Re: [ARSCLIST] Pitching and Equalization of 78s/Resampling questions.

[Goran Finnberg <mastering@xxxxxxxxx>]

Aaron Luis Levinson wrote:

> that things like "time compression and expansion functions" are almost
> never employed in modern sessions because despite what the math may
> indicate there are very ugly and noticeable artifacts that emerge from
> these
> algorithms.

Time twist which is one of the names used for this type of operation ie
changing the pitch without changing the tempo can be quite audible since
it´s difficult to find good splice points to give an unbroken flow of
tempo.

Varispeed on the other hand is exactly akin to changing the speed of the
motor driving the turntable which will change both tempo and pitch which
is exactly the errors we have on the original recording.

In a digital system we do varispeed by changing the system clock to
increase or decrease the speed.

This is called sample rate conversion and is in the better software and
freestanding boxes a completely transparent operation in my experience.

> This immediately produces more "grain" because now half the number of
> samples are being used
> to replicate the same sound.

No.

You´ve gone from 16 bits to 8 bits quantization.

But the sampling frequency is unchanged in your example.

> However unless I am radically mistaken this
> down-sampling did not shorten (or extend )the sample from a time
> perspective.

Right, since you´ve changed the bit depth and the sampling rate is
totally unchanged.

You´re mixing two totally different concepts, sampling frequency with
the number of bits used to describe the samples.


--
Best,

Goran Finnberg
The Mastering Room AB
Goteborg
Sweden

E-mail: mastering@xxxxxxxxx

Learn from the mistakes of others, you can never live long enough to
make them all yourself.    -   John Luther