I would hope so, I have a fine Bob Ludwig mastering job (George Crumb) that has easily heard pre-echo at some particularly loud transitions. I would assume it was on the tape and not removable. Your link is a little confusing not making it clear whether is is in fact not possible to cause print through on the acetate which of course would be transferred to the stampers and then to the the actual vinyl copies.
EDIT - Sorry I have to take the cheap shot, for once you do have to be deaf not to hear it.
EDIT EDIT - There is a long thread on Steve Hoffman's forums, no definitive clarification. Steve says it's a mastering problem Jerry Kramer and Glynn Johns (?) have had it happen to master tapes too.
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If the vinyl master has lands too small the pressing shows the pre-echo. Both mastering and production process will impact the issue. It can even happen with metal mastering. On the old high volume plants the temptation to look the other way was high. Getting more content on a side was more important than audio quality. Especially if the return rate wasn't too high.
I still think this was not the presenting issue that started this discussion of prehistoric manufacturing.
I still think this was not the presenting issue that started this discussion of prehistoric manufacturing.
If a traditional chain including proper antialias filtering and good downsampling is used and real acoustical signals were recorded without heavy digital rework, i´d certainly agree, but as stated before, if heavy processing is incorporated there is no protection against "unusual" waveforms ensured; means against waveforms that could never have occured via the traditional chain.
Appendix:
Reduced pre echo effects was one claimed advantage of the DMM process which would mean the laquer cutting is one/additional source of pre echoes.
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I appreciate that it's a real concern, but do we have any known examples of such violations actually making it out to a commercial disc?
Ref the intersample overs. On a redbook CD has anyone an example that produces an audible effect? None of the review primates has ever noted this so either
1) They are deaf and can't hear it
2) One oversample in 60mins isn't noticable
3) They wont hear it until a vendor FUD's up the issue explaining how their new wonderbox cures it.
1) They are deaf and can't hear it
2) One oversample in 60mins isn't noticable
3) They wont hear it until a vendor FUD's up the issue explaining how their new wonderbox cures it.
As for occasional ticks and pops, they have a hard time creating a "sound". BTW the over has a hard time being ON the CD it can only happen in the post processing. Maybe that explains the popularity of NOS DAC's.
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Plenty of folks that should know better state the same thing without actually examining the issue. The guys from Channel D had their way of looking at it. I would simply have surveyed the crest factors of a wide selection of LP's.
As for occasional ticks and pops, they have a hard time creating a "sound". BTW the over has a hard time being ON the CD it can only happen in the post processing. Maybe that explains the popularity of NOS DAC's.
The overs were just an example to illustrate that it was/is in fact quite simple to get signals in the system/chain that are able to cause.......
In this regard the signals are already _on_ a cd although the real magic happens later.
The "error mechanism" seems to be quite straight forward. Manipulation or creation of signals in the digital domain is simple but often no "big brother" is watching if these signals violate the boundaries of the system.
Intersample over issue is discussed here by John Siau, a little over half way down the page: https://benchmarkmedia.com/blogs/ap...k-dac2-vs-dac1-is-there-an-audible-difference
Also, he provides links to some other articles.
Also, he provides links to some other articles.
Everything seems obvious once you know it. There would seem to be multiple possible sources for echos in recordings. Not obvious which you were referring to.
In this regard the signals are already _on_ a cd although the real magic happens later.
Kind of amusing to worry about this considering how many pop CD's have not infrequent hard clipping. I mean with this, why bother?
http://baselaudiolab.com/TRK15_4_47B.jpg
I read through the articles, and I'm still left wondering how frequent these inter-overs are. If there's one sample per track, or 10 per disc, then how much should we worry? I've heard some mp3's where it gets screechy (could have been a number of reasons, but let's assume all inter-overs), but not on a CD. Not saying it's not there, but how much is this a real vs. ostensible problem?
(I'm speaking generally, not specifically all in reply)
Since the artifacts they create are high frequency noise bursts, maybe people who don't hear HF as well as they once did, or people with noisy DAC/headphone amp type of equipment may not notice much.
If anyone really wants to find out how commonly it occurs on commercial CDs, there are intersample over detecting VU meter plugins for VST recording host programs. Rip the CD track you want, import it into VST host (with host project sample rate set to 44.1, so no unintended SRC), and see for yourself. Personally, I am feeling too lazy today to do any free research. But, I look forward to hearing your results.
It strikes me as a trivial issue to resolve. Basically use DSP to reduce the digital level 3 dB and make it up on the analog side. The analog levels are pretty arbitrary anyway. I have heard a quick way to boost perceived performance is to just have more output. . .
The inter-over stuff became obvious a long time ago at Phillips I was told. Their early oversampling chips did not scale the level so the peaking in the digital filter cause clipping.
I looked for clipping on some current pop stuff. Curiously there was lots of clipping BUT at typically -1 dB or so. Never at FS.
The inter-over stuff became obvious a long time ago at Phillips I was told. Their early oversampling chips did not scale the level so the peaking in the digital filter cause clipping.
I looked for clipping on some current pop stuff. Curiously there was lots of clipping BUT at typically -1 dB or so. Never at FS.
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