Test Procedures - Bose PACKLITE A1 Manual

3.2 Connect the output of the A1 to the
4 Ohm load resistor.
3.3 Power on the unit.
3.4 Apply a 1 kHz, -10 dBV (T to S) signal to
the input.
3.5 Reference a dB meter to the input level.
Measure the gain output at the load.
It should be +30.0 +4.0 dB.
4. Signal LED Test
4.1 Confirm that the green signal LED is on.
4.2 Lower the input signal to less than -25
dBV. Confirm that the green LED turns off.
4.3 Raise the input signal to over 1 dBV.
The LED should turn red.
Caution: Remove the input signal after this
test to avoid overheating the amplifier and
load.
5. Frequency Response & Distortion
5.1 Connect the signal generator to either
of the A1 input jacks with an unbalanced,
1/4" TS cable.
5.2 Connect the output of the A1 to the
4 Ohm load resistor.
5.3 Power on the unit.
5.4 Apply a 1 kHz, -10 dBV (T to S) signal to
the input.
5.5 Reference a dB meter to the input level.
Measure the frequency response at the load.
It should be 0.0 dB + 1.0 dB from 20 Hz to
20 kHz.
5.6 Measure the Total Harmonic Distortion
(THD) at the load. It should be less than
0.1% (0.02% typical) at 1 kHz.

TEST PROCEDURES

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6. Signal to Noise Test
6.1 Remove the signal generator and insert
a TRS test plug with a 600 Ohm termination
between tip and ring. See page 37.
6.2 Measure the output voltage across the
load resistor. It should read less than -60 dB
A-weighted, (referenced to 1 Volt).
7. Power / Fault LED Test
7.1 Connect the output of the A1 to the 4
Ohm load resistor.
7.2 Power on the unit.
7.3 Confirm that the blue LED comes on.
7.4 Apply a 1 kHz, -10 dBV (T to R) signal to
the input.
7.5 Short the loudspeaker output jack
(plus + to minus -).
7.6 Confirm that the blue power LED
changes to red. It will briefly change back
to blue every second or so as long as the
short is maintained.
7.7 Remove the short and power down the
unit.
8. Listening Test
8.1 Connect a line-level audio source (such
as a CD player) to the input jack.
8.2 Connect the output to a 4 Ohm full-
range speaker.
8.3 The audio output should sound clean
and undistorted.
8.4 Raise the input level until the green
signal LED turns red occasionally. The
audio output should still sound clean, al-
though some limiting may be heard.