Certon M21 User’s Manual
7
There are no user-serviceable parts inside the enclosure. Opening the cover
exposes high-voltage surfaces that may cause electric shock.
Your Certon M21 has a DC protection circuit through which DC faults are detected. In the
event of a malfunction within the unit, or in another component of your audio system that
leads to a DC offset, the M21 shuts down. A LED indicator (11) indicates that a DC fault has
occurred. This may be a single event or a persistent condition. Try to reset the amplifier by
turning it off, and then back on. If the problem persists, try a different pre-amplifier (or
completely turn off the pre-amplifier) and reset the M21 once more. If this does not rectify the
problem, your M21 may require servicing by a qualified technician.
Do not repeatedly reset the M21 without taking consecutive action to try to
resolve the problem with DC offset, as this may subject the amplifier to unnecessary
stress. In the event of loud thumps, clicks or pops from the loudspeaker at reset, do
not proceed but seek assistance from a qualified technician.
There is a heat switch inside the enclosure. The heat switch protects the amplifier against
excessive and potentially harmful temperatures that may result e.g. from loud listening for
prolonged periods at elevated ambience temperatures. When the heat switch trips, the
amplifier turns off. As soon as the temperature is safe again, the amplifier is ready to be
turned on again.
Specification
Power (8 Ohms)
25 Watts RMS
Damping factor (8 Ohm)
>450 @ 100 Hz
Input impedance (RCA/XLR)
40 kOhm/80 kOhm
Input voltage (at full power) (RCA/XLR)
1 Volt RMS/0.5 Volt RMS
THD+N
< - 60 dB
Output binding posts
WBT
Audio input jack
RCA phono type (cinch) and XLR
Remote trigger voltage
12 VDC (either polarity)
Remote trigger connector
3.5 mm. tele jack (mono)
Enclosure
Steel
Weight
2.8 kg (6.2 lb)
Size of enclosure: (width x depth x height)
205 x 200 x 120 mm. (8.1 x 7.9 x 4.7 in.)
Mains voltage
AC 110 - 230 Volts, 50 – 60 Hz
