[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [ARSCLIST] Lossy compression losing quality (was Re: [ARSCLIST] Pristine Audio and the Milllennials . . .)
At 11:49 PM 2007-12-11, Howard Friedman wrote:
When a recording company transfers music from, say, a 78rpm,
acoustic or electric, to a CD, what file format does it actually transfer?
How does one get from 78 or LP to WAV? Not that I intend to, just curious.
Hello, Howard,
There are many web resources that discuss this at varying levels.
The very basic signal chain is this:
Playback device ---> Analog-to-Digital Converter
The Playback device in this scenario includes some processing.
For example, when playing a grooved recording, there are specialized
preamplifiers that boost the very low cartridge level to what is
called line level for input to the Analog-to-Digital converter (ADC).
That ADC, coupled with computer software creates WAV files on the
hard drives of the computer. These files are then edited and cleaned
using a variety of processes running on the computer and then a
master CD is burned.
Much "ingest" (copying from analog to digital) is done at 96,000
samples per second and 24 bits -- far higher resolution than the
audio CD. I just did a pair of1.5 hour concerts that ended up at
about 3 GB each -- I used 88,200 samples per second and 24 bits stereo.
Howard, perhaps we'd better be able to answer your questions if we
understood your background and applications better. All of us here
like to help people, but the questions you are asking are very, very
simple ones that could be answered by reading up on a number of
websites. We can't provide individualized tutorials -- however much
we'd like to -- to everyone who has just joined this list of
collectors and technicians who support these collections in one way or another.
While I do tape transfers (and leave discs to others), I'm very open
about what I do and have lots of hopefully useful information on my
website, including a list of equipment that I use to digitize analog
tape recordings and turn them into CDs or WAV or MP3 files for
storage on servers. One of the links will take you to my infrequent
Blog called "Tips and Notes". "Formats and Resources" is embedded in
the same subsite (see below for a starter link).
Please see www.richardhess.com/tape/facility.htm and navigate from
there. If you find something you don't understand, please try to use
Google to find a resource about the particular item.
You might go to www.magix.com and look at their $40 Audio Cleaning
Lab package and it's a miniature version of what many of us have.
Also www.tracertek.com has some useful information as well, I
suspect. There are many workflows. If you want to read in detail
about what is done by people on this list, try the recent Sound
Directions publication. It provides in-depth detail of everything
around the two questions you asked.
http://www.dlib.indiana.edu/projects/sounddirections/papersPresent/index.shtml
Cheers,
Richard
Richard L. Hess email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.