Hum in one speaker?


Hi, ive been having this hum thats been comming out of my right magnapan speaker. Well first thing is that my whole system is on the right side of the room and the speaker is right next to the equipment but its been like this for years and I never had a hum before. This seems to happen when using the turntable but only with certain albums that have been recorded at a low levels causing me to turn up the pre amp past 12o clock. Recently I put my speakers on mye stands with magic sliders and I dont know if that may have caused an issue or mabey its a bad vaccume tube? I tried moving the speaker around the room didnt seem to do much but the hum seems at its worst at the best listening spot (go figure). Mabey its my cartridge? I dont know but right now my turntable is about 30 inches away from the speaker. The hum is not horrible but when the music gets quiet it can be annoying. I did swap the speakers and with the tweeters on the outside the hum seems to be worse not better.
barruch86

Sometimes cables fresh from the factory are the worst for schmutz. There can be like this oil stuff on the connector, that is a residue from the manufacturing process.

And what is worst is when you have the oil get from the jack into the socket, because it is harder to clean then. The way to clean that out is to first clean the jack with alcohol, then plug the jack in, jack it in and out, and then clean the jack again. Repeat until you get a solid connection every time you plug in. Your using the clean jack to wipe out the socket.

A totally different topic... if you crank an amp up and the hum gets relatively louder than the music, it can be a sign of having an electrolytic power cap in the power supply going bad. What happens is that the cap is weak, and at high current draw of the amp, the weakness shows up as being significant, but at low volume the cap is able to keep up with the current demand. What was a hefty 4700 uF cap has degraded to a 500 uF cap, and it is not able to smooth out the 60 Hz ripple of the AC power supply when load current demand gets high. There isn't much you can do about a problem like that, the cap will progressively degrade over months or years, and eventually fail altogether. The cap has to be replaced.

If the hum is coming in through the signal path, the relative volume of hum to music volume will remain the same as you crank up the amp.
Oh wow i never thought that it could possibly be a cap issue, i dont think it is, but it might be . My power amp is an audio research vs110 that is about 10 years old now and pre amp well is probably 28 years old lol. I bought them both used, but the sp8 does have nichicon elecrolytics and im not shure if they are original or not. I think they used spragues back then but I could be wrong. The question I have is if its an electrolytic cap getting weak, then wouldn't both of the speakers hum instead of one? The hum did dissapear for now, but if it comes back then yea your right it might be a cap!
Its def the right interconnect cable on the turntable because again today the right side was out again with just a hum. I touched the right interconnect cable connected to the turntable and the sound came back on with no hum! I havent cleaned the system yet so ill clean the schmutz on the turntables connectors first and tighten the ground screw as that could have been a bit tighter. I hope this was the issue and not a cap because that sounds like id have to send them to a repair shop and I dont know how much that would cost lol.

I think your problem is schmutz and not a cap. I mentioned the common cap problem because the symptoms are similar. I wanted other people who are reading this to know how to tell power supply hum from pickup hum.

When the noise is coming from pickup in the signal path, the signal to noise ration remains the same, because you are faithfully amplifying both of them. When the hum is a droopy cap in the amp power supply, the signal to noise ration will be worse when you crank it up. It might even start "motor boating". Also, a power supply cap that is on it's way out gives off an acidic smell, like lemons.