Apogee DAX 3 Owners manual

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POGEE

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COUSTICS INC.

DAX 3

Dedicated Active Crossover

Owner’s Manual

INTRODUCTION

The DAX 3 is a two channel Dedicated Active Crossover designed specifically to be used with the Apogee
Acoustics Diva, Duetta Signature, Caliper Signature, and Centaur Major speakers. It provides exceptional
tuning flexibility, which enables users to sculpt a tonal balance to meet their exact listening requirements. The
DAX will accommodate a wide range of preamplifier and amplifier characteristics.

Features of the DAX 3 include woofer and midrange/tweeter level controls, fine level adjust controls, and rake
angle level adjust controls. These controls facilitate ergonomic operation and easy adjustment. The rake angle
control provides proper integration of the speakers' midrange/tweeter transducers with the audio system and
listening environment. The DAX 3 is capable of operating with single-ended or fully balanced input-output
signal interconnects. Input impedance adjustment controls fine-tune the matching characteristics between
DAX 3 and most available pre-amplifiers. Selectable amplifier gain matching provisions ensure total system
compatibility.

INSTALLATION

WARNING: DISCONNECT ALL POWER AND CABLES TO THE DAX BEFORE MAKING ANY
ADJUSTMENTS!

1) DAX ADJUSTMENT SWITCHES (See Diagram #1)

Inside the DAX are two output printed circuit boards for the left and right channels. There are a number of
switches on each output board which are used to select gain settings for matching amplifiers with different
output levels, filter shapes for the selected Apogee loudspeaker, balanced or single-ended inputs, and various
input loading settings.
If your authorized Apogee dealer has already performed these adjustments for you, proceed to section 2.

REMEMBER!: WHEN ADJUSTING SWITCHES ON DAX OUTPUT BOARDS, CONCURRENT
CHANGES MUST BE MADE FOR LEFT AND RIGHT CHANNEL OUTPUT BOARDS!

Amplifier Gain Matching

Make sure that no cables, including power cord, are connected to the DAX.

Remove the top cover of the DAX main unit by removing ten machine screws with the allen wrench
provided. Viewing the printed circuit boards from the front of the DAX, 4 printed circuit boards wilt be
visible: two smaller printed circuit boards attached to the front panel and two output printed circuit boards,
one left channel, one right channel, attached to the rear panel.

Locate switch #6(SW6) & switch #7(SW7), towards the left center of the output boards (Refer to Diagram

1). These switches allow matching amplifiers with different gains. Please consult your power amplifier
manual or manufacturer for this information.

SW7 attenuates the woofer level in 1 dB steps from 0 to -6 dB. SW6 attenuates the midrange/tweeter level in
1 dB steps, as well. For example, if you are using a power amplifier with a 20 dB gain on the woofer and
another power amplifier with a 23 dB gain on the midrange/tweeter, you would attenuate SW6 to position
number 3 which corresponds to -3 dB.

Speaker Selection

Switch #3(SW3) is used to select the appropriate filter shape for one of the two available speakers. Please
check the inspection certificate in the DAX packing carton with the factory preset values to make sure you
received the correct speaker model selection. SW3, on the middle right edge of the printed circuit board, can
be toggled to the left for Speaker A or to the right for Speaker B. Refer to Table 1 for the Apogee speaker
designation depending on the two speaker choices received.

NOTE: This must be done for both output boards!

TABLE 1

Speaker Combination

Speaker A Speaker B
Duetta/Diva Duetta Signature Diva
Caliper/Diva Caliper Signature Diva
Centaur Major/Diva Centaur Major Diva

Balanced or Single-ended Input

Switch #2(SW2) is used to select either balanced or single-ended (regular RCA) input. SW2 is located right
above SW3 on the right edge of the printed circuit board. Toggled towards the right, or nearest edge of the
board, selects the single-ended input. Toggled to the left, or away from the nearest edge of the board, selects
the balanced input.

Both single-ended and balanced outputs are operational at all times so any combination may be used.

Impedance Loading (See Table 2)

Switch #5(SW5) is used to select the input impedance loading for the single-ended input. Switch #1(SW1) is
used to select the input impedance loading for the balanced input. SW5 is located in the upper right hand
comer of the printed circuit board as you face the front of the DAX. The label is not visible on the printed
circuit board, as it is hidden under the switch. SW1 is located to the left of SW5. There are four small rocker
bars in the switch, labeled 1-4. Only one toggle position is used for each setting. Be sure the other switches
are OFF. The DAX is preset at the factory for 80,000 ohms, single-ended, and 10,000 ohms, balanced (All 4
rockers in the OFF position).

Consult the manufacturer of your pre-amplifier or signal source device to determine the impedance
loading that the device works best with. Most manufacturers have conducted extensive tests on the
effects of impedance loading and should be able to answer this question. Select an impedance loading
value equal to or greater than the manufacturer's recommendation. If you cannot obtain a satisfactory
recommendation, choose the highest impedance setting for use with tube equipment or mid-value setting
for solid state equipment..

TABLE 2

Switch #5(SW5), Single-ended Switch #1(SW1), Balanced

Rocker #(ON) Value Rocker #(ON) Value

#1 5,000 ohms #1 600 ohms
#2 10,000 ohms #2 1,200 ohms
#3 20,000 ohms #3 2,500 ohms
#4 40,000 ohms #4 5,000 ohms
#1-4 OFF 80,000 ohms #1-4 OFF 10,000 ohms

2) Required Wiring Modifications to Apogee Loudspeakers for Use With DAX 3

The following speaker wiring changes must be performed to permit operation of the Apogee speakers
with the DAX active crossover. The wiring changes are simple and readily performed.

WARNING!: BEFORE MAKING ANY WIRING CHANGES, DISCONNECT ALL POWER TO
THE AUDIO SYSTEM.

DIVA (See Diagram #2)

The Diva is a three way speaker and the DAX is a two way active crossover. It is necessary to use the
standard Diva passive crossover for the tweeter. The tweeter HI, LOW, NORMAL switch remains active
while the rest of the switches are not.

The DAX comes with a modification kit for the Diva passive crossover when purchased for use with the
Diva. The kit includes (2) midrange coils designated "L5", (2) WHITE wires for woofer ground, (2)
GREY wires for midrange ground, a 3/8" socket wrench for removing the nuts on the binding posts, and
an allen wrench for removing the bottom cover of the passive crossover electronics box. If your Diva's
serial number is before #10360, a small amount of soldering is required and you will need at least a 40
Watt soldering iron to continue.

WARNING: IF YOU ARE NOT MECHANICALLY INCLINED, HAVE YOUR APOGEE
DEALER PERFORM THESE MODIFICATIONS.