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Really bizarre question on EQ'ing
Old 4 weeks ago
  #1
Here for the gear
 

Really bizarre question on EQ'ing

This might be the most ridiculous question ever asked on this forum, but here goes. I work for a private detective, and my job is to bug cars. Literally, I install these S. Korean audio bugs about the size of D battery inside of a vehicle, and they have a battery life of around 3-5 months. They use an omni mic and are voice activated. At the end of the surveillance, I remove the bug and download the mp3 files it recorded. Sometimes it's weekly or monthly, other times that frigging thing will sit in there for months. The deal usually is, you know, cheating spouse, suspicion of drug use, usually marital BS. Anyhow, trial and error has led me to place the bugs (they have a magnet) on the metal passenger seat runner, due to the fact that most people are righties...so if a passenger drops something, it'll usually be on the right hand side and not the left side (hence the bug won't be felt by somebody reaching around for the pack of cigarettes or whatever they just dropped). The small omni mic points upwards from that position and records.
So after the bug is removed, I record the time stamp as the file name for each mp3, and quickly convert the file to .wav via Audacity, then import the .wav file into Reaper for cleanup. And this is where the fun starts. Different cars produce different amounts of just baseline wind noise, Subaru being by far the worst. Then in the spring and summer I'll get A/C noise, or in the winter I'll get the heater blowing at full blast. Or maybe a smoker who opens their window for 10 minutes every time they smoke a cigarette. Every once in a while I'll bug a car with a noisy trans or loud muffler, but that's usually no big deal compared to wind noise. Usually what I do is begin with one of Reaper's ReaEQ presets (maybe "Mud Free" for example), and work from there to try and tweak the wind noise to be as low as possible. It takes HOURS.
But my question is, is there any more scientific and professional way to approach trying to get wind or blower noise out of a single channel recording? It takes me LITERALLY HOURS. Not long ago a guy paid us to spy on his cheating wife, who had her phone Bluetoothed to her car stereo...so whomever she called would sound so ridiculously loud in the recording coming through the radio's speakers, but her own voice was barely audible no matter what I did. So i had a loud male voice and then a barely audible female voice that I'm supposed to turn into an audible conversation. Compression maybe? I'm at a loss here fellas...any ideas as to how I can EQ out wind noise from a single track panned at 12, recorded with a crap omnidirectional mic.

BTW changing the voice-activation sensitivity did nothing. This is going to have to be fully post-production here.

This is the most ridiculous question here ever for sure so feel free to make a joke or two (I joke about my job all of the time) but please, some helpful hints as well please?
Old 4 weeks ago
  #2
Here for the gear
 
MarAtaSe9's Avatar
 

Quote:
Originally Posted by Krinkov58 View Post
This might be the most ridiculous question ever asked on this forum, but here goes. I work for a private detective, and my job is to bug cars. Literally, I install these S. Korean audio bugs about the size of D battery inside of a vehicle, and they have a battery life of around 3-5 months. They use an omni mic and are voice activated. At the end of the surveillance, I remove the bug and download the mp3 files it recorded. Sometimes it's weekly or monthly, other times that frigging thing will sit in there for months. The deal usually is, you know, cheating spouse, suspicion of drug use, usually marital BS. Anyhow, trial and error has led me to place the bugs (they have a magnet) on the metal passenger seat runner, due to the fact that most people are righties...so if a passenger drops something, it'll usually be on the right hand side and not the left side (hence the bug won't be felt by somebody reaching around for the pack of cigarettes or whatever they just dropped). The small omni mic points upwards from that position and records.
So after the bug is removed, I record the time stamp as the file name for each mp3, and quickly convert the file to .wav via Audacity, then import the .wav file into Reaper for cleanup. And this is where the fun starts. Different cars produce different amounts of just baseline wind noise, Subaru being by far the worst. Then in the spring and summer I'll get A/C noise, or in the winter I'll get the heater blowing at full blast. Or maybe a smoker who opens their window for 10 minutes every time they smoke a cigarette. Every once in a while I'll bug a car with a noisy trans or loud muffler, but that's usually no big deal compared to wind noise. Usually what I do is begin with one of Reaper's ReaEQ presets (maybe "Mud Free" for example), and work from there to try and tweak the wind noise to be as low as possible. It takes HOURS.
But my question is, is there any more scientific and professional way to approach trying to get wind or blower noise out of a single channel recording? It takes me LITERALLY HOURS. Not long ago a guy paid us to spy on his cheating wife, who had her phone Bluetoothed to her car stereo...so whomever she called would sound so ridiculously loud in the recording coming through the radio's speakers, but her own voice was barely audible no matter what I did. So i had a loud male voice and then a barely audible female voice that I'm supposed to turn into an audible conversation. Compression maybe? I'm at a loss here fellas...any ideas as to how I can EQ out wind noise from a single track panned at 12, recorded with a crap omnidirectional mic.

BTW changing the voice-activation sensitivity did nothing. This is going to have to be fully post-production here.

This is the most ridiculous question here ever for sure so feel free to make a joke or two (I joke about my job all of the time) but please, some helpful hints as well please?

Hi there----> "Noise Reduction" plugins in your DAW should be spot on for this

Reaper has one in their list of cockos plugins as "ReaFir" but its not particularly obvious at first glance how to work it; tons of other companies make intuitive versions if you need a quick fix at the moment (Klevgrand's "brusfri" takes like 5 seconds to figure out)

You just select a portion of your recorded audio that doesn't have dialogue and "capture" via the plugin---the plugin learns the frequency profile of the unwanted audio (anything that isn't dialogue), and you can then adjust how much of the capture frequency profile is removed from the track/file (* frequency specific audio gating basically). Its magic

Old 4 weeks ago
  #3
Gear Guru
 

Quote:
This is the most ridiculous question here ever for sure so feel free to make a joke or two (I joke about my job all of the time) but please, some helpful hints as well please?
Not a joke but a comment: I am not a lawyer, but I am related to several lawyers and former ADAs. What you are doing strikes me as sketchy as hell. In most states, you can only covertly record a conversation that you are a party to ... but recording 2 other people, in their car? I don't know... Even the police need a court order to plant a bug.

Do you break into these cars to install your bugs and then break into them agan to retrieve them? What value do these recordings have to the "client"? If the activity of obtaining the recordings is illegal, how can the information they provide be used in court for divorce or custody proceedings etc. ?

It is possible that your employer may be the one held most responsible for any criminal charges or lawsuits arising from illegal eavesdropping, but since you are the one actually planting the bugs, I would guess that your position might not be exactly risk-free.

Quote:
I joke about my job all of the time
I don't know what country or state you live in, but you may find yourself in a situation that is no joking matter. If I were you, I would find an attorney (one that does not know your employer!) and at least consult with him about your exposure. Now.

Before you need an attorney.
Old 4 weeks ago
  #4
Here for the gear
 

Thank you for your replies!!!!

Joeq, you are 100% correct in most of what you said. We don't touch a vehicle until we see a lien-free title in our clients name, and even then there is a whole hell of a lot of legal paperwork to sign. If a client wants an audio device in their car, it's the same as an alarm system. Or those doorbell cameras they have now that capture people walking by without their consent...police can use images from those in certain cases even if the situation doesn't involve the house the camera is attached to. Hell, ATM cameras are used out of context in court all the time if they happen to record something in the background pertinent to a criminal complaint. We are all under a certain degree of surveillance as soon as we step out our front door. Traffic cameras, security cameras on businesses, etc.

The recordings, even though obtained through legal means, are NOT used in court. Any moron defense attorney would have them thrown in the trash at the first hearing. They're used to confront the offending party and leverage them into a deal, in the case of say, some old guy's trophy wife is banging her Pilates instructor on the sly. Sometimes there are kids, houses, millions of dollars at stake. Divorce court is expensive...we advise clients to just "cut and run" by leveraging a deal with as much evidence as possible, offer a fair amount of money as a severance, and split. We do GPS and video as well...I mean, there are even websites you can hire people with fake social media profiles to try and bait your spouse into cheating. It's an entire industry, man. Yeah sometimes the law is skirted but we are only allowed to do so much, believe me, we get offered crazy money to do crazy things. Check around the internet and you'll hear plenty of nutty stories from people in the industry.
Old 4 weeks ago
  #5
Gear Nut
For EQ-101, the basic technique is to raise a freq band until you find the freq where the noise you don't want is really offensive, then lower that band. Of course, a good noise reduction plugin with get you farther faster.
Old 4 weeks ago
  #6
Gear Guru
 

Quote:
Originally Posted by Krinkov58 View Post
Thank you for your replies!!!!

Joeq, you are 100% correct in most of what you said. We don't touch a vehicle until we see a lien-free title in our clients name, and even then there is a whole hell of a lot of legal paperwork to sign. If a client wants an audio device in their car, it's the same as an alarm system. Or those doorbell cameras they have now that capture people walking by without their consent...police can use images from those in certain cases even if the situation doesn't involve the house the camera is attached to. Hell, ATM cameras are used out of context in court all the time if they happen to record something in the background pertinent to a criminal complaint. We are all under a certain degree of surveillance as soon as we step out our front door. Traffic cameras, security cameras on businesses, etc.

The recordings, even though obtained through legal means, are NOT used in court. Any moron defense attorney would have them thrown in the trash at the first hearing. They're used to confront the offending party and leverage them into a deal, in the case of say, some old guy's trophy wife is banging her Pilates instructor on the sly. Sometimes there are kids, houses, millions of dollars at stake. Divorce court is expensive...we advise clients to just "cut and run" by leveraging a deal with as much evidence as possible, offer a fair amount of money as a severance, and split. We do GPS and video as well...I mean, there are even websites you can hire people with fake social media profiles to try and bait your spouse into cheating. It's an entire industry, man. Yeah sometimes the law is skirted but we are only allowed to do so much, believe me, we get offered crazy money to do crazy things. Check around the internet and you'll hear plenty of nutty stories from people in the industry.
Ok - well as long as you know where you stand. I guess if a guy bugs his own car it's legal, but it seems to me, if the wife was smart she could find out what was admissible in court, instead of caving at the "confrontation".

Quote:
But my question is, is there any more scientific and professional way to approach trying to get wind or blower noise out of a single channel recording? It takes me LITERALLY HOURS.
Izotope RX is the standard for this type of thing. Removing steady-state noise like fans and motors and wind is actually one of the things it does best and easiest. You need a sample of the noise 'in the clear' - perhaps in a pause in the conversation. You play that noise into the software and it "learns" what you consider noise and removes it from within the audio. It's not like a gating thing where the noise comes back up with each word. It is truly miraculous and is something I used to tell my students was "impossible".

There is also a spectral editor that can be used to extract vocals from a full song mix. This may rely a lot on pitch and may not work as well for extracting conversational vocals, but worth a try. In the spectral editor, each frequency within a sound is represented visually. You can draw a box around something you think is wanted or not wanted and save it or remove it.

I had a guy who wanted the sound of some ducks near a waterfall, but he wanted the waterfall taken out.... no problem! I had a poetry reading where the recorder was set up near the air conditioner... no problem. I have gotten AC hums out and tape hiss out. I have also gotten one-off sounds out - like the "thump" of the pedals on a grand piano. Or a dog bark.

There is a demo, I don't think you will be disappointed.

Last edited by joeq; 4 weeks ago at 07:01 AM..
Old 4 weeks ago
  #7
Here for the gear
 

Joeq thanks, downloading the 10-day demo now. Yeah gating never worked for me either as far as wind noise goes.

And wives/husbands aren't always that smart...plus, there's the embarassment of going through court proceedings regarding cheating, etc. with kids and family involved. Or plenty of times, it might be a registered company truck being bugged because an employee is doing something stupid on company time. You just never know what it'll be.
Old 4 weeks ago
  #8
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badmark's Avatar
Quote:
Originally Posted by Krinkov58 View Post
... I work for a private detective, and my job is to bug cars.
Yo, that's quite the calling card you just chucked down there. The only private detective I've ever come across was in a charity shop in Edinburgh, he was asking the shop worker if the woman who'd just left had given her any cutlery.


Quote:
Originally Posted by Krinkov58 View Post
...
Anyhow, trial and error has led me to place the bugs (they have a magnet) on the metal passenger seat runner, due to the fact that most people are righties...so if a passenger drops something, it'll usually be on the right hand side and not the left side (hence the bug won't be felt by somebody reaching around for the pack of cigarettes or whatever they just dropped). ...
now that's what I call a pro tip

Quote:
Originally Posted by Krinkov58 View Post
...
... Not long ago a guy paid us to spy on his cheating wife, who had her phone Bluetoothed to her car stereo...so whomever she called would sound so ridiculously loud in the recording coming through the radio's speakers, but her own voice was barely audible no matter what I did. So i had a loud male voice and then a barely audible female voice that I'm supposed to turn into an audible conversation. Compression maybe? I'm at a loss here fellas...
The simplest (tho' yeah time-consuming) way in Reaper awould be to split the audio onto two mono channels and sub-track them both into a main track. Normalize each track in 'item properties' to matching levels. Due to the two voices having different noise problems, you could then use separate instances of e.g. the Izotope (business expense?) to clear them up.

If you were, say, preparing your audio files for a podcast then compression would become an issue but for your purposes it's probably a rabbit-hole best not being drawn into.
Old 4 weeks ago
  #9
Here for the gear
 

Reaper has built in spectral editing which as mentioned above could help.

Audacity has a Noise reduction Effect that like RX takes a sample of audio and tries to deduct the noise from the audio clip.

I listened to an old podcast a few months back (might have been twenty thousand hertz) where they did an interview section with a forensic audio engineer who was able to demonstrate the ability to remove a very noisy fan and and a loud television from a bugging recording (even going as far as getting the TV broadcast and negating that from the surveillance) to provide a very clear version of the dialogue.

SoS had an overview of the sort of techniques used including RX here: https://www.soundonsound.com/techniq...io-engineering
Old 3 weeks ago
  #10
Gear Nut
 
bmanzer's Avatar
I hope you come back and tell us what worked and how well.
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