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Old 11th August 2012, 03:29 AM   #26001
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Quote:
Originally Posted by Pano View Post
What do you define as "artificial" records? Is it the recording technique or the sources themselves?
Welcome to the discussion Pano!

It is what I meant on the previous page:

Quote:
Originally Posted by Wavebourn View Post
I mentioned phase coherence issue on arrays with a real sub. Something tells me that the body participates as well, not only ears.

However, it may be no issue if to play the majority of modern records. They not only have multi-dimensional mix, but often multi-environmental, when different instruments were recorded in different rooms, or even different reverberations applied. When the record is artificial it will always sound artificially, no matter which speakers to use.
The discussion was about phase coherence: where it is required, or not. Some pelple believe that it is enough if the reproduction contain only needed set of harmonics, waveshape does not matter, because ears do not recognize it. I know it is wrong, wave shape matters. If we want to fool imagination as if the sounds are real we have to preserve wave shape. However, if we synthesize something artificial it may be not necessary.
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Last edited by Wavebourn; 11th August 2012 at 03:37 AM.
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Old 11th August 2012, 03:31 AM   #26002
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Quote:
Originally Posted by Pano View Post
Glad you said that and not me. Whenever I say that really great systems reveal great stuff in what many consider "bad" recordings I get slammed for it.
You know, "Rubbish! Better systems just make bad recordings sound worse." Or words to that effect.

While I wouldn't go so far as to say that all recordings can be revealed to contain hidden sonic gems, many do. Part of my fascination with really great systems is their ability to let you hear past the recording flaws and into the music. Not a lot of folks agree with that, it seems.
+2. I have noticed the same thing many times over the years. After improving components, I go back to some recordings I thought were not that good, and wow. Sometimes it is the equipment that gives a particular recording a bad rap.

Good observation.

Last edited by Positron; 11th August 2012 at 03:36 AM.
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Old 11th August 2012, 03:58 AM   #26003
Pano is offline Pano  United States
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Quote:
Originally Posted by Wavebourn View Post
The discussion was about phase coherence: where it is required, or not.
Right, I read that in your post, but was confused by the term "artificial." I do tend to prefer minimal mic and mixing techniques as they often sound more real to me, but my point was that in the hands of a skilled engineer, it can be quite surprising how realistic totally fake set-ups can sound. Like good C.G. in movies, you don't know it's fake. Or even if you do, it can seem amazingly real.

Now that said, my wife just bought me an old London Records Phase 4 Stereo LP from 1962 that was recorded on a 20 channel mixer and 4 track master tape. It's spectacular, but not very real. Doesn't matter tho, it's crazy fun.
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Old 11th August 2012, 05:05 AM   #26004
RNMarsh is offline RNMarsh  United States
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Originally Posted by SY View Post
Earl has published a great deal of data on applications of the metric. What new thing are you looking for?
There is plenty of data floating around similar to Earl's for a long time. His is more up to date. I want a range of new test instruments or hard/firmware which does more than harmonic and thd and Im et al. With features which would integrate Earl and other info into test and measurment equipment in a convenient to use and plots which have the added weighting and other such parameters besides just/only electrical phenominon. [Like weighting which is standard feature in SPL measurements.]

In other words... measurements which correlate a little better to hearing etal. Even if they are an optional feature to the basic instrument.

Thats all I want. -- Signed - test equipment Junky. RNM
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Old 11th August 2012, 05:09 AM   #26005
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Richard, we should 'fire up' the old Hirata box and measure something different. You should read up first on Hirata. If you want something DIFFERENT, yet meaningful.
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Old 11th August 2012, 05:21 AM   #26006
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Originally Posted by Pano View Post
Part of my fascination with really great systems is their ability to let you hear past the recording flaws and into the music. Not a lot of folks agree with that, it seems.
Precisely.

Quote:
Yes - on this I concur with you Pano and disagree with Frank. His claim that 'all recordings do' is actually only 'all recordings Frank has heard'.
I've made a point of hunting out extremes in recording quality, and the poorest possible transfers, just to test out how far you can take this. And I'm pleased to say that I have yet to be proven wrong, even when I, in a weak moment say, No way ... I can't rescue that recording!!, and then further down the track realise that I had been listening to reproduction that wasn't as good as it could be.

And this depends on where the natural strengths of a system are. My current setup takes a bit of fine jigging to handle really dense recordings, my latest "hurdle" is a 2007 album by the Foo Fighters, from the library -- you don't think I would buy this sort of stuff!!

Frank
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Old 11th August 2012, 05:30 AM   #26007
jcx is offline jcx  United States
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Originally Posted by RNMarsh View Post
It appears that the compressed sound from MP3 is on the order of yielding up a dynamic range of only 2 to 1. Anyone know fer sure?
no reason for a limit I know of - dynamic range compression should be orthogonal to psychoacoustic lossy data compression

I once tried a direct encode/decode experiment which showed single sine had ~ -80d spurs&distortion Schematics needed for 3V 1KHz Sine wave generator

MP3 may often be used to distribute pop music - which is mastered with heavy "Loudness War" dynamic range compression - but that is just correlation - not causation


I have certainly used similar Ogg Vorbis and WMA data compression formats on decent jazz CDs without obvious loss of music dynamic range

Last edited by jcx; 11th August 2012 at 05:46 AM.
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Old 11th August 2012, 06:38 AM   #26008
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Quote:
Originally Posted by RNMarsh View Post
There is plenty of data floating around similar to Earl's for a long time. His is more up to date. I want a range of new test instruments or hard/firmware which does more than harmonic and thd and Im et al. With features which would integrate Earl and other info into test and measurment equipment in a convenient to use and plots which have the added weighting and other such parameters besides just/only electrical phenominon. [Like weighting which is standard feature in SPL measurements.]

In other words... measurements which correlate a little better to hearing etal. Even if they are an optional feature to the basic instrument.

Thats all I want. -- Signed - test equipment Junky. RNM
Ian Hegglun has an interesting article in Linear Audio Vol 4 about weighing regular THD measurements giving results that appear to correlate quite well with listening tests.
For instance, it has always been difficult to express the measurend xover distortion in numbers correlating with listening tests because their effect depends so much on dynamic issues, signal levels etc.
With Ian's weighing principle the correlations seems much better.

jan
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Old 11th August 2012, 06:53 AM   #26009
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If weighted measurements will become standard people will say one day, "Wah! Wavebourn amps always measured great, but we did not know that!"
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Old 11th August 2012, 09:31 AM   #26010
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Originally Posted by gpapag
I would like to ask if there is a way to derive the Gedlee Metric of the DUT from the FFT (amplitude and phase of the harmonics) of the output (OK at some different signal levels too)?
I would think that in theory it ought to be possible since the waveform gives you the in-out function (assuming sine wave input) and the FFT preserves all the information in the waveform.
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