6.5Level meter and CLIP indicator
The green LED-indicators -13dB and 0dB (1) together with the red CLIP-LED (2) allow to monitor the output level, effectively avoiding overdrive conditions that lead to distortion and overload at the power outputs which could damage the connected loudspeaker systems.
-If the red CLIP-LED (2) shortly lights during program peaks, maximum non-distorted modulation is achieved.
-Continuous lighting or blinking of the red CLIP-LED (2) signals overdrive. In this case the input level has to be reduced.
-If the green LED indicator (1) does not light or is only briefly lit with the red CLIP-LED blinking at the same time, this signals the encountering of an overload or short-circuit condition at the output. In this case the impedance of the connected load has to be checked.
Caution During normal operation the red CLIP-LED should only light briefly and shortly!
7.Switching the output voltage (only to be performed by a qualified service technician!)
The DPA 4120 and DPA 4140 amplifiers allow the connection of 50V, 70V, 100V or low-impedance loudspeaker systems (4 ohms). They are factory-preset to an output voltage of 100 V. Switching the output voltage to 4 ohms, 50V or 70V can be performed by changing the bridge B411 on the power amplifier printed board assembly 84187 (DPA 4120) or 84175 (DPA 4140):
Caution Before opening the appliance, make sure to disconnect the mains and/or battery power source!
-To open the appliance, the top panel has to be removed.
-The bridge B411 (yellow wire) has to be removed from the contact B407 and re-attached to the desired contact (see table 1) (see also figure 8 respectively figure 9).
-he coding-bridges S405 and S406 for the output recognition have to be inserted according to the illustration in figure 5.
(the inserted coding-bridge is marked in black)
-The top panel has to be re-attached.
Note | By using a waterproof marker pen and after switching the output voltage, the newly set value |
| has to be marked in the filed "OUTPUT VOLTAGE" on the rear panel of the appliance. |
| |
output | bridge |
| B411 to |
100 V | B407 |
70 V | B408 |
50 V | B409 |
4 ohms | B410 |