2. analog
  3. 160855-86984

vinyl versus digital redux

Has anyone compared the sound of vinyl with the sound of digital converted from a vinyl intermediary ?

I am referring to 'rips' of vinyl made with high end, high quality vinyl playback systems, with
conversion to high resolution digital.
I find it nearly impossible to distinguish the two results.
The digital rip of a vinyl record sounds identical...or very nearly so...to direct playback of the vinyl.

If one has 'experienced' the foregoing, one might question why digital made without the intermediary of vinyl sounds so different from vinyl.   A detective story ?

We are talking about vinyl made by ADC (analog to digital conversion) of an amplified microphone signal and re-conversion to analog for output to the record cutting lathe, or from analog tape recording of an amplified microphone signal, and then....as above...via ADCl and back to analog for output to the cutting lathe.

Of course vinyl can be and is 'cut' (pressings made from 'stamper' copies the 'master' cut in lacquer) without digital intermediary.  Such practice is apparently uncommon, and ?? identified as such by the 'label' (production)

Has anyone compared vinyl and high resolution digital (downloads) albums offered by the same 'label' of the same performance ?  Granted, digital versus vinyl difference should diminish with higher digital resolution.   Sound waves are sine waves....air waves do not 'travel' in digital bits.    A digital signal cannot be more than an approximation of a sine wave, but a closer approximation as potential digital resolution (equating to bit depth times sampling frequency) increases.

If vinyl and digital well made from vinyl intermediary sound almost identical, and If vinyl and digital not made via vinyl intermediary sound quite different, what is the source of this difference ? 

Could it reside....I'll skip the sound processing stages (including RIAA equalization)...in the electro-mechanical process imparting the signal to the vinyl groove ?

Is there analogy with speaker cone material and the need for a degree of self-damping ?
Were self-damping not to some extent desirable, would not all speaker cones, from tweeter to sub-woofer, be made of materials where stiffness to weight ratio was of sole importance ?

Thanks for any comments.
seventies
atmasphere's avatar
atmasphere
12,164 posts
 
Atmasphere, what is wrong with digital signal processing assuming it is used correctly? I know it is easy to screw things up, done correctly.
Its easy to screw up is all! I prefer a minimalist approach, using as little as I can. The more DSP gets into the mix, the more it seems to harm the final signal. But my experience with DSP is limited to its used in recording applications.
Does playback (with or without digitization) of lp's made, say 40 years ago, from audio tape offer advantage over hi res digital transfers made today from those 40-year-old tapes ?
@seventies
Of course! Tape degrades from the day it was recorded. If you want the best sounding LP from tape, you cut the LP ASAP. You then have the lacquer plated ASAP- that's how you get a lively vivacious recording. If you wait 40 years, no matter what method you use, the master tape will sound a bit 'sleepy' compared to the day it was recorded!
Analog tape is surprisingly robust for storage. It is usage that degrades it.

@audio2design
This statement is false unless very special care is taken in storage which is quite rare! If the tape is polyester, it is prone to absorbing moisture which leads to shedding; trust me on this if a tape has gone too far you won't even be able to spool it off the reel. Think: goo
I am asking about LP's made decades ago from analog tape...whether these lp's preserve sound...particularly high frequency sound...better than does the tape itself.
Yes. LPs have a lifespan of nearly a century if stored correctly (normal humidity and temperature, upright, not too many on a shelf). Stereo LPs have bandwidth to 40KHz or so, tape does not.



audio2design
1,351 posts
 
Atmosphere, the op was referring to master tapes which in general will be stored properly for any media company of note and for which my comment applied.  Note my next sentence.

The biggest concern is break down of the underlying binder for the magnetic materials and the plastic substrate.


If they are stored properly which major media companies generally do, then they are rather robust. 40khz bandwidth is of little use when the mastering media can't match it. That's also 40khz with effectively noise reduction, i.e. RIAA equalization at high frequencies. 
johnss
616 posts
 
Have to side with Atmosphere here. He is correct. Would agree on the minimalist method of doing most things, and most of the major labels do have climate controlled storage conditions for their session masters. That is not to say many production or duplication masters tapes still get tossed.  Can't tell you how many times I have been to the loading dock of a major studio back in the day, and found pallets and pallets of tape waiting for the garbage truck to pick it up.... 

As for tape degradation, the SSS (sticky shed syndrome) was a major problem on Ampex 406/407, 456/457, scotch 226/227, and a few others.

After Quantegy stated they had fixed the binder problem I bought 4 new cases of 456 with the new and improved binder. They were good for the first few years, but after that they slowly degraded into sticky shed just like the earlier stuff. Ended up pulling the flanges off and tossing the balance of the remaining tape into the trash.

The earlier formulations never had this problem. Same with Scotch 206/207. Have 4 cases of 207, from the early 1980s, and it still performs like new.

Losing signal was normally not an issue.
 
mijostyn's avatar
mijostyn
8,570 posts
 
Atmasphere, it is my understanding that most of the old tapes have been digitized. Correct me if I am wrong but digital storage is certainly more robust. Once in numbers that "sleepiness" can be corrected with very modest EQ as well as doing neat stuff like getting rid of the tape hiss.
I am totally unfamiliar with DSP as might be used in the recording studio.
My experience is in using it on the reproduction side for correction and bass management. Given the variables involved in speakers, subwoofers and rooms the advantages are significant on this end.  IMHO it is always an advantage to hear and know what "flat" sounds like before modifying things to your liking. It is also a great learning experience hearing what different modifications do to the sound.
onhwy61's avatar
onhwy61
5,348 posts
 
master tapes which in general will be stored properly for any media company of note
Are you forgetting about the Universal studio fire in 2008?  Apparently, it's really hard (expensive) to properly store large amounts of media.

If you're considering long term storage, as in 50+ years, vinyl discs are probably the preferred method.  This is according to research done by the Library of Congress when deciding upon their long term archive needs.
More to discover