There seems to be continued confusion on how Klippel NFS works. The system absolutely does NOT care what the source looks like. I don't tell it for example that a speaker is 2-way, has ports, where those are, etc. All I tell the system is the boundary of the speaker so it doesn't attempt to drive the microphone and hit it. The speaker is a black box that generates a spherical waveform that the system attempts to compute by taking many samples around the speaker and solving a set of equations that can then be used to compute the sound field in any point in space.

Here is a simple analogy. Let's say we have a perfect amplifier. It outputs what it is input but with gain. If we plotted its response, it would look like a flat line line these:

If we sampled the system at two X/Y points and then drew a line between them, then we could predict the output for any input, not just the two we measured.

** Importantly, we would not care what the system is.** It could be an amplifier or a car steering system. If it is linear, those two points will be enough to fully describe its function across infinite points. The equation we would have solved is Y = A * X. "A" gives us the slope and that is all we need here.

Now if the system is not linear, then we would need an equation with more terms in it to describe it. The more complicated the response, the higher number of parameters (coefficients) we need. Within some accuracy error, if computational power and number of measurement points are high enough, we could solve just about any system response. This is how Klippel NFS works in a nutshell.

Note that even a simple box speaker is not a simple source. Diffraction, ports that can be anywhere, etc. are all sound sources that combine into some complex waveform that travels in space. Ironically, the worse the speaker is, the more complex its waveform becomes as it has many sound sources instead of a clean point or plane wave.

As I showed in the outset of this review,

**Klippel NFS system is self-checking. ** It will sample and compute the soundfield. But then compares the computed soundfield to real measurement points in the 3-D space and compute the difference. If the difference is small, you are assured of accuracy. There is no process of computing and praying the measurements are accurate. We know how accurate they are.

So back to the question of dipoles, no, it makes no difference to Klippel system that a speaker is dipole or not. It simply generates a soundfield that is sampled and wave equations solved for it. That said, complexity of the soundfield did become great in upper treble:

Fortunately the bulk of the issues we see in Magnepan LRS are at lower frequencies where the accuracy is way below 1%. And even above, the overall picture is correct:

So please don't ask if "klippel took into account a dipole speaker." The math doesn't care any more than a Dyno would care what engine technology it is measuring the horsepower and torque for.