14
EvoLution Series
Troubleshooting Tips
No output. The power switch is on, but the power LED is off and tubes do not light up.
•
AC cable makes a bad connection in the IEC connector. Please check.
•
Mains fuse is broken. Please check.
•
PTP™ (Power Transformer Protection) protection may have switched off the power transformer.
If so, the amplifier will switch on again after the internal temperature of the power transformer
returns to normal. Overheating might be caused by higher environment temperature than normal
or heavy use.
No output. The power switch is on, the front LED is green and tubes do light up.
•
Adaptive Auto Bias Board fuse is broken. Please check.
No output. The power switch is on, the front LED is red and LED in front of a power tube MIGHT light up.
•
BTI
TM
circuit has switched off the high voltage supply to the power output tubes.
This can happen for example, when one (or more) output tube(s) draw(s) significantly more
current than normal, like what can happen when a loudspeaker terminal is short-circuited with the
volume turned up.
•
In case of an internal output tube failure, the BTI™ circuit understands that there is a new
situation which can cause harm to the amplifier or the loudspeaker, and the high voltage power
supply to the output tubes is interrupted as a protective measure. The front LED will turn red and
you might see a red LED in front of one or more power tubes. To reset, switch the amplifier’s
power off for at least two minutes, then switch back on. Of course, this should only be done after
the cause of the failure has been identified and resolved. Switching the power back on too early
can fool the BTI
TM
circuit into acting as though the problem has not been totally resolved and it
may put the amp back into protection mode again. So be sure to give it enough time to reset.
Noise or hum coming from one channel (eventually when you change your volume setting).
•
Noisy tube. At first swap the two inner small tubes left to right. If noise follows the tube swap then
you have found the problem tube. If noise does not follow, swap the next set of two small tubes
left to right, eventually the next set in case your amplifier has 6 small tubes.
•
Possible bad output tube. Swap the output tubes in pairs from right to left. If hum follows the
swap, swap the far left and far right tubes. If the hum returns to the original problem channel, you
have found the problem tube. If not, swap the inside output tubes left to right.
Noise/distortion coming from both channels.
•
Tubes may be in need of replacement.
