KT90 Triode mode Push Pull Integrated Tube Amplifier + NOS 6N1P-EB + EH12AT7WC

  

For sale is a Triode Push Pull Integrated tube amplifier. This unit was mounted on a used stainless steel chassis of a Music Angel tube amplifier. The PCB with input and driver stage was partial modified and upgraded with new parts. Power Output: 30W per channel. Line inputs : 3 x RCA.

Type of Chassis : Stainless steel with wood side frames. Tube sockets : All tube sockets are ceramic with gold plated pins. Tubes :The amplifier will be supplied with a new set of tubes: 4 x NOS Ei KT90 matched + 2x NOS 6N1P-EB on the driver stage and 2x EH 12AT7WC on input stage.

The power tubes are connected only in triode mode. Can be used with other power tubes such as: EL156, KT88, 6550, KT120 without the need for any modification or bias adjustment. The original Telefunken EL156 can be used but with socket adapters, not included.

Driver tubes: Can be used without any modification other driver tubes such as 6FQ7, 6SN7 (only with tube adapters, not included). The driver stage also support ECC82/12AU7 tubes, but only if 12V for the heaters is selected on the switch inside the amp (check the pictures).

Input tubes: Instead of ECC81/12AT7 can be used the ECC85, if selected 6V for the heaters of input tubes on the switch inside the amp (check the pictures). For adjust and control the Bias of Power tubes was used a TentLabs Negative Bias Supply module, which garantees under all conditions a constant plate current for the power tubes, to achive optimal performance of the amplifier. This module also ensures smoth start for power tubes and features a Low Bias mode that reduces the bias of Power tubes by half the current set when amplifer is used in non-critical listening to extend the life of power tubes. More information about this module can be found at the following link. The module was been adjusted to 60mA plate current, but can be adjusted to other plate current values if desired.

CLC on high voltage filter stage. The filter capacitors are Mundorf MLytic. For the driver and input stages was used a aditional filter stage separated for each channel with a Tentlabs electronic filters MEC50. The Amplifier is completely silent even when connected to high efficiency speakers.

For the HT bridge diodes was used FRED diodes. The power transformer was custom made for this unit. For signal coupling capacitors was used NOS Paper in Oil capacitors (the red ones on the picture of interior) made for audio, between driver stage and power tubes and Vishay PP capacitors between input stage and driver tubes. Volume potenciometer is a Alps RK27 Blue.

Input selector is a high quality unit with silver contacts. Input signal cables are silver plated shielded wire.

The amplifiers are configured only for 230VAC. Please ask if you need more pictures or details. For any further questions please contact me.