ac ground loop

maxpou

Member
2006-04-02 7:17 pm
Québec
Hi Guys
I have a possible ac ground loop with my simplistic riaa phono stage. In another thread i had a AC ground loop with my mono power amps and my preamp. I resolved my problem when I read the groung loop document of Bonsai. I put a hum breaking resistor in my power amp. Now i has a new ground loop problem when i connect my phono stage, i tried a ground lifter in my preamp without success. If I connect my phono stage with my turntable on my old Onkyo receiver and this one has no earth ground I don't have hum noise:confused:. Somebody can help me?

thank you! Maxpou:)

p.s.: my turntable is a thorens td125 modified without ground wire.
 

maxpou

Member
2006-04-02 7:17 pm
Québec
hi guys,
sorry for delay and thank you for reply guys. I have worked on my problem last week and I resolved it when I put a ground loop breaker in my amp with a 25A bridge and 0.1 uf cap between the gnds like in the page 56 in this doc. http://hifisonix.com/wordpress/wp-content/uploads/2019/02/Ground-Loops.pdf. Now for my preamp and phono preamp I putted the safety ground on my chassis only and my audio ground is floating, should i put a ground loop breaker in all my device or not? thank you! Maxpou