Guitar Amplifier Servicing
Guitar amplifiers require a different type of service when compared to hifi pieces. They are subjected to the stresses of gigging and touring, and need to be well maintained so that they are extremely reliable.
When it comes to a general servicing, such as replacement of power tubes, the entire amp is looked over to make sure that there are no loose controls or inputs that could cause problems. Internal components are given an inspection, and recommendations are made if something should be replaced.
Typical amplifier servicing:
- Replacement of tubes & biasing when required for power tubes
- Cleaning of controls
- Checking and tightening nuts, bolts, jacks, etc.
- Preventative maintenance (replacing 20+ year old electrolytic capacitors)
- Thorough testing to make sure everything is functioning properly
We can service many brands of guitar amplifiers, including (but not limited to):
- Bad Cat
Attention to Detail
An example of the special care required with guitar amplifiers is during the recap of older Fender amplifiers. In Silver or Brown face amplifiers the main filter capacitors are found in the “dog house.” This part of the circuit sits atop the chassis next to the tubes and transformers under a metal cover. When the amplifier is fully assembled the capacitors hang upside-down. Whereas when recapping a hifi amplifier you would not worry much about it, guitar amplifiers (especially combos) are subject to high levels of vibration. Relying on just the leads of the capacitor for support can be asking for trouble. With enough vibration the leads will work harden and break off – leaving you stranded at your gig with a loud humming amp. To mitigate this, a thin bead of high-temperature RTV silicone is added to the body of the capacitor before installation so that the body is adhered to the eyelet board – reducing the lead stress significantly. This technique is is used in all guitar amplifiers and other pieces of equipment that subject components to physical stress.