Octave HP 300 MK2, Руководство пользователя

Страница: 21 / 25

23
11. TROUBLESHOOTING

Hum and crackling
Hum in an audio system is often caused by several system components being earthed
individually. It is particularly common with tuners, VCRs or satellite receivers, where the earthed
aerial cables cause a hum loop via the aerial input. Power amplifiers are normally also earthed.
Removing the earth wire on your mains plugs is not a solution. You can isolate the aerial earth
connection with a special signal isolator. This device has no adverse affect on the sound or
picture quality of tuners or TVs.
The HP 300 MK2 is not earthed and cannot therefore cause ground loops.

Clicks and pops
Older fridges and 12 V halogen lamps can cause cracking through the loudspeakers when they
switch on and off.
Solution: the only solution is to use a single power socket board for your entire system and to
use a different power outlet in your listening room.

Channels are not balanced
Check that the cinch plugs are a tight fit. Bend the outer earth contact inwards slightly if
necessary. Sometimes the internal pin in a cinch plug may not be a tight enough fit, in which
case you should change either the interconnect or the socket.
1. Damaged cables and poorly fitting cinch plugs can create resistance in the signal path,
enough to reduce the output level of one channel.
Solution: Try new cables or clean plugs and sockets with isopropyl alcohol. You could also
try cleaning or contact fluid.
2. A faulty tube can cause a drop in output in one channel and generate distortion. Although a
rare occurrence, the heater inside the particular tube may be the cause of the problem.
Solution: Replace the tube.

Increased hiss on one channel
Hiss that varies in level is a sign of a faulty or worn driver tube.
Solution: Replace the worn tube.