gofar99 Messages: 1949 Registered: May 2010 Location: Southern Arizona
Illuminati (5th Degree)
Hi Everyone. BTW...I changed the name. (harmony one) I attached a schematic with mark ups. Some components are numbered so you can relate to the photos. Red arrows are pointing to changes. The large circle in the middle is the main ground point. Everything goes to it. The "H" shaped buss only carries signal grounds. Power ones in that area go back to the power supply. The power supply has only one connection to the ground at the central point. This is a bit of deviation from many of my builds as they usually have the central ground at the input jack ground. In this build The shield of the input jacks is only attached at the jack end and a separate wire goes to the main ground. The X2 capacitor goes from the power supply ground to the AC mains ground. It could go to the main ground and I may move it later.
As the photos show I used mostly budget audio grade poly caps for power supply filtering. The single 100uf electrolytic was necessary to get the hum down enough. I tried several other locations and various filter configurations and this worked best. The final stage is a FET capacitor multiplier. It worked best as the last filter. The heaters are raised above ground to protect the tubes.
In retrospect I would use a larger transformer when using the 6AS7s. The one specified is running at near capacity and when inside the steel case gets pretty warm. With 6SN7s it is fine.
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