On this page we have shown a few of the most frequently asked questions about our service and the equipment that we work on. We have kept the answers short and tried to use plain everyday language.
Question: What is a Valve Amp Health Check …..
Answer: A “Valve Amp Health Check” is a like an MOT for your Guitar amplifier.
Question: Why would I need a Valve Amp Health Check …..
Answer: Because valves age whenever they are switched on, they have a limited life. The tone that is produced will vary over the life of a valve and will gradually move away from its optimum performance. The valve may still work but it will not produce the desired tone or volume – Our “Valve Amp Health Check” will give you a diagnostic report as to the condition of each valve and how well it is matched to its output companion.
Question: What is meant by the term Biasing …..
Answer: On some amplifiers you can adjust the point (the bias point) that a valve sits at when the amplifier is turned on and waiting for a signal from the pickups on your guitar (ie) you are all set to go but not yet playing. The correct bias point is important as its sets up the valve’s ability to give you the best tone and volume for your amplifier. The bias point can drift away from from its original setting due to factors such as valve usage and component aging – This is one of the main settings to be checked during a service or when new valves are fitted.
Question: What does the Standby Switch do …..
Answer: The standby switch is a device of myth and mystery for many players and sadly to say the occasional technician. Some amplifiers have them fitted and some don’t, by general consensus it is said that the trend was started by Fender and copied by Marshall.
All of that said you can think of the standby switch as a “Master Mute Switch” as it turns off the supply voltage (HT) to the valves but generally leaves the valve heater circuit working. This has the effect of keeping your amp warmed up between sets and instantly ready to play. It can also be used to stop your speaker popping if you need to swop guitars mid set. If the amp is turned to standby before it is switched off you run the risk of leaving the high voltage components in the power supply fully charged which can reduce their lifespan and could present a shock hazard.
This is my guide to using a “Standby Switch” …
1. Make sure the “Mains Switch” and “Standby Switch” are in the off position then plug in the guitar and the mains lead.
2. Switch on the “Main Switch” and then after one or two minute’s turn the “Standby Switch” to the playing position – The time delay between operating the two switches allows the amplifier output to warm up and stabilize.
3. Play to your hearts content !!!!
4. Switch the amplifier to “Standby” between sets – This will “Mute” the amplifier without having to change any settings.
5. When done, switch the “Mains Switch” off with the “Standby Switch” in the playing position and strum the guitar until there is no sound from the speaker – This ensures that the power supply components are fully drained before you pack the amp away.