[Ardour-Users] click free editing and zero crossings?

[John Rigg]

On Thu, May 20, 2010 at 12:49:22PM +1000, Ross Johnson wrote:
> There is also the theory/fact that, because almost any splice, at zero  
> or any other matched level, will introduce some discontinuity (i.e. some  
> harmonic artifacts), then it is better that it occur at the zero level,  
> where the level of those artifacts will also be zero or at least minimal.

The artifacts will actually be non-harmonic as the discontinuity
is a single event.

The important thing is to avoid a discontinuity. This will occur
if the sample value and the _slope_  (equivalent to dv/dt in analogue
voltage terms) of the signal are not matched at the point of the
join.

It doesn't matter if the discontinuity in the spliced signal occurs
at a zero crossing or anywhere else, it will still produce an impulse
of a similar magnitude.

John