Q: Is Biasing covered under warranty?
A: Typically not. It should be considered as part of the routine maintenance in keeping your amplifier at its peak performance. However, if re-biasing is required as part of other warranty service, it will be covered under the warranty policy.
Q: My tubes are not working (i.e. not lighting up, no output, etc).
A: Check the following:
Make sure the tube is firmly seated in the tube socket
Other tube situations:
My tubes make a popping sound accompanied by intermittent light from tubes - the tube is failing and needs to be replaced.
The appearance of â€œwhite frostâ€ inside the tube â€“ the tube has cracked and it must be replaced.
General Guideline for Replacing TubesÂ· Always replace power amp tubes with matched set(s) every 12-24 months depending on the amount of use, and have the bias checked and/ or adjusted by an Authorized Line 6 Service Center.
Preamp tubes (such as the two 12AX7s) only need to be replaced when they are microphonic (ringing sound from tubes when tapped), noisy, or damaged.