Realtime Noise Filtering software?

Discussion in 'Tracking / Mixing / Editing' started by cyris69, Dec 30, 2012.

  1. cyris69

    cyris69 Active Member

    Ok, I'm not sure where to exactly post this but I figured this is a great site to ask the question.

    I recently purchased my first microphone (Blue Yeti) and want to find a software solution to do some sort of real time filtering of white noise (particularly computer fans) so I can stream over xsplit for my gaming live streams, on teamspeak, etc. I don't do this for money so I want something cheapish or freeware.

    I've found this very hard to google for as most things are for fixing already recorded audio.

    I have the gain all the way down and about 1.5 ft distance between me and my mic also only use cardioid mode. Having a highend gaming computer makes for quite the fan noise used in cooling.

    Thanks in Advanced!!
     
  2. RemyRAD

    RemyRAD Well-Known Member

    Your request is a bit difficult to fill. Most noise reduction programs need to sample a small isolated section of the noise so as to develop a noise print. And so the noise reduction is then performed after the fact. I know of no software that provides for real-time noise reduction? However there are certain pieces of software that allow their effects to run in real time but not from incoming source material.

    In the past, we had some real-time white noise in reducers. These devices were a sliding filter and were equivalent to inverse dynamic equalization. So until there was material of high frequency materials such as the sibilance that many words possess, the filter would remain rolling off the high frequency response until it sensed those higher frequencies, in which case, the filter would open dynamically. DBX has a unit that does this, Berwyn and consumer products such as SAE, BSR and others also offer these sliding dynamic noise reducing filters. I have a couple of these. But also a simple downward expander also works out quite well even though it is a broadband device. You set the threshold so it only opens up upon your speech and closes down after you finish speaking. It could be a gate or a downward expander, both will accomplish the same thing. The downward expander can be a little more gentle since you can set how far down you want the expansion. I find that 10-20 DB, is all that's necessary. A gate, just slams the door closed and then slams open closed, then open, then closed. And without some other kind of audio mix in over top, it can sound pretty obnoxious. So they gate would work well if you had some low-level music behind you. The downward expander would be necessary without any background music, so as to sound normal.

    Of course hardware devices like that, require an external microphone preamp or mixer. These devices do not have microphone inputs but only line level inputs.

    For an effective signal chain to process your microphone with and to lower the noise, you may need to assemble a type of channel strip? This would include the microphone preamp and any necessary phantom power for condenser microphones. The preamp would then be plugged into a compressor/limiter that may also include a noise gate such as a DBX 266/166. Nothing else really need to be done unless you would want some equalization for your microphone? Then you might want to purchase an additional outboard equalizer to passion either before the compressor limiter gate or after? And this type of a signal chain would not be much different than what folks like Howard Stern, Rush Limbaugh had all of those others use for their live broadcasts. It gives you a really slick, smooth, pumped up quality to your voice. Makes you sound very authoritative. And you can even accomplish this from a simple cheap multimedia headset/microphone combo thingy costing as little as six dollars US. Stick an extra piece of foam on those $.98 microphones and you won't believe what you can get.

    There has been some software in the past that has allowed one to use it as an effects processor as if it was a piece of hardware in a rack. Steinberg Wave-Lab made that feature available back in version number 4. Not sure if that is still a feature offered in their most recent release? Of course there is a slight amount of latency that you might have to change in your software buffer settings? Just to minimize the latency so you can talk without losing your mind.

    Unfortunately, as cool and as control room like as computers are, they actually miss a lot of the functionality that can be had with rather costly outboard hardware. However there are those pieces of software that do allow for real-time effects monitoring such as the PreSonus Audio Box USB 2.0 device costing about $250 US. This particular box, with its USB 2.0 speeds and a modern day computer, may also be able to fill the bill? Not sure though if they have a dynamic section to allow for adjustable downward expansion or sliding dynamic filtering? But I believe there is some of that in their Studio One version 2 software that is supplied. And it is awesome multi-tracks software that rivals Pro tools and others. But as to a real-time sliding dynamic noise reduction filter plug-in, I really haven't seen any of those. But with a dynamics processing program that allows you to draw your own dynamics processing GUI and you can adjust the low and high frequencies and a detector circuit, you could effectively make your own real-time dynamic equalizers suitable for white noise oriented noise reduction. But that would take a little skill on your part and some experimenting since there may not be any predesigned preset plug-ins designed to do exactly that function at the junction.

    Me? I use a standard microphone plugged into a microphone preamp with an equalizer. That is plugged into the 1176 limiter. The 1176 feeds the KEPEX 1. And I've been using that since 1978. It's what I use for cutting announcers for commercials, disc jockeys, singing vocalists. The compressor limiter makes it super smooth and pumped up. The noise gate is being used as a downward expander, where I restrict the downward expansion to no more than 10-20 DB. So even when the microphone is off, it's actually still on. But low enough so as not to hear any noise but on enough to not miss anything before the gate swiftly opens. Though learning how to set this by hand, can be a little challenger to those that are new at it?

    If you get something like a DBX 166/266, they gate will appear before the compressor/limiter. While this still works well, it's actually a little trickier. Because if you mumble, they gate may not open up and there will be no compression of your voice and it will be lost. So I generally compressed and/or limit before I insert the gate or downward expander. That way any mumble leading is brought up high enough in level so as to open the downward expander. The downward expander or gate threshold level becomes critical. You start with the gate closed. Without speaking, you start increasing the threshold sensitivity level of the gate until it just fires open. Then you back that control down so that the gate is closed. This will ensure that the microphone is off, gated or, downward expanded to a lower level of in-audibility. With your first utterance they gate or downward expander will then immediately open.

    When you stop speaking, you will also have a release speed control. You have to adjust this by ear so that it effectively tracks the envelope of your voice. Too slow and you'll hear the background noise fading out. Too fast and certain words and consonants will be truncated, with the ends of words cutting off too quickly and will sound very unnatural. Generally around 50-100 ms release times work out well for spoken word. And it really tightens you up. With the downward expander or gate adjusted just right, you could also reduce if not completely eliminate your breaths from sounding like you are gasping for air from asthma LOL. In the past, people actually sliced tape to eliminate breaths. I found that a huge waste of time back in 1978 when I finally purchased my first KEPEX 1 from Allison Research. I have eight. 4 original release units and their later release units. The difference being, the early units use neon bulbs to indicate different levels of gain reduction. So not only did you need the 24 V power supply, if also required 100 V, to light the neon bulbs. So I converted those over to the LED that the later units had. Those don't require 100 V with LED's, just +24 VDC.

    Basically these things just work backwards from a compressor limiter. But when you supplement them with a compressor limiter, you get an awesome vocal sound.

    PreSonus also has a specific microphone channel processor. I can't remember if they offer any kind of noise gate/downward expansion? So you can check it out at their website.

    DBX has a nice processor they used to make that you can still find called the 286. I've installed that for some of my clients voice over booths. And it basically does everything you needed to do that I've described. It's got a nice microphone preamp with phantom power and a high pass filter. It then goes into a nice over easy knee compressor. That's followed by a high frequency articulation enhancer. Followed by an adjustable downward expander/gate. And as I recall it was around the $250 US area. I believe there is 386 is a similar device offering other enhancements and for a higher sticker price.

    One other rudimentary circuit ya might try to find, is a simple circuit they use for voice operated communication microphones known as VOX? This is the world's simplest microphone gating device originally intended to switch on a transmitter relay. Releasing the transmitter relay a couple of milliseconds after speech has stopped.

    There are companies like Cedar. They offer a real-time noise reduction box that will do exactly, perfectly, what you want it to do. They also offer software with numerous different noise reducing capabilities. It's a little over $3500 I think maybe 5000? It's used on live network television shows.

    That's the best I can offer up for ya. There may be other suggestions from others?
    Mx. Remy Ann David
     
  3. cyris69

    cyris69 Active Member

    Thank you for your extremely informative post. Being a none audio tech savvy person I understood maybe a few percent of the post. It is quite apparent you know your stuff and I am very thankful for your post and will read it several times and do more research on what you have given me.

    It seams the only way is to spend quite a lot of many to reduce my fan noise issue :), I might look into moving my PC to a closet or getting quieter fans. I'm on a VERY low budget, as seeing many rack options are now moving to software based applications I was looking at Waves Z-Noise which does real time removal but I can't figure out how to run it as I don't have a Host application which makes me think there is no real way to pass it on. I was going to try a onboard mixer app to do this:
    Mic > Noise Removal Software > Output To VAC line > Streaming software

    Also looked at the iZotope ANR-B which does this but obviously WAY out of my price range.
    iZotope ANR-B: Adaptive Real-time Noise Reduction Hardware - YouTube

    I guess I had my hopes up for some magical lowend software for $100.
     
  4. audiokid

    audiokid Staff

    Amazing post Remy.

    To the OP,
    I use a gaming CP for mastering. Its actually a server that I purchased for running mass sound libraries. It never gets hot so the manufacturer who custom built it suggested I just disconnect some of the fans. If they start speeding up, that would tell me it needs more connected. Gaming PC get a lot hotter. .

    You never need a video card with a fan for audio either.

    You can also build a box with sound treatment and put your CP in that. I have one with a very slow speed fan in it with an inlet and exhaust like a house dryer that goes out to another room so you cannot hear it at all.
     
  5. cyris69

    cyris69 Active Member

    I guess I can ask this, do you have a recommendation of a under $100 highly directed cardioid mic? Or a mic that has a smaller field of pickup for voice? I guess it doesn't have to be cardioid but I assume that's the only real option for voice capture. I assume that may resolve some issues of white noise?

    I've never use sound dampening things before, is there a cheap solution to make this box without causing airflow issues? Maybe a link explaining how to do this? Are you talking about something like dynamat for car audio?
     
  6. RemyRAD

    RemyRAD Well-Known Member

    Really quiet running fans are also not cheap. White noise is a function of the microphone amplification circuitry itself. If you're talking about air-conditioning noise and the fans themselves, some of that can be lessened with something such as the SHURE SM58. The microphone you currently have actually picks up everything you don't want in that room. And this de rigueur microphone with a simple XLR to USB adapter will solve most of your problems. And you should be about 3-5 inches away from the microphone. Any further than that and you will be simply amplifying all of the noise in the room from your computer fans.

    Companies actually make specialized soundproof boxes in which to place your noisy computer. It is outfitted with its own quiet running air circulation fans. They ain't cheap either. Quite frequently, computers that we get for our audio work are outfitted with extremely quiet fans. We can't have that kind of a racket in the control room either.

    If you disconnect your fans, while the device may work for you while, heat is an absolute killer. And you can expect a foreshortened lifespan of that equipment. One other thing you might want to try that would be relatively inexpensive, is to go down to your local Radio Shaft and pick up one of those wire wound speaker volume controls. They are 8 ohms. Connect one of the outside tab connections to the middle tab connection. Split the wire on the fan and wire that side up. Attach the wire to the other extreme and connection tab. And just try dialing back the speed and the racket that the fan makes. It would be better to have a little air circulation rather than none. And that will likely cost less money than replacing the fan/fans?

    Nevertheless, if you are enrolled to be close proximity to that microphone, just background noise really shouldn't be that much of a problem. You may have turned the microphone up too loud and are therefore over amplifying your background noise. If the computer is right there next to the microphone, no wonder you're having a problem. Put it on the carpeted floor. Throw a blanket over it. Make sure not to block the fans. And you should be good to go.

    Have you considered a multimedia headset with microphone? You know there are some better ones than the average run-of-the-mill crap? And they also feature noise canceling microphones. Companies like Beyer make the ones you see all the sports casters at the football stadiums wearing. And they have to cancel enough of the raucous noise so you can hear the announcer. And they are broadcast quality microphones. Again, not cheap. In fact rather pricey. But you get what you pay for and you got the wrong thing.

    What is it that you are using this for exactly? For professional announcements that you are recording? Real-time chewing the fat with your friends around the globe? Screaming " I got you sucker! ", after you zap him with your Ray gun or M-16? You are designing video games and you want to be the voice of God, for the videogame? What? What really is the problem here? Certain microphones like yours, are designed to be more sensitive to everything. Probably not smart knowing you had noisy fans? Didn't think about the fans did ya? No.

    When the software says it works in real time, that's a little deceptive. It works in real time on pre-recorded tracks. It does not work in real time to a real-time input source to output. It's real-time if you use programs like Avid, ProTools and others that can handle real-time processing of pre-recorded tracks. So unless you understand audio software, you might as well hang it up.

    The one way noise reducers by DBX you can find for around $150 used on eBay. You might be able to find consumer style BSR/Metro Tech and a couple of others that I mentioned earlier for around the same price or less on eBay. These devices actually work exceedingly well. What you don't know is, your noisy fans will be heard, when you speak. It will modulate behind your speaking. So you either quiet the computer down, and close it, cover it up, purchase some quiet fans and you may do better. Not adjusting the level properly on that microphone, you'll still be plagued with lousy rooms sound and other noises all around you. If this were easy, anybody could do it. But we needed to be specially trained which required us to drop out of high school. Though it's taken us a while to figure out how to spell supercalifragilisticexpialidocious. But that is the correct spelling. It's only taken me 40 years to learn how to use my voice recognition software. I can't even spell juxtaposition wrong anymore. What's with that?

    I think I'm having a Myoldcardioid infuction after that answer? Could some of you please call the Hyper Cardiologist? This seems to be a Dynamic event and I am only holding on by a thin little Ribbon.

    I think I need to be Degaussed?
    Mx. Remy Ann David
     
  7. cyris69

    cyris69 Active Member

    :) I guess I really didn't know what to expect in terms of background noise. I wanted to find a popular but budget friendly microphone for everyday use, not interested anymore in headsets and prefer a nice pair of cans. I use it mainly for voip software such as teamspeak to chat with friend whom play DayZ together as well which is very tactical and needs a clear mic. I Live Stream my feed over xsplit to twitch.tv so its like a live video capture podcast. I wanted something that would pick up my voice very clearly and accurately which the yeti does flawlessly. I don't really like having the microphone so close ~6 inches or less to my face. I find it picks up my voice very well at ~2 feet without upping gain or input volume. I'm going to attempt to mount it on the wall next to me so it will be ~1ft or less from my face but not obstructing my dual monitor view or keyboard access. This was a free mic for me,

    My microphone sound volume is set at 25% on my PC and the gain is at 0 on the mic. I have several gaming performance fans (6 of them) in my case which are rated at 45dbA at full speed. I run them at 2200/3000 rpm they are capable of.

    I uploaded a sample to my mediafire premium account, I could not find another place to upload it for play.
    http://www.mediafire.com/file/n9demd8rawpo88u/backgound_noise.wav

    I find the background noise acceptable but thought there might be a cheap way of removing some of it. I'm completely new to the mic scene, I am quite the audiophile when it comes to cans and speakers just new to mics. I will work on solving the issues (fans, etc) which shouldn't be too hard. I have some dynamat laying around and will try and do something with it.

    You wouldn't happen to know of a cheap swivel mount would you so I can mount it to my wall and be able to slightly adjust position?
     
  8. RemyRAD

    RemyRAD Well-Known Member

    Markertek has everything you could possibly want like that wall mount mic arm for radio.

    Remy
     
  9. pan60

    pan60 Active Member

    I would think isolating the computer as best you can and get a more focussed hyper cardioid mic, and get on top of it.
    I would be the last person to know much about software to help you but I really do not believe software is the solution.
     
  10. dvdhawk

    dvdhawk Well-Known Member

    I like that idea of a little gobo to block the direct path of the sound into the mic (without blocking its ventilation), in combination with Remy's suggestion of a noise-cancelling mic. There are scads of cheap noise-cancelling mics on the market these days for telecom and gaming.
     
  11. thatjeffguy

    thatjeffguy Active Member

    I once built an isolation box for my computer, it's not hard and not expensive. You just need to design a maze of sound-deadened baffles into it and include a silent fan that is powered by the PC. Air in & out was at the rear of the box. This reduced the noise from the computer to nearly nothing. Barely a half-sheet of 1/2" plywood and some foam rubber. You can do this!
    Jeff
     
  12. JohnTodd

    JohnTodd Well-Known Member

    For my noise removal I always make sure there is "dead air" at the beginning of the take, so that I can have a nice long noise print. Works great, but the best thing is not to have the noise to begin with.
     

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