How long do 12AU7 tubes last?
between 5,000 and 10,000 hours
Tube Life. Small signal tubes like 12AX7 and 12AU7 typically last between 5,000 and 10,000 hours. You don’t need a tube tester to determine if your tubes need replacing. Simply plug in a new pair and let them settle in for at least 100 hours.
How can you tell how old a tube is?
The second character indicates the year of manufacture. For the date code shown in the picture, the ‘9’ indicates either 1969 or 1979 depending on the change code….The third character indicates the month of manufacture:
- A – January.
- B – February.
- C – March.
- D – April.
- E – May.
- F – June.
- G – July.
- H – August.
What is the difference between 12AX7 and 12AU7?
The biggest difference between these power tubes is the amount of gain they will provide. The 12AX7 has a gain factor of 100, while the 12AT7 has 60. The 12AU7 has the smallest, at just 20. The lower gain of the 12AT7 and 12AU7 also allows them to have a higher headroom, which can provide a warmer and cleaner sound.
Can I replace 12AX7 with 12AU7?
You can interchange a 12AX7 with 12AT7, 12AU7, 12AY7 or 5751 as they are all the same pin structure, however they will each give you a different result in your amp. Each of these tubes has a different gain factor, which means some will give higher gain and others lower gain.
How long do tubes last in years?
Tube Life Span Preamp Tubes are generally at their best 2 – 3 years. Power Tubes are generally at their best 1 – 1.5 years. Rectifier Tubes are generally at their best 3 – 5+ years.
Are old electronic tubes worth anything?
Some older Western Electric tubes unused or the original box will sometimes sell for over a thousand dollars at auction. Western Electric “Tennis Ball” tubes have glass globes about the size and shape of a tennis ball with a glass tip on the top. These numbers include 101D ($400+) and 205D ($300+).
Do preamp tubes go bad?
Preamp tubes can go bad at any time and for any reason. There is normally no way to determine how long they will last. Sometimes the heater inside can fail and will no longer glow. This will prevent it from working completely.
How long do tubes last in a preamp?
2 – 3 years
Preamp Tubes are generally at their best 2 – 3 years. Power Tubes are generally at their best 1 – 1.5 years. Rectifier Tubes are generally at their best 3 – 5+ years.
How long does a tube last?
Tubes don’t just “quit” suddenly. They lose their drive capability gradually with use. Small signal tubes like a 12AX7 or 6922 will work well on average for about 10,000 hours. If you leave your equipment on 24 hours a day, well you do the math: There are 8,760 hours in a year.
How do you check tubes?
Turn on the machine to activate the tubes, and look for an orange, red, or purple glow. If the heated filament inside the tube glows orange like a setting sun, it’s usually a sign that the tube is healthy. The filament may be hard to see. If you don’t see the glow, that doesn’t necessarily mean the tube is bad.
When should I replace my tubes?
A: These are the most common signs that tubes need replacement:
- Excessive noise (hiss, hum) including squealing or microphonic tubes.
- Loss of high end.
- A muddy bottom end; Sounds like there is too much bass and note clarity is lost.
- Erratic changes in the overall volume.
- The amp doesn’t work!
How much are electron tubes worth?
How often do tubes need to be replaced?
On average, tubes can last from 500 to 1,000 hours, so if you play with your amp two to three hours every day, you can safely expect to get around a year or less from your vacuum tubes.