6
Midrange & Treble: Once the lower octaves are sounding good, natural, vibrant midrange and treble can now be dialed in.
Before you begin I think it’s important to understand a few details. Midrange tuning, while similar to that of bass, is a task of a
inches (decimeters) rather than feet (half meters) and upper octaves a mater of half inches (centimeters) and loudspeaker fi ring
(wavefront) axis. Even though midrange and treble changes can be heard at the “being positioned loudspeaker”, it is helpful to have
a friend position while you listen in the seating area. Here, you may want to select less bass heavy recordings; jazz, space-ambient,
violin solos, guitar solos, stuff with good overtone color and not too heavy.
Staying with the same loudspeaker “room-tuned” for low frequencies, (remember you only tune one channel and mirror its mate)
and with your favorite less heavy recording playing, start tuning for mids and highs. Move it toward the closest wall, in increments
of a few inches (4 - 6cm). While moving, the “in the listening area” observer, and possibly the person positioning the loudspeaker,
should notice midrange color (presence) transition from low and masked to open and intimate. There may be several spots within
the good sounding bass area that have good presence, go with the widest point (closest to the wall) for an expansive and engaging
stereophonic soundscape, don’t worry about center focus, Defi nition Mk2 will do quite well with its capacity for expansive and
focused image recreation. Once a midrange position is selected it’s time to work on the highest octaves. This is usually as simple
as rotating the Defi nition Mk2 loudspeaker to face directly at the seated listener. Now listen again for voice openness and intimacy,
minor placement adjustments and face angle may be necessary. If it’s a bit too treble rich, rotate each speaker to focus behind the
main listening area a few feet. Experiment. And yes, this same technique works for the Presence and Druid loudspeakers.
Additional thoughts about playback, room, and tonality
Defi nition Mk2 overcomes so many problems with regard to room, attack, sustain and decay. All the attack of the complete audio
bandwidth and musical scale emanates from the front driver array. Bass through a bit of the midrange sustain and decay are
communicated by the rear woofer array; the proper place to make room correction and tone changes that won’t mess up attack and
the soul of the sound. Why? Because the attack, more than any other aspect of a waveform, gives the listener the clues to process
source, direction, amplitude, character, intelligence, and so on. Close in importance are the dynamics within, that immediately follow
the attack. A simple example: When a piano key is struck, three main components are set in motion. These make up the attack
of a note; the mechanical noises including that of the impinging hammer, initial string motion, which has many extra components
and initial coupling of piano body and sound-board. The fi rst few milliseconds are very dynamic and have many features. To get the
attack correct is solely a function of the playback system and has very little to do with the room. Aside from placement, if you have
changed your system to combat your room, attack and dynamics can never be correct. Most people can only pinpoint tonal problems
with steady-state or semi steady-state music or signal, this is a big problem because room infl uence on steady-state sounds are
huge, the single largest infl uence if included as a component of your playback system. So, people usually tweak things to get the
steady-state and decay tonally correct which inadvertently kills the life in the attack. This is a reason why cables as tone control,
digital room correction, parametric equalizers and the like can never “fi x” fundamental problems, unless of course the time axis is
also programmed and correlated to harmonic structure and then set to react to any dynamic anomalies within the signal, overlaid
with the room the original recording was made in and compared... how much are real super computers going for these days?
Bun-in
All Zu loudspeakers now come with at least 160 hours of real music conditioning at what we consider to be the right levels in our
burn-in rig. This puts the loudspeakers in a position to really sound good within a few days, great in a week or two and awesome
in the end. We do not recommend recordings specifi cally designed for loudspeaker, system or cable burn-in. The quickest and most
enjoyable way to fi nish the conditioning of your Defi nition Mk2 loudspeaker is to play music and movie scores that are fun, dynamic
and harmonically dense. No longer do you need to worry about cranking them up either. Let your neighbors know where they can
send tips, that’s Zu in Ogden, Utah....
Break-in Phenomenon: A running-in of driver suspension components is the prime infl uencing factor in loudspeaker break-in. Cable
burn-in is also a factor but secondary. Defi nition loudspeakers generally go through two break-in sound transformations. The fi rst is
mechanical effecting bass and intimacy. This is largely taken care of at the factory. The second is electrical and primarily effects tone,
stereophonic imaging and resolution. We start this process at the factory, burning in the drivers with the cable assembly at the same
time.
The following table is an approximation of Zu Defi nition Mk2 loudspeaker in-home fi nal burn-in playing at typical levels. Double the
hours for each if played at very low levels.
Out of the box, sound is good, a bit constricted and reserved; much worse if shipped in winter months. After fi rst 50 hours of play,
the fi rst week, sound should be much more present and extended in bass and treble. After 100 hours of play things should be very
open and alive with compelling transient accuracy. You know if you are liking them or not by this time. After 200 hours of play, they
should be nearly transparent, music should sound very relaxed yet be full of resolution and recorded detail. After a year you will
swear the Defi nitions have bridged the divide between heaven and hell. No this is no joke. The burn-in process we run the Defi nitions
Mk2’s through lays the groundwork for the evolution that was simply not possible prior to our development of the process.
