Ruby KT88STR Power Vacuum Tube
Ruby KT88STR Power Vacuum Tube
Ruby KT88STR Power Vacuum Tube
Ruby KT88STR Power Vacuum Tube
Ruby KT88STR Power Vacuum Tube

RUBY Tubes

Ruby KT88STR Power Vacuum Tube

$50.00
In stock
Matched Set:Single
Quantity:

Upgrade your sound experience with the RUBY KT88 Power Vacuum Tube. This high-quality tube utilizes RUBYS advanced technology to deliver superior audio performance. With a sleek design and reliable construction, this vacuum tube will provide long-lasting durability and enhance your music with clear and powerful sound.


The KT88 is a beam output pentode with an octal base and power of 42W. Very powerful, with strong bass and very bright highs. It can also be used in 6550 amplifiers.


All RUBY™ Tube power tubes come already matched. There is no extra charge for this service. Our Magic Parts matching process is very exact and our tubes are matched within +/- 1 mA (mille amp) of each other.

6 Month Warranty On All Tubes

Matched Sets

Each tube is individually tested, measured, and precisely matched to the same milliamp to ensure consistent electrical performance across every set. This careful matching process promotes balanced operation, reliable response, and long-term stability in your amplifier. Precision milliamp matching is a standard part of our quality control and is included at no additional cost.

Matched Sets

Each tube is individually tested, measured, and precisely matched to the same milliamp to ensure consistent electrical performance across every set. This careful matching process promotes balanced operation, reliable response, and long-term stability in your amplifier. Precision milliamp matching is a standard part of our quality control and is included at no additional cost.

Carefully Tested

Every tube is subjected to a comprehensive testing process using custom-designed, calibrated equipment to evaluate key electrical and performance characteristics. Each tube is measured for proper operation, stability, and consistency before it is approved for sale. This thorough testing ensures that only tubes meeting our strict performance standards are shipped, providing dependable operation and long service life.

Carefully Tested

Every tube is subjected to a comprehensive testing process using custom-designed, calibrated equipment to evaluate key electrical and performance characteristics. Each tube is measured for proper operation, stability, and consistency before it is approved for sale. This thorough testing ensures that only tubes meeting our strict performance standards are shipped, providing dependable operation and long service life.

Burned in

Every tube is subjected to a controlled burn-in process at no additional cost prior to shipment. During burn-in, tubes are operated under load for an extended period to identify early failures and ensure stable, reliable performance. This process helps eliminate weak or unstable tubes before they ever reach your amplifier.

Burned in

Every tube is subjected to a controlled burn-in process at no additional cost prior to shipment. During burn-in, tubes are operated under load for an extended period to identify early failures and ensure stable, reliable performance. This process helps eliminate weak or unstable tubes before they ever reach your amplifier.

All our tubes are matched. for free.

No Extra Cost.

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