ATI Audio HDA600 User Manual

Page 3

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and output jacks. Individual direct inputs can also be configured as BALANCED MONO
inputs (HI-LO-SHLD = TRS) by moving internal jumper plugs PX01 to the BAL MONO
position and adding a jumper plug at PX02 to combine left and right output channels.
PX02 can also mono sum a single output if desired. (X in a part number indicates
channel 1 thru 6).

A SIGNAL PRESENT indicator for each output channel indicates at about 30dB below
nominal input levels. The HDA600 includes an internal bi-polar power supply that will
operate at 115 or 230VAC by changing internal jumpers. The power cord is a standard
IEC320 type that you can easily swipe from someone else if you lose it.

CONNECTIONS

Balanced inputs are connected with their HI to XLR pin2 or TRS -TIP and LO to XLR
pin3 or TRS-RING, Shields go to XLR pin1 or TRS-SHLD. Unbalanced input lines
should be connected with their center hot wire to XLR pin 2 or TRS-TIP and with the
cable shield to XLR pin 1 or TRS-SHLD. Be careful to observe HI-LO input polarity to
avoid monaural or center stage cancellation effects

The HDA600 is shipped setup for -10dBu nominal Program input level (+12dBu peak).
An internal jumper plug P2 may be moved to accommodate levels at +4dBu nominal
(+22dBu peak). To change P2, remove the top cover by removing the four upper Phillips
head screws (two on each side). P2 is located on the right side of the PC board directly
behind the volume control and has two positions; for –10dBu inputs move the plug to
the left, for +4dBu inputs move the plug toward the right. Ensure that no internal wiring
is caught or pinched, replace the cover and screws.

Use only TRS output plugs and stereo headphones. The use of TS plugs on mono
headphones shorts one headphone output to ground. Although this will not damage the
HDA400, it will load down the power supply and reduce maximum output levels to the
other output channels. Output TRS plugs should all be wired Left to TIP, Right to RING
and common to SHIELD.

CAUTION

The HDA600 provides a comfortable listening level of 1mW at around 12 o’clock on the
volume control for most headsets. The HDA400 is capable of driving many headsets to
DANGEROUS LEVELS over 120dB SPL. If you can hear distortion, it is TOO LOUD!
Levels near 120dB SPL can easily cause PERMANENT HEARING DAMAGE.