Level Adjustment
New School –
Required items: Digital Multi-Meter, Test track media @ 1kHz and 100Hz. Max Amplifier Line-level Input Voltage Specification (i.e., 4vrms, 8vrms, etc.)
Proper level adjustment is crucial for obtaining the best possible sound quality. Following the guidelines below will enable you to properly set the
output gain of the LP3-4 using equipment that is readily available. Although this device can be set by ear (Old School), we recommend using a multi-
meter and test tracks for pinpoint accuracy and the least chance of noise.
Amplifiers usually have 2, 4 or 8v max line-level input ratings but this can vary. This max line-level input will be your target setting you will read on the
multi-meter. Perform the following procedure for each amplifier you are installing.
Old School –
1. Start with gain adjustment levels on LP3-4 and amplifiers set to minimum.
2. Turn source unit to ¾ maximum volume and play a familiar song that has dynamic attributes.
For example, if your volume goes to 40 you will turn it up to 30 and play a song that has some
quiet sections and some really loud sections.
3. Slowly adjust front channel gain of LP3-4 until just a hint of distortion is audible, and then
back down gain just under that threshold and the distortion goes away.
(figure 2)
4. Repeat steps 1-3 for rear channels.
_
+
Figure 2
Example:
Amplifier 1
(Mid/High frequency)
has a maximum 4v input voltage, so you will be targeting a 4
volt output voltage from the LP3-4.
Amplifier 2
(Sub frequency)
has a maximum 2v input voltage, so you will be targeting a 2 volt
output voltage from the LP3-4.
1. Start with gain adjustment levels on LP3-4 and amplifiers set to minimum.
2. Turn source unit to ¾ maximum volume and start test track
(1kHz for mid/high or full range, 100Hz for sub).
3. Choose either left or right channel - With multi-meter, test output of LP3-4 front
channels. Probe with negative on RCA shield and positive in center of RCA output.
(figure 1)
4. Slowly adjust level on LP3-4 until you reach the target voltage of the amplifier.
(figure 2)
5. Repeat steps for rear channels
(if connecting to a different amplifier, adjust to that amplifier’s voltage requirements)
6. Turn volume down and system off.
7. Connect RCAs, set gains on amplifiers to minimum
8. Turn system on and fine tune gains of amplifier
(if needed)
.
Note:
If using large RCA connectors and have difficulty inserting into housing, unsnap the
L.O.C.PRO™ cover and remove insert around RCA outputs.
Figure 1
Set meter to AC voltage.
Connect Red probe to Voltage (V)
Black to Common (COM)
AUDIO ACCESSORIES
PAC ELECTRONICS ACCESSORIES
