26 - Distortion Measurement of Swift-IIIc
(mic 20 ins On Axis with Tweeter | 5ms Impulse Window | 1/12 oct
acoustic slopes of Swift-IIIc drivers are shown in Fig 27.
Disregard readings below 400Hz as room inteference takes
over. For the lowest distortion, the 18dB/oct filter for
the ZA14 has been retained. The XT25TG30, on the other hand,
is now filtered with a 12dB/oct network (Red trace). The
crossover summation is in fact, smoother than Swift-IIIb.
27 - Swift-IIIc Frequency Response
(mic 1 meter Tweeter Axis | 5ms Impulse Window | 1/12 oct smoothing)
Disregard readings below 400Hz
crossover network of Swift-IIIc is shown below (Fig 28).
What is glaringly obvious is the omission of the LCR in
the tweeter's network. After more measurements and auditioning,
I found the LCR doesn't really contribute to better sound
quality in this instance.
28 - Crossover Network of Swift-IIIc
Auditioning Swift-IIIc (Ultimate-II)
the Swift-IIIc an improvement over the rest?
listening to it for a few days, I would vote a resounding
YES. It is not just a smoother crossover summation but rather
one of coherency. Maybe I'm sensitive to phasing. The Swift-IIIc
simply sounds "in-sync". The net effect is the
music sounds more natural.