M THE DAILY INSIGHT
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Why does my phono preamp make a hum sound?

By Isabella Ramos

Why does my phono preamp make a hum sound?

A reversed wire here can easily cause hum. Make sure that your turntable and phono preamp are NOT locted close to major sources of AC fields: Power amplifiers (which have large trsansformers in them), AC cables, AC power “conditioner”, or other electronics. Make sure BOTH channels are making music.

Why does my turntable hum when I turn it on?

If hum only occurs on the input which the turntable plays through, it is logical that the turntable is the source of the problem. Some readers of this article may have a phono preamp as part of their system, which can also cause hum.

What do I need to make my phono Hum?

If there is a hum, powersupply service is probably indicated. This will require one accessory, a shorting plug. You need to get a couple of standard RCA plugs from Radio Shack for instance, and you need to short the center pin to the outside ground.

Why do I have a hum coming from my speakers?

It is also possible that the cable end is not soldered or connected properly to the RCA plug. Often, molded plugs (not serviceable) become faulty. Pushing on the wire as it enters the back of the plug may temporarily heal and reveal this kind of problem. If you DO have sound out of both channels, and you have hum, then……

A reversed wire here can easily cause hum. Make sure that your turntable and phono preamp are NOT locted close to major sources of AC fields: Power amplifiers (which have large trsansformers in them), AC cables, AC power “conditioner”, or other electronics. Make sure BOTH channels are making music.

What can I do about the Hum on my turntable?

You can further troubleshoot the cartridge wires by connecting the {blue and white} and {red and green} wires together using an alligator clip. This should eliminate the hum. If it does not, then the wires need replacing.

Modern signal cables are well shielded, but if you’re getting hum and it’s not a ground loop, this could well be the cause. Note that the cables running to self-powered speakers (non-Wi-Fi) are audio signal cables, not output cables.

Can a CD player be the source of Hum?

If the answers are yes to questions one and two, it’s likely that one of your sources (like a CD player, turntable, video feed), is the source of hum. Remove that piece from the receiver, amplifier, or integrated and the system hum should now be gone.