| From: | Martin Nicholson |
| Date: | 5 Aug 2000 at 00:54:32 |
| Subject: | Re: Mpeg 3 playback. |
Hiya greenboy
On 04-Aug-00, greenboy wrote:
> No. Think of converting a color-mapped picture to true color. If the
> conversion process is accurate the same colors are still
> represented. No accuracy gained or lost. The potential for more
> colors IS there, that's all.
Ah right :) Cheers. Basically then, as with most things, you can't get
out what you don't put in.
> Some will argue different and also talk about the effect of
> filtering higher frequency upon the phase of audible frequencies.
Which was what I was thinking about. Although not in such technical
terms :) I had read before that higher frequencies could/would cause
harmonics that were within the human's audible range. Anyway,
sometimes the bass doesn't have to be heard ... just felt :)
>> Thus 44100 KHz is about as high a samplerate as you need, and this
>> is adequately provided for by a 16 bit sample rate.
>
> All said, even moderately-priced pro setups may be working in 20-
> and 24-bit at 48 or 96 KHz sampling rates. Amigas are hopelessly
> behind in this field.
Yep :( Especially when you see the price of some of the PC cards :(
>> Of course, you could listen to Vinyl and then you would get an
>> infinite sample rate, as well as all those inaudible frequencies
>> below 20Hz and above 20KHz (which is why vinyl sounds better ;-) )
>
> Joke, right? Vinyl is a poor medium to dub "infinite"; it may be
> better described as troublesome, sporadic and random. As far as
> frequency response is concerned vinyl lathe and turntable playback
> process makes it grossly inadequate at low frequency response and
> linearity. And highs may sound somewhat "natural", but are incapable
> of the emphasis that CDs can routinely carry. Not to mention the
> lovely artifacts induced in manufacturing, shipping, storage, and
> playback. Screeetch. Bump. Scrsssshhh.
Erm, partial joke :) I still find some albums "sound" better on vinyl
than they do on CD. Basically, I think both systems have inherent
strengths and weaknesses. CD certainly has more versitality, in terms
of portability, etc, and convenience in it's operation. It definitely
has the advantage of a higher quality sound at it's budget level. All
the same, I think vinyl had some undeservedly bad press at CDs launch.
People were trying to compare £400 CD players, playing new disks,
against £30 turntables, playing old albums. Unsurprisingly, the CDs
sounded better. Later it became apparent, that you couldn't spread jam
and butter on a CD, clean it with a brillo pad and then play perfect
sound at all. I think it would be fair to say, that most people
haven't compared like with like, their turntables were generally cheap
and shoddy, compared with the bright shiny expensive CD player they
bought to replace it.
All I can say is, if I put an album on the Lenco Transcription deck
downstairs, it sounds very nice indeed. If the record has a couple of
scratches, to be honest you tend not to notice them; the music
overshadows them. The CD player also works very nicely too. But if the
CD is scratched, you might as well throw it out. Basically, I think
there's still a place for both systems.
As to the infinite bit, re: vinyl. What I was trying to get at is,
that most sounds you record are natural, and thus analogue; as was
vinyl. Thus, in a sense, it provides a truer recording of the sound,
since the digital recording is, at the end of the day,
on-off-on-off-on-......
>> Whats more important, at least so it seems to me, is the bitrate of
>> the mp3, i.e., whether it is 96, 128, 192, etc, KBPS. This, I
>> think, is the rate at which the mp3 encoding is sampling the
>> waveform of the wave sample. So that the mp3 isn't actually a 16
>> bit sample, so much as a bit rate, i.e., sampled so many times a
>> second (kpbs)? The greater the kbps is, the bigger the sample will
>> also be. An infinite bit rate would generate a massive file size.
>
> Both are important. Just as in bitmap pics, x-y resolution and color
> depth is important. High numbers (and good linearity in any
> conversion/ sampling processes) allow the sound or sight to be
> tailored more and less at the mercy of the format perceptually.
True. I meant in terms of varying the bitrate of the sample. I think
it has to be a given that your going to be, generally, using a 16 bit
sample and so the choice of the kbps becomes more important in terms
of choice, when encoding mp3s.
With Regards
Worzel
My grandma says she has eyes in the back of her head... I hope it's not hereditary.
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