Horizontal line in Spectrogram view

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pdun459
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Horizontal line in Spectrogram view

Post by pdun459 » Fri Feb 24, 2017 5:51 pm

Would anyone know what this horizontal line means? I've been noticing it in a few files. I just started working more with Spectrogram view so there's still a lot I'm uneducated on. Thanks.
Spectrogram.jpg
Spectrogram.jpg (70.92 KiB) Viewed 783 times

kozikowski
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Re: Horizontal line in Spectrogram view

Post by kozikowski » Fri Feb 24, 2017 6:08 pm

That would be a constant tone or scream at about 16000. If you're old enough you might not even hear it. Back in the analog TV days, some TVs would scream at that tone. It drove dogs nuts. Some lighting systems run, and scream at that rate. Motor systems? What in your environment could be making that noise?

Turn stuff off and see if it goes away. If you really offend the sound gods, your computer is making that noise.

Koz

kozikowski
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Re: Horizontal line in Spectrogram view

Post by kozikowski » Fri Feb 24, 2017 6:12 pm

If this is a live microphone, start a recording and move the microphone. See if, for example, it gets worse near your monitor.

Koz

pdun459
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Re: Horizontal line in Spectrogram view

Post by pdun459 » Fri Feb 24, 2017 7:31 pm

The file is a song I ripped from a commercial CD. Are you saying it's not necessarily in the recording but coming from an external source?

Edit: I think I see what you mean. Probably something in the environment when the recording was made? As long as I can't hear it not really anything to stress about?

DVDdoug
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Re: Horizontal line in Spectrogram view

Post by DVDdoug » Fri Feb 24, 2017 8:06 pm

Edit: I think I see what you mean. Probably something in the environment when the recording was made?
Yes. Probably a CRT video monitor in the recording studio.

And, it's probably an older recording when they were using CRTs and before everybody had digital spectrum analyzers. It's high-enough in frequency and low enough in amplitude that it wasn't heard and it wasn't a problem.

Trebor
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Re: Horizontal line in Spectrogram view

Post by Trebor » Fri Feb 24, 2017 8:22 pm

IMO it's a digital artifact, rather than an acoustic phenomenon.

A notch filter will get rid of it if it's causing a problem,

pdun459
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Re: Horizontal line in Spectrogram view

Post by pdun459 » Fri Feb 24, 2017 10:28 pm

It's from Blue Oyster Cult's first album, recorded in 1972, probably on the cheap. I checked every track and they all have that line. It would probably be better if it wasn't there but it's nothing major. It's not one I listen to a lot these days.

Many thanks! :)

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