Hi,
I am building a Rod Elliot ‘Hi-Fi with tone controls preamp’, project 97. The power supply will be inside the chassis along with the amp board and phono preamp board, and consist of a +/- 15V from a toroidal transformer + bridge rectifier and filter caps.
In addition to locating the transformer as far as I can from the inputs and amp board, should I insert a steel or aluminum separator , like I see in so many pictures of preamps?
Rob
I am building a Rod Elliot ‘Hi-Fi with tone controls preamp’, project 97. The power supply will be inside the chassis along with the amp board and phono preamp board, and consist of a +/- 15V from a toroidal transformer + bridge rectifier and filter caps.
In addition to locating the transformer as far as I can from the inputs and amp board, should I insert a steel or aluminum separator , like I see in so many pictures of preamps?
Rob
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I would say it's unlikely you'll need any shielding of the transformer. Lay everything out the way you want and give it a listen. This is a good article that helped me. The headphone trick is especially helpful.
I built the project 97 preamp as well and I have no hum with the setup pictured. I mounted the board vertically and divorced the pots because this was a retrofit and the spacing was different than Rod's board. Despite the longer leads it's still silent. Read Rod's article on grounding and use a ground breaker. You are more likely to get hum from improper grounding than from the transformer. More good articles referenced here.
I built the project 97 preamp as well and I have no hum with the setup pictured. I mounted the board vertically and divorced the pots because this was a retrofit and the spacing was different than Rod's board. Despite the longer leads it's still silent. Read Rod's article on grounding and use a ground breaker. You are more likely to get hum from improper grounding than from the transformer. More good articles referenced here.
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I always do use a steel, case divider to isolate the power traffo from the PCB, with source components.
Thanks for the links to the articles. There's a lot of information there. I think I'll try it without a shield, and test for hum. If there's hum I'll troubleshoot and try a shield or something else. BTW, I think you posted the wrong pic. ;-)
It's hard to see but Rod's preamp is in the pic right behind the blue pots. Mounted vertically to an aluminum plate.