Theta Digital Casablanca IV Owner'S Manual Download

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Dirac Live® 96 kHz Setup

In a 2002 article in

The Audio Critic

, Dr. Floyd Toole, then Vice President, Engineering for Harman Industries

wrote: “The room is the final audio component. Rooms audibly modify many aspects of sound quality. All rooms
are different.” Dr. Toole went on to say

, “Accurate high-resolution in-room measurements along with acoustical

corrections and equalization are necessary to deliver truly good sound to listener’s ears in homes and in studios.”

Dirac Live® is a state-of-the-art measurement and room optimization suite that finally allows users to follow Dr. Toole’s
admonition. We recommend that initial setup of your Casablanca IV be done without using Dirac Live®. After proper
operation of your basic system has been verified, please see Appendix F for details on Dirac Live® set-up.

Once Dirac Live® data acquisition is complete, please use the actual in-room performance data and revise crossover
points and slopes where necessary.

Dirac Live® set-up is covered in Appendix F

Speaker Configuration & Crossovers

Crossovers are most commonly located in a speaker cabinet. Their purpose
is  to  keep  energy  at  certain  frequencies  from  reaching  specific  speaker
elements (drivers), [e.g. keeping unwanted bass energy from the tweeters
(see  diagram  at  right).]    Home  theater  applications  use crossovers  in  the
surround processor to send low pass information to a subwoofer and limit
the low pass information sent to the main speakers.  The purpose of this
section,

SPEAKER CONFIGURATION

, is to properly set up the Casablanca

IV’s internal crossovers for optimal sound as well as enable all speakers in
the system.

In this manual, a Speaker Set is defined as one or more speakers that are
manipulated via a common parameter. For example, the crossover
parameters for both the front left and right speakers are manipulated in the front left/right configuration submenu since
the desired effect for the left speaker is also appropriate for the right. The other speaker ‘sets’ in the Casablanca IV are
the [surround left and right], the Back [bacl surround left and right], and the [center]. The speaker sets will be delimited
by [ ].

Full speaker configurations are stored separately for each of the 12 input select buttons. This procedure will guide the
user to set all configuration parameters for input # 1, and then copy these parameters to all other input select buttons.

In the Speaker configuration submenu, buttons

will access additional menus to setup a particular speaker or set

speakers. Button

will turn on the back speakers, if configured in the system

Linkwitz-Riley

While previous versions of the Casablanca allowed for several types of crossovers, with the Casablanca IV only

Linkwitz-Riley crossovers are available.

The significant advantage of Linkwitz-Riley filters over all other filter types

is that Linkwitz-Riley filters exhibit zero phase difference between the high-pass and low-pass filters at all

frequencies. They always match.

Linkwitz-Riley Crossover Diagram

A note on crossovers

Selecting  crossover  options  can  at  first  appear  daunting.    Traditionally,  crossovers  have  been  set  by  reading  the
specification sheet for one’s loudspeakers, noting the reported cut-off frequency and using that information to choose
the crossover frequency. The Casablanca IV is rare:  the inclusion of Dirac Live® 96 kHz gives the calibrator the exact
in-room response of every speaker in the system and allows improved selection of crossover frequencies.