Using or buying "vintage" stereo amplifiers

Lately I have seen a great deal of Facebook and Instagram posts with pictures of new speakers with 10+ year old amplifiers and receivers. Although these “retro” systems look pretty cool they could cause your speakers a world of hurt! At the heart of all amplifiers are extremely important components called capacitors. You can think of capacitors as storage batteries. When you plug into a wall outlet you are using AC (Alternating Current). Unfortunately AC power cannot be “stored” to be used later, so inside the amplifier this AC power is converted to DC (Direct Current) which can be stored in a battery type device like a capacitor! This stored power is then converted back to AC power to operate the speakers. Vintage capacitors generally were made 3 different ways, paper layer, polystyrene and metal film, with most electronics manufacturers using the lower priced paper layer or polystyrene type. Very few used the very expensive, and super long lasting metal film types, which have extreme longevity and work as specified right out of the box. Paper and polystyrene capacitor performance operate on what is called a performance bell curve. Brand new capacitors don’t store to spec, but after about 5 years the capacitors reach their designed storage and after 10 or so years they loose the ability to store power! When this condition occurs your speakers will not be getting their power from the capacitors, but directly from the voltage invertor, which can kill your speakers faster than you can turn down the volume! Tweeters will be the first to go, but there can be damage internally to the crossover. If you have this vintage amp/new speakers scenario keep the volume down and start saving for a new amp! Old amps and receivers should not be purchased on eBay or Kijiji (with very few exceptions… Macintosh, Krell, Conrad Johnson etc.) They should be taken to your local electronics recycling center.

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