4. CROSSOVER SETTINGS
23
4.1 MINIMUM IMPEDANCE LOAD
The output stages of the RODEK R680A2 multichannel amplifier
are designed to give you extraordinary output power into 4 or 2
Ohms loads in normal stereo configurations. In bridged mode,
the minimum impedance load is 4 ohms. We put emphasis on
the fact, that the amplifier might suffer from thermal shut-down
or even damage, if these recommended minimum impedance
load ratings are not considered appropriately.
4.2 SELECTING THE OPERATION
MODE
The R680A2 is multi-channel concept amplifier with integra-
ted active crossovers and thus, offers different amplification
modes which can be set by the operation mode slide switches.
Three of these switches can be found on the R680A2 amp.
These switches enable you to configure each stereo channel
pair to work in either in fullrange, highpass or even bandpass
mode. Therefore - before you get started with the settings of
crossover frequencies and input gain adjustments - you must
select the appropriate operation mode for each channel pair of
your RODEK amplifier, depending on the speaker system that
is connected and driven by the amp. This will make sure that
every speaker system is only working in its proper frequency
operation range, for which the speaker was designed. For
example select HIGHPASS, if the speaker is a component- or
coaxial type, or BANDPASS in case of a kickbass or subwoofer
system - and finally FULL(range) if the passband frequency of
the stereo channel is already controlled by a head-unit with
an integrated DSP based active crossover.
4.2.1 HIGHPASS FOR COMPONENT
AND COAXIAL SPEAKERS
Before you start your adjustments, all tone controls (i.e. Bass,
Treble), fader/balance and loudness featured on the head unit,
must be set to their respective neutral or center position.
Please take a look at the chart below, featuring the sugges-
ted high-pass cross-over frequency settings for coaxial- and
component speaker systems - and adjust the highpass control
of each channel pair that drives satellites speaker systems
accordingly. The most important factor for the individual adjus-
tment of the highpass crossover frequency is the reproduction
of mid-bass frequencies and the resulting power-handling of
the speaker system. This setting is always a compromise. Try
to find a highpass crossover point, that will suit your personal
listening preferences and - at the same time - also considers the
physical (cone excursion) capabilities of your speakers best.
Satellite speaker system, front door mounted, recommended
highpass frequency
10 cm Coaxial- or Component System
90 - 120 Hz
13 cm Coaxial- or Component System
80 - 100 Hz
16 cm Coaxial- or Component System
60 - 90 Hz
Satellite speaker system, rear mounted, recommended
highpass frequency
10 cm Coaxial- or Component System
100 - 150 Hz
13 cm Coaxial- or Component System
120 - 150 Hz
16 cm Coaxial- or Component System
130 - 150 Hz
R680A2 MD.indd 23
R680A2 MD.indd 23
07.07.2004 12:36:46 Uhr
07.07.2004 12:36:46 Uhr
