Question re copying cassette tapes

[Aidan Wilson]

If you're "creating an audio CD" using iTunes or indows Media Player, then 
sure; it'll do all the converting for you, but this is potentially 
sub-optimal, as you may be creating a CD from mp3 files. These programs 
will happily expand them out to CD-Audio WAV specifications in the 
formatting and burning process, but needless 
compression/expansion/transcoding should be avoided.

I was thinking along the lines of manually formatting a bunch of audio 
files using Audacity or something, and using a program like burn (on a 
mac) or Brasero (on Linux). There must be a similar program for Windows - 
the point is there should be a checkbox for 'audio CD' - but I haven't 
used Windows in some time.

On the tangential issue running alongside this thread, yes, the higher the 
better when it comes to audio quality, and only transcode at the last 
minute. If you're digitising something and turning it into an audio CD for 
instance, do all your bits and pieces to the files, normalising, EQ, noise 
filtering, etc. first. Resampling and dithering to 44.1 at 16 should be the 
very last operation.

Bill maintains that the human ear is incapable of discerning frequncies 
above 22000 kHz, and that may well be true, but the human brain is capable 
of hearing quantization at that speed. As a test, take a 44.1 kHz file and 
slow it down by half using ELAN or something - you'll hear choppy 
playback. If you do the same to a 96 kHz file the effect is nowhere near 
as noticeable.

-Aidan

On Thu, 11 Feb 2010, Neskie Manuel wrote:

> I would record at the highest rate even though, as Bill points out,
> that it is a waste of space. Terabyte Hard drives are the norm.  If
> you are worried about space make sure you compress with a lossless
> compressions such as FLAC, programs like Audacity can do this
> natively.  Audacity also has a timer for the record function so you
> can set it to record for 30 minutes, and it is available for Linux,
> Mac, Windows. This list is ordered for a reason ;)
>
> I don't think it really matters when burning to a CD what sample rate
> you use, because programs like iTunes or Windows Media Player usually
> upsample and convert to a WAV before the burn it to a CD anyways.
>
> On Thu, Feb 11, 2010 at 3:57 PM, Aidan Wilson <aidan at usyd.edu.au> wrote:
>> While I disagree about the benefits or otherwise of higher resolutions and
>> sample rates in digitisation, the point is, that an audio CD must be stereo,
>> 44.1 kHz, 16 bit.
>>
>> Anything else will not play on any regular CD player (that is, which isn't a
>> computer that can interpret the wav header). The reason is that audio CD wav
>> files don't contain headers; they're raw PCM data - 1s and 0s. CD players
>> are designed to interpret those 1s and 0s as stereo, 16 bit 44.1 kHz.
>> Altering the properties, if it plays at all, will have effects on the audio
>> such as playing too fast/slow (if the sample rate is incorrect) or just
>> outputting digital noise.
>>
>> --
>> Aidan Wilson
>>
>> The University of Sydney
>> +612 9036 9558
>> +61428 458 969
>> aidan.wilson at sydney.edu.au
>>
>> On Thu, 11 Feb 2010, William J Poser wrote:
>>
>>> I'm not so sure about the recommendation of stereo digitisation. If
>>> the originals are not stereo recordings, there's no point in creating a
>>> stereo digital recording, and indeed, even if there are two channels
>>> on the original tapes, if they do not reflect inputs from two different
>>> microphones, you don't have a true stereo recording and there isn't much
>>> point in preserving two channels.
>>>
>>> Also, 44.1 K samples/second is overkill for most linguistic material. If
>>> it contains music, such a rate may be desirable, but for most speech,
>>> 22.05 K samples per second includes all of the information likely
>>> to be of linguistic significance.
>>>
>>> 16 bit resolution is highly desirable, but there's nothing sacred about
>>> 44.1K samples/per second sampling rate and stereo. These are merely
>>> residues of decisions made by the music industry and have nothing to
>>> do with the quality of linguistic recordings.
>>>
>>> Bill
>>>
>>>
>>
>
>
>
> --
> Neskie Manuel
> http://neskiemanuel.ath.cx
> Voicemail: 1 (866)-423-0911
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>