APX_DPX Amps.qxd 2/6/2008 11:53 AM Page 20
English
7.Turn the volume back down slightly.
8.Slowly increase the gain control (clockwise). Stop when you hear a slight audio distortion.
When the gain is properly set, you should achieve maximum undistorted output with the volume turned up all the way, not half way.
If an oscilloscope is available, monitor the output of the amplifier with the scope, watching for clipping of the waveform. Set the gain so that only minor clipping occurs.
Adjusting the crossover
The APX2181, APX4361 and DPX2251 amplifiers feature
The DPX1851 and DPX11551 do not have a way to disable the
1.On the APX2181, APX4361, and DPX2251, use the
2.Using the Frequency (Hz) selection control, select the frequency.
Setting the bass boost
1.Initially set the bass boost control to the OFF position.
2.Listen to a variety of music styles (for example, rock, rap, etc.) and switch the bass boost control on until you notice an increase in low bass response.
Note:
Using the bass boost requires the amplifier to produce a great deal of additional power. Use bass boost sparingly.
CAUTION
If you hear a pop caused by speaker overexertion, lower the bass boost to prevent damage to the speaker.
Final system checks
1.Start the engine and turn on the source unit.
2.After a
If you hear any noise, static, distortion or no sound at all, check the connections and refer to Troubleshooting. Depending on your system, the volume may become quite loud even at moderate volume control settings. Until you get an “audio feel” for the system’s power, use care when adjusting the controls.
3.Turn the balance controls to their extreme positions and listen to the results. Audio output should match control settings (audio from the left speaker when balance is left).
20