A question for grounding on the PASS DIY B1 Buffer . I can't seem to find the original B1 preamp-less version build guide onlineI used back when I bought the PCB and matched JFETS from the PASS store.
Power is from the recommended 18 volt .33 A SMPS and both input and output wire are braided solid copper bell wire . PCB is mounted on plastic standoffs to a metal Hammond Enclosure . Input Output jacks are isolated from the chassis and tied to the pcb ground .
If I introduce the B1 between source and amplifier it hums every time I touch the metal selector toggle switch or
the potentiometer and the DACT hums at the very last volume increment particularly.
Turning the amplifier all the way up I can hear a faint radio show .
I'm going to change the braided signal wire to shielded MOGAMI cable but wondered if I need to change the PCB to metal standoffs or ground the board to the chassis in some way ?
Has anyone else had a hum or ground issue with their B1 ?
Power is from the recommended 18 volt .33 A SMPS and both input and output wire are braided solid copper bell wire . PCB is mounted on plastic standoffs to a metal Hammond Enclosure . Input Output jacks are isolated from the chassis and tied to the pcb ground .
If I introduce the B1 between source and amplifier it hums every time I touch the metal selector toggle switch or
the potentiometer and the DACT hums at the very last volume increment particularly.
Turning the amplifier all the way up I can hear a faint radio show .
I'm going to change the braided signal wire to shielded MOGAMI cable but wondered if I need to change the PCB to metal standoffs or ground the board to the chassis in some way ?
Has anyone else had a hum or ground issue with their B1 ?
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This comment on the pass forum diy build guide post #1 might mean the B1 Build guide has changed after I first built the B1 buffer back during the Christmas holidays in 2016 ?
The build guide I used might have even been on the Audio Circles or Audio Karma sites since it's been a while , although I couldn't find it on searches.
Today I will wrap a ferrite core around the power cord just to see if it helps with the RF noise .
Thank you for suggesting on taking a ground from 10R NTS on the board .
I don't see a Resistor marked R10 on the Schematic though
.... and maybe someone could let me know what the NTS acronym stands for ?Thanks
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