2019年1月14日 · In an EL34, pin 1 connects to grid 3, while in a KT88, grid 3 connect to the cathode directly. Thus, having pin1 connected in the SimpleSE allows for EL34 valves to be used.

2023年6月29日 · A new power transformer would allow the KT77, KT88, and EL34 to be used. Do not forget to wire pin 1 to pin 8 for the EL34. And be sure to check that pin 1 on the KT88 does not connect to the metal shield that is just above the octal header of the tube (a connection there would put the self bias voltage on that shield).

The KT88 is a beam tetrode /kinkless tetrode (hence "KT") vacuum tube for audio amplification. Radio Tube Data, Eighth Ed. Ilife Books Ltd., London, 1966. The KT88 fits a standard eight-pin octal socket and has similar pinout and applications as the 6L6 and EL34.

2020年11月25日 · If I want to replace the current KT88 tubes in my amp with EL34 (to compare sound) I need to make a connection between pins 1 and 8 of the tube sockets and properly adjust bias.

2020年7月3日 · KT88 and 6550 are essentially interchangeable, so either would work. Pin 1 may or may not be connected to the base shell, so check that. Another option would be to use EL34's, and miss-match the speaker load to double the primary impedance. I don't know what the Zpri is, but I'd guess 4k8.

2021年9月5日 · 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. The device has an anode dissipation of 35W and is primarily designed for the output stage of an a.f. amplifer for which two valves will provide up to 100W output.

Two valves in Class ABI give a continuous output of up to IOOW. The KT88 is also suitable for use as a series valve in a stabilised power supply. The K T 88 is a commercial version of the C V 5220 and is similar to the 6550.

The KT88 has an absolute maximum anode dissipation rating of 42W and is designed for use in the output stage of an a.f. amplifier. Two valves in Class AB1 give a continuous output of up to 100W. The KT88 is also suitable for use as a series valve in a stabilized power supply.

It's kind of hard to understand why a resistor would be placed from pin 1 to pin 8 on a KT88. Usually pin 1 and pin 8 are shorted together, and then 560 ohms might be the cathode load resistor to ground.

2019年1月6日 · While powered up in the test described in #3, measure voltage on pin 5 of both KT88 sockets (no KT88s in the sockets). You should measure zero volts and if so, that tells you the output stage coupling caps are not leaking.