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    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Improvements in this riaa tube

The buzz could be because of the way the chassis/box is connected to ground ... how you did it ?


Hello, the GNDs are all centralized in the same point located in the RCA connectors and these ground comes from the preamps through the house- gnd that I have attached.
 

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I have been thinking that instead of using step - up transformer ?.
Is it feasible to use a 2SK170 for gain as in the schematic I have attached? I only use cartridge MC
 

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  • 6C45riaa modificado.jpg
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The connection is fine.

The Ia of 6C45 is 8 mA
The Vk is around 5 volt

Have you done some measurement on gain and Thd?

The impedance of the output stage is not so low also for a non bypass on 5751.
The output cap is also too low in case a standard input line stage.
Which is the Z in of the line stage?

Walter
 
Last edited:
The connection is fine.

The Ia of 6C45 is 8 mA
The Vk is around 5 volt

Have you done some measurement on gain and Thd? I have no means to measure THD

The impedance of the output stage is not so low also for a non bypass on 5751.
The output cap is also too low in case a standard input line stage.
Which is the Z in of the line stage? Around 12K

Walter