so many of us, our first projects revolved around audio electronics, and majority of which was building mic preamps and amplifiers.
One of our biggest problems was that dreadful hum that's present when we hit our preamps just above 12'oclock.
now I'm not an audio engineer, nor do I have a degree in electronics..but my dad has... But I'm a hobbyist needless to say.. anyway this post is more of a tips and tricks and knowing to how to have a workaround to eliminate those nasty hums..
PREAMP HUM PROBLEMS
now if you built your own preamp, chances are you connected all the common ground together before it entered the preamp. Now this is very common human error said my dad. This happened to me when I built my first phono preamp, my preamp was just humming crazy when I first built it. so here are some few tips on how to fix it.
TIP 1 :
in any audio project, NEVER connect the grounds to one another, and make sure it's not connected to the chassis either. what I'm trying to say is, the RCA's ground should not be connected to one another. both the input and output.
TIP 2 :
the wires that you are using! in audio projects, it is preferred that you use shielded wires. this also made a huge difference in my preamp.
TIP 3 :
the 0v or GND in your power supply.. yes guys, we need to hook it up to our chassis.. and I recommend building your power supply externally because if you don't shield your transformer, chances are your project will still hum.
TIP 4 :
WRAP if your enclosure is made of wood or plastic, wrap it with aluminum tape. do it also in your power supply enclosure if its not metal.
for now this are my tips, I'll keep updating this whenever I experience hums in my future projects. so for now, if you have suggestions to solve those pesky hums and ground loops, just leave it in the comments section below.