We all like to swap out equipment, but handling your equipment the right way is imperative for both maintaining it and your resale value. Some audiophiles may take a break from listening or may just change out their equipment every so often, leaving some electronics stored away for a period of time. It is important to understand how to warm up and restart that equipment when you get it back out without damaging it or harming yourself.
Audiogon user Elizabeth came up with this DIY variac approach. She said, “The caps need to be babied, and the momentary turn on, then longer do the same job, only for free. Have some load on the amp if you do my method. For a tube amp always have a load (speakers) on it if it is turned on. For solid state amp or preamp, this is not necessary. For a tube preamp, it is also a good idea to have the outputs connected, thought not nearly as important as a tube amp. Yes, my method is the cheap way to do it. It works, and accomplishes the same thing as using a variac (forming the capacitors).”
Here is a do-it-yourself method of gently restarting a tube amp and pre from storage.
1. Bring the amps to room temperature of 72 degrees for at least a day.
2. Plug them in and turn them on for only a moment – fast on and off for less than a second.
3. Wait 20 minutes or so.
4. Flip them on again for about three seconds, then off again.
5. Wait an hour.
6. Turn them on for 30 seconds, then off again.
7. Wait a few hours.
8. Enjoy!
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Hmmmm….I really believe in the variac method, but if you don’t have one, you can come up with an alternative, in a pinch. Cut an extension cord and put a 40 watt to 100 watt light bulb in series with the positive wire. Let the gear pull current across the bulb for 2-4 hours and then it should be OK to hook it up directly to the mains. Voila, and a much more gentle method. Going direct to the mains may be fine with modern gear that has been sitting for a while, but is not recommended for vintage gear that may have been sitting for a decade, or more.