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Important Things You Should Know Before Selecting a Tube Amplifier

Do you find yourself listening to music and feel like something is missing? A tube amplifier could be the missing piece because it makes your music come alive with realistic vocals and instruments with an overall full range of sound and can bring a new definition of music to your ears. A wide selection of valuable vacuum tube amplifiers can be found on eBay.

What type of vacuum tube amplifiers are available on eBay?

The wide selection of vacuum tube amplifiers on eBay includes new and used models, a kit assembly, and preamplifiers. Other types include single-ended triode(SET), push-pull, triode, pentode, ultralinear, and class A. These amplifiers also offer many features such as Bluetooth, active amplification, remote, Vu meter, and multiroom capability. Many of these amplifiers are also portable.

  • SET: These have lower power on average but are very common among tube enthusiasts. A single output tube controls both the positive and negative waveforms, and they are similar to Class A types.
  • Push-Pull: This specific type has dual-output units. One handles positive and the other controls the negative wave outputs. They have more power compared to SET.
  • Triode: The simplest design, this consists of a cathode, grid, and plate for amplification.
  • Pentode: This has five elements and generally gives better control of the tube. It consists of three grids, a plate, and a cathode.
  • Ultralinear: This is similar to a push-pull design that aims to minimize specific types of distortion.
Do amplifier vacuum tubes have to be matched?

Vacuum power tubes should be matched electrically for optimal sound quality and longevity of the amplifier. This is achieved by ensuring each plate has equal idle current for the amplification process. The plate current is simply the current entering the plate before amplification.

How long do vacuum tubes last?

On average, vacuum tubes will last between 500-1000 hours. This will vary depending on the type and manufacturer.

  • Rectifier tubes: These are designated for the power supply and convert alternating current(AC) to direct current(DC).
  • Preamp tubes: Typically, they are small and add gain or increase the input signal before amplification.
  • Output tubes: These are usually the largest and provide the current to drive the speakers. They tend to have the shortest lifespan because of the high current they produce.
  • Bias adjustment: This is required in most cases when an amplifier output tube is replaced.