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Old 29th December 2012, 02:00 AM   #31881
fas42 is online now fas42  Australia
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Next step, comparing the DXD, 352, with 96, no 192 on offer: same story as with the other 2L sample recording ... the frequency content at well below ultrasonic is markedly different, peaks in the difference waveform spectrum are between 50 and 500Hz! Visually, amplitudes at up to only -30dB down.

As a flavour of the level of disparity, see below. Horizontal in seconds of course, vertical scale is expanded, goes to 1. So, 0.01 is -40dB down ...

Frank
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Last edited by fas42; 29th December 2012 at 02:11 AM.
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Old 29th December 2012, 02:38 AM   #31882
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Dimitri, so what? Did you think of it too? Did you read Mead Killion's paper 40 years ago?
Not everything is obvious until it is pointed out. It is always obvious after the fact.
If you want to be helpful, find the equation for distortion from a mike capsule with a varying capacitance under vibration against a fixed load capacitance. I tried for about an hour, but to no avail. It is out there somewhere.
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Old 29th December 2012, 02:42 AM   #31883
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Okay, shut off the fire alarms: looks like I led myself astray, this might be all about fine tuning the scaling factor between different resolution versions, give me a chance to play with this a bit more -- 2L may be shiny clean as regards equalising ...

Frank
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Old 29th December 2012, 02:46 AM   #31884
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Once again: This is WHERE I got my first insight. Mead got it from earlier work, so what?
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Last edited by john curl; 29th December 2012 at 03:15 AM.
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Old 29th December 2012, 03:39 AM   #31885
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Quote:
Originally Posted by gpapag View Post
I'm so happy to read that, after all those years, fighting against the vinyl nostalgics.
At the very beginning of the digital recording, while so much sound engineers were talking of the DACs quality, i pretended that most of the audible differences were due to the analog stages after the DACs, not the DACs themselves.
Used a cheap Philips cd player with a Delta sigma 14 bits DAC followed by a modified analog stage to demonstrate-it in my studio.
For me, the difference between vinyl and digital (whatever the sampling rate/bits) is the same than Technicolor/high resolution digital movies.
Now, i can understand why some, like "our thread's Lord" can prefer the "The train arriving at La Ciotat station" From Louis Lumière to the last blog buster movie .
With the risk to be remembered as the "Master of the steam engines".
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Old 29th December 2012, 04:10 AM   #31886
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Would likke to add that, if, that the beginning of CDs, so many records were truly sounding "aggressive"; it was only due to aggressive tone correction done during mixing, to pre-compensate the vinyl losses.
Magic rooms were using studio monitors equalized to simulate as much as possible those losses, so what was in the tapes were good for vinyls (or on those monitors) and bad for strait digital.
The curtain between the original and the auditor introduced by the vinyl was nice too to mask some distortions and defects and good for increasing the place for our imaginations.

I remember how i was shocked by the poor sound quality when i first listened to the digital copy of the Beatles's "revolver" album, while it was so fantastic on the 1966 AM radio's programs !
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Old 29th December 2012, 05:15 AM   #31887
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Okay, shut off the fire alarms: looks like I led myself astray, this might be all about fine tuning the scaling factor between different resolution versions, give me a chance to play with this a bit more -- 2L may be shiny clean as regards equalising ...

Frank
Better nulling by applying an attenuation of -0.23dB to the 352 version, that's such a nice, obvious figure! So get a more reasonable looking balance at that precise point of the waveform. The trouble is, just down the road again there is some excess energy happening at other frequencies, as in the 2nd image.

Also, looking at the spectrum the hump of the frequency makeup of the difference file is now centred at 1kHz, which is probably worse from the audibility POV -- still not happy!

Next step, do my own resampling of the 352 version, down to 96, then back up gain to 352, see what I get ...

Frank
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Old 29th December 2012, 05:21 AM   #31888
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Especially output stages, but common cathode simple stages as well. It is very audible, but who cares?
It is nonsense, Pavel. You repeat others' words.
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Old 29th December 2012, 05:24 AM   #31889
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No, that is not the main reason, Wavebourn.
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OK, time is up. The reason they bootstrapped the input resistors is to reduce effective input CAPACITANCE, in order to reduce distortion.
No way, John. Bootstrapping the resistor you are getting higher dynamic resistance. If you want to get lower gate-source capacitance you need to bootstrap the source, not the resistor.
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Old 29th December 2012, 05:54 AM   #31890
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Quote:
Originally Posted by fas42 View Post
Better nulling by applying an attenuation of -0.23dB to the 352 version, that's such a nice, obvious figure! So get a more reasonable looking balance at that precise point of the waveform. The trouble is, just down the road again there is some excess energy happening at other frequencies, as in the 2nd image.

Also, looking at the spectrum the hump of the frequency makeup of the difference file is now centred at 1kHz, which is probably worse from the audibility POV -- still not happy!

Next step, do my own resampling of the 352 version, down to 96, then back up gain to 352, see what I get ...

Frank
OK Keep going... we're listening and watching.
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