Hardware Detail
FIGURE 2-9 LED INDICATOR
2.10 Volume Control
No potentiometer is provided for manually adjusting the volume. The volume control of
sound source like MP3 player or PC can be used to adjust the loudness of the audio
output or a 50K
Ω
potentiometer can be installed by users themselves, but it may cause
signal attenuation. To compensate that attenuation, adjusting the gain value is required.
You may refer to 2.7 Gain setting for details.
Please be aware that audio clippings may occur to some portable players because of
the audio source not the amplifier itself. Please increase the input gain of amplifier
board.
2.11 Notes
In order to protect amplifier board and extend its service lifetime, please read the
following warnings carefully since warranties will be voided if you do not observe the
following warnings:
Warning 1:
Quality-related issues caused by potentiometers installed by buyers.
Warning 2:
In order to achieve a better sound quality, please use stable power supply since a bad or
unstable power supply may worsen the sound quality or even cripple the amplifier board.
Warning 3:
Never equip a pre-amplifier to the audio input since the amplifier itself has powerful
amplification ability and a high signal input will burn out the amplifier chip.
Warning 4:
In order to protect amplifier and speaker, please turn the volume output to the minimum
when hooking up the amplifier and you may readjust the volume when you are sure that
the amplifier is functioning properly.
©
2004-2009 Sure Electronics Inc.
AA-AB018_Ver1.0_Page 11
