minister, Gough Whitlam.
The outgoing Prime Minister held a press conference on the front steps of Parliament House declaring his rage.
In the press scrum/rush, the only film captured was seriously faulty.
The image was ok, but the audio captured included drastically bad flutter, probably due to the audio loop being not threaded correctly.
The Dismissal 1:55.
Notably in more recent telecasts of this event the audio has been cleaned up perfectly, presumably by modern DSP means.

Dan.
 
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Thank you. Two comments

1. These two are not based on the same original event. They are from different recordings.
If you would like to compare 78 vs reworked from the same source, see here
Enrico Caruso Arias and Songs
Choose a line, click on the “Details” tab on the right and choose a digital remastering with the same date as the 78rpm, e.g. on this one Enrico Caruso sings E lucevan le stelle
Choose the date 01-02-1904

2. The RCA release didn’t have the added orchestra. The software tool that Thomas G. Stockhamsoft designed, did have the capability to separate the voice of Caruso from the music instruments but this option was not chosen for the RCA release.
His interview by Daniel Levitin is very interesting and informative
Note: In that interview, the mentioned Al Oppenheim is the one of the professors that teach on the course which SY suggested to JC.


Did the 997Hz question get answered?

Scott I first read of using the 997Hz signal in one of Audio Precision papers.
For the reasons that you mention, it was called “the proper 1kHz test signal for the digital era” or something if I recall correctly (I made a search in my files but I can’t find it, sorry)

George

>Edit: I found it (page 5, left column)
Fundamentals of Modern Audio Measurement (C.Cabot)
http://www.ap.com/download/whitepapers

http://www.hit.bme.hu/~papay/edu/Acrobat/Fund.pdf
 
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Short version: "I like to peek."
Aw Jeez.jpg

Dan.
 
I had an engineer who worked with me who took it one further and monitored the ac power lines of a power amp while playing music. Music is there also !!

Just thought I'd throw that in the mix to think about. Messy business, this audio.


THx-RNMarsh

Why would anybody expect the music to NOT be on the line???

It's there in the form of modulated haversines aand gated bleedthrough during diode on conduction, to chassis ground loop currents, with supply mutual coupling on either side of the cap bank, with the PC safety grounding conductor and IC shield currents...

I explained that a decade ago on this site.

Welcome to the party pal..:D

jn
 
waste of money and time

1 Page 19, Christian stores a copy.
2 He charges a fee to his clients
3 Data bank + Switzerland = Swiss banking :clown:

I standard use a sample rate converter for CD's (one-off D2D-1), but would gladly pay for interesting recordings in 24/96.
Only issue for distributing would be payments of digital royalty rates for downloaded material.

(there's an 'it'sy 'bit'sy island in the Caribbean which is far more interesting than Swiss safe deposits since pre-2k days)
 
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