JDS Labs Objective2 Operating Instructions

1. Connect an audio source to the Input jack using a 3.5mm interconnect cable.
2. Connect headphones to the Output jack.
3. Press the Power button to power on the amplifier. Keep volume low until music is playing.
4. Slowly raise the volume knob to an appropriate level. See Listening Tips below.
Listening Tips
 Always use low gain, unless maximum volume is insufficient with your specific equipment.
 For maximum sound quality, use a line level source, or turn your audio player's volume up very high
(60‐80%). Volume should always be controlled from the amplifier.
 This amplifier can produce dangerously loud music. Be sensible and listen safely: www.hearingloss.org
Troubleshooting
O2 produces no sound, but power LED is on

Cause: Batteries are weak.
o
Solution: Turn the O2 off and recharge.
o
O2 turns off unexpectedly and/or produces clicking or popping sounds

Cause: Batteries are weak.
o
Solution: Turn the O2 off and recharge.
o
O2 does not charge, charges only 1 battery, or clicks while connected to power adapter

Cause: Incorrect power adapter.
o
Solution: Use a 14‐20VAC power adapter. See notes on reverse side.
o
Distortion at high gain

Cause: O2's volume control resides between its input and output stages. Some combinations of
o
headphones and line‐level sources can overdrive the O2's input stage. Refer to NwAvGuy's blog
for thorough explanation.
Solution: Use low gain, or switch to a high voltage AC adapter.
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Thank you for purchasing the Objective
at: contact@jdslabs.com
Objective
. If you have additional questions or comments, feel free to contact us
2
Headphone Amplifier
2
Operating Instructions
JDSLabs
.com