Noise Within the Dialogue Unable to Remove

[Graham Bernard]

In Izotope RX there is a HUM Removal module. Have to tried it?

Grazie

Video Content Creator and Potter
PC 7 64-bit 16gb * Intel® Core™i7-2600k Quad Core 3.40GHz * 2GB NVIDIA GEFORCE GTX 560 Ti
Cameras: Canon XF300 + PowerShot SX50HS Bridge

[Debbie King]

Hi Grazie:

Yes. When I tried it, it cleaned up some of the hum, but created a new noise; like an echo extending from the dialogue. Kind of like a spring sort of. Even the slightest removal created yet another sound coming from the dialogue, but not on the dialogue.

Many thanks,

Debbie

[Graham Bernard]

[Debbie King] “Yes. When I tried it, it cleaned up some of the hum, but created a new noise”

OK, try removing the HUM first, then Denoise. This way you will know you have removed all that continuous “sound”=HUM prior to then giving RX the task of removing the hub-bub.

I’ve learnt that the ORDER in which I remove noise can bring about unfortunate outcomes – I’m thinking that the “echo” you’re getting is one of those. Hum removal also deals with the harmonics of the hum freq. and it may be these that are being reintroduced when then using HUM RX.

Grazie

Video Content Creator and Potter
PC 7 64-bit 16gb * Intel® Core™i7-2600k Quad Core 3.40GHz * 2GB NVIDIA GEFORCE GTX 560 Ti
Cameras: Canon XF300 + PowerShot SX50HS Bridge

[Bob Peterson]

I apologize if I am explaining something you already know. If so, please disregard my post.

Since you have a denoiser, that should do the job. The trick is that you have to “teach” the denoiser what it is supposed to remove. Find a small section of the audio which contains ONLY the offending noise. Run the learning mode on that section. In preview, that section should now be silent. Then extend your audio selection to include all of the audio, and run the denoiser. It should remove the noise without changing other sounds such as dialogue.

[Debbie King]

Hi Bob:

Thank you so much. That is exactly what I did, which is why I am so perplexed. I always find a spot where there is no dialogue so to not create artifacts in the voice. Somehow, the surrounding noise disappears, but leaves the noise in the voice. BTW, this is not for all of the clips; just a few. For most of the film, I was able to get the noise cleaned up.

Many thanks,

Debbie

[Debbie King]

Thanks Grazie:

Great idea. I’ll try it.

Many thanks,

Debbie

[Bob Peterson]

How much are you reducing the noise, and are you later increasing the volume when the audio is played back?

[Debbie King]

Hi Bob:

That’s a good question. My noise reduction is in increments, but I do sometimes raise the volume of the clip, as I am in the process of leveling. I have a most recent post regarding my confusion between Volume and Leveling that I posted a few hours ago. Should I wait until all levels are in place before the clean up?

Many thanks,

Debbie

[Bob Peterson]

Yes, I think that is your problem. When I increase volume after denoising, there is a point where I can again hear the noise. Also, when I run the denoiser more than once, it is not unusual to begin hearing things that do not sound right. I try to get all of my levels fully adjusted before denoising the audio. I usually can apply a compressor to that result without adverse consequences.

[Steve King]

I agree that one should set the final track level before applying a noise reduction treatment. However, if you are using envelopes on a track to raise some sections and lower other sections, the noise reduction result will be uneven. If you think about it, as you change the level within a track, you are also changing the level of the noise floor. The same could be said of applying a compressor/expander before treating the noise. Noise reduction tools don’t do well with that either. In my experience, noise reduction is always a compromise between minimizing unwanted background noise and how much digital artifacts on the wanted audio you can tolerate. Sometimes two passes of moderate noise reduction provide better results than a single more severe treatment. Some software and hardware solutions are better than others. I regularly use the noise reduction feature of Adobe Audition 3.0. In the past I have used Sound Forge. Both are remarkably good. I haven’t tried Vegas Pro’s audio restoration Fx. I should do that. I’ve listened to before and after audio treated with Cedar’s hardware solution… stellar!

Steve K
Full time writer/director
Pt. Time Video Editor