Parallel Mode; Cleaning And Maintenance - Velleman VPA2450MB Manual Del Usuario

c. Balanced / Unbalanced Input Connection
If an unbalanced input signal is to be connected using an XLR plug, a wire bridge must be
inserted between PIN1 and PIN3 (see figure on the left). For an unbalanced signal input, a
6.35mm mono jack plug can also be used.
d. Mono / Bridge Mode
In MONO mode, only the channel A input is active. The selection switch (#13) must be set to the BRIDGE position.
In BRIDGE mode, both amplifier channels (A & B) are internally bridged to perform as one single channel. Only the
channel A input is active. In both modes, only the BRIDGE output connector (#9) may be used.
The channel A and B connectors (#8 & 10) are only for use in STEREO mode
(selection switch #13 in STEREO position). The connection must be made as in the
figure on the right, using a professional connector (type CAS101):
Minimum speaker impedance for mono or bridged mode is 8 .
e. Stereo Mode
In STEREO mode, connect channels A and B through the XLR or phone jack plugs. The selector switch (#13) must
be set to STEREO. Use the channel A & B output connectors (#8 & 10). Minimum impedance is 4 /channel.
f. Parallel Mode
Mono or bridge mode will mostly only allow driving one single loudspeaker system due to the 8 min. impedance.
If, for example, a number of floor monitors (8 each) are to be driven, channels A and B should be in parallel mode:
- connect the input signal to the channel A XLR input
- connect the channel A and B phone jack inputs by means of a shielded patch cable.
- set the selector switch (#13) to STEREO
- connect the speakers (minimum impedance 4 ) through connectors A and B (#8 & 10).

6. Cleaning and Maintenance

1. All screws should be tightened and free of corrosion.
2. The housing and fixations should not be deformed, modified or tampered with.
3. The electric power supply cables must not show any damage. Have a qualified technician maintain the device.
4. Disconnect the device from the mains prior to maintenance activities.
5. Wipe the device regularly with a moist, lint-free cloth. Do not use alcohol or solvents.
6. There are no user-serviceable parts except for the fuse (see "4. Fuse Replacement" on p.1).
7. Contact your dealer for spare parts if necessary.
VPA2450MB / VPA2620MB / VPA2700MB
Both amplifier channels feature a balanced XLR female socket as well as a balanced
6.35mm phone jack socket.
Input cables must be screened!
3 VELLEMAN