After replacing a tube, with the volume
mid-way, I can hear my hand touching the
preamplifier through the loudspeakers, like
an echo.
After de-selecting an input I can still hear
it in the background.
Maintenance 7 - 4
Troubleshooting
1
. The tube you have replaced is ' microphonic '.
This is particularly noticeable if the tube has been
fitted in the phono stage.
2.
Change the tube for another.
1
. This is caused by breakthrough on the selector
switch, it cannot be avoided, unless complicated
sound degrading circuitry is employed. The best
advice is to switch of the offending signal, this is
particularly true for tuners which are often left on.
SYMPTOM
REMEDY
UNDER NO CIRCUMSTANCES SHOULD AN UNQUALIFIED PERSON REMOVE THE
COVERS OF AN AMPLIFIER. IF IN DOUBT PLEASE CONSULT YOUR DEALER OR
TUBE TECHNOLOGY.
