Directional headset microphone? (dealing with street noise) - Page 1
Forum section: electronics / general

author: ivan747
author_rank: Super Contributor
timestamp: March 20, 2015, 08:08:06 pm
content: Hello guys!My stepfather needs some sort of directional microphone solution so that he can make long conference calls with his clients on Skype. It *HAS* to be very directional and noise cancelling. The reason for this is because his office is just in front of the street, and has lots of glass, and generally poor sound isolation (we can look into that as well in this thread).My developing country has very poor laws and regulations regarding the noise that vehicles make, so every once in a while we get someone passing by on a motorcycle with a blown muffler, or one of these blokes passes by:the guys in the truck normally use megaphones to sell their products, the guy in the tricycle usually has very large lungsThere's very little one can do about this, apart from moving to a closed gate residence. It's ingrained in this country's culture and economy.Back to the mic...Now you know what he needs it for. Basically he wants only his voice to be heard. I thought about some sort of figure 8 microphone and acoustic panels on the walls, like this:But I am looking for suggestions. If you guys know a good sound/microphone forum (not audiophile stuff), please recommend it to me.He's planning to spend about US$100, but since he constantly gets embarrassed about the noise, I bet he can stretch the budget the next time noise happens. Something as durable as possible, please.Thank you very much-Ivan

author: ConKbot
author_rank: Super Contributor
timestamp: March 20, 2015, 08:28:00 pm
content: What aboutIve seen a few variations of this build. Obviously if the skype call is voice only its fine. If its a video conference, the box in front of your face may be a bit of an obstruction. Cheap to try, at least.

author: ivan747
author_rank: Super Contributor
timestamp: March 20, 2015, 08:41:07 pm
content: Quote from: ConKbot on March 20, 2015, 08:28:00 pmHe rarely uses video, I think. If he IS using video, normally is such an important call that he moves out of the office into a more silent room.So that can be an alternative. Jeez, he could even place the webcam on top of that!Sounds like a plan.Quote from: blueskull on March 20, 2015, 08:24:44 pmMacbooks are great, but built-in microphones are crap everywhere, even the MacBooks I have tried aren't very good, although they are better than most PC micrphones.He has done Skype calls via cellphone, and it works, but it's not practical for him, sadly. He needs to type on the keyboard very often.What else is out there?I think 2 solutions could be:*Use the sound booth on that youtube video, along with a standing microphone*Use a headset like the ones pilots use

author: Marco
author_rank: Super Contributor
timestamp: March 21, 2015, 03:07:43 pm
content: There are a couple of low cost beamforming microphones on the market.

author: David_AVD
author_rank: Super Contributor
timestamp: March 21, 2015, 10:19:19 pm
content: A head worn microphone with noise cancellation will be his best bet. Having the mic close to the intended source (your mouth!) is essential when dealing with problems like this.

author: ivan747
author_rank: Super Contributor
timestamp: March 21, 2015, 10:30:14 pm
content: Do you think he will get a better chance if he gets a more professional level set? The kind used in call centers,like so:http://www.headsetsdirect.com/I also discovered acriticalproblem with soundproofing in the office. The office is just a small extension of our house, and it is at the front. The house has a very large 10 feet (about 3.3 meter) wide sliding glass door at the front, meters away from the office. When that's closed you can't hear as much noise from the outside. But this didn't happen in the office. In the office no matter what you do it's almost as noisy as having all windows open. The office has two sliding glass windows of the same kind, one is about 4 meters long, the other one is two. They kind of look like this:Turns out that the sliding doors have some sort of felt, hairy fabric lining that seals it on all the edges. The windows in the office don't. No wonder why he got them cheap. The sliding doors are not sliding very well so when we get those repaired we're gonna get the technician to install the thing that seals in the office. That should isolate a lot of noise.

author: David_AVD
author_rank: Super Contributor
timestamp: March 21, 2015, 10:33:53 pm
content: It's a common problem with easy solutions such asLogitech noise cancelling VOIP headsets.Look for the small hole in the "non-speaking" side of the mic. That's the noise cancelling port.

author: ivan747
author_rank: Super Contributor
timestamp: March 21, 2015, 10:41:51 pm
content: Quote from: David_AVD on March 21, 2015, 10:33:53 pmAre they really good? I am worried that the "noise cancelling" feature on most of these microphones consists on a noise gate that mutes the audio under a certain threshold.

author: Tinkerer
author_rank: Frequent Contributor
timestamp: March 21, 2015, 11:21:45 pm
content: Quote from: ivan747 on March 20, 2015, 08:41:07 pmYea, may look wierd, but thats a good way to do it. Not sure what kind of furnature he can have in there, but those cloth covered cubicle type walls will absorb alot of sound.

author: Richard Crowley
author_rank: Super Contributor
timestamp: March 21, 2015, 11:38:14 pm
content: REDUCTION - PROXIMITY - CANCELLATION1) Ambient noise reduction.a) If he can move into a quieter room for important calls, why not just move the office there permanently? Especially if clear communications are so important.b) Absorption will reduce the amount of noise reaching the microphone. Noise bouncing around the room is the last thing you need here.2) Proximity. The closer you can get the microphone to the source (the subject's mouth) the better the SNR (signal to noise ratio).A headset microphone is **FAR SUPERIOR** to any other kind of microphone. Repeating: **FAR SUPERIOR*Completely forget using ANY KIND of microphone that is more than 150mm 6 inches away. It will never work.3) Noise cancelling. By using a very close microphone, you can also use acoustic noise cancelling with microphones designed for that.This can ONLY be done with a microphone practically touching the lips.

author: Richard Crowley
author_rank: Super Contributor
timestamp: March 21, 2015, 11:43:27 pm
content: Quote from: ivan747 on March 21, 2015, 10:41:51 pmTrue noise-cancelling microphones do their "magic" acoustically. But they depend on VERY CLOSE proximity to the mouth.The subject speaks into the "front" of the microphone, but the noise hits BOTH the "front" and the "back" equally and results in significant cancellation.Yes there is also the technique of "gating" or "muting" to reduce noise between words, etc. Not clear why that would be undesirable?

author: Richard Crowley
author_rank: Super Contributor
timestamp: March 21, 2015, 11:45:46 pm
content: Those kludgy foam boxes are designed to mitigate the poor room acoustics (typically near reflections) when recording in an otherwise quiet bedroom, office or hotel room. They will NOT have any effect on reducing ambient noise. Feel free to waste money trying it for yourself.

author: ivan747
author_rank: Super Contributor
timestamp: March 22, 2015, 12:52:20 am
content: Quote from: Richard Crowley on March 21, 2015, 11:43:27 pmFirst of all, thank you for the solid advise.The noise gate IS desirable, but what I am trying to avoid here are headsets that rely solely on this and other digital techniques. I'm looking for something that's starts out with acoustics.Sadly, the office is already built, he might only be able to move out of there in at least a couple of years, when me or one of my siblings moves out of the house, to be honest.Quote from: Richard Crowley on March 21, 2015, 11:45:46 pmIt's an interesting experiment (well, for me, I'd like to try that one day, for my own use), but thanks for pointing that out. On the other hand I will probably build some acoustic panels just for fun one day.What I get from you is that he should be using a headset and really soundproofing the room. I'll advise him to wear his current (crap) headset close to his mouth for the moment.Do you happen to know of a good brand, model or type? That way I can start my research from there.Thanks

author: mswhin63
author_rank: Frequent Contributor
timestamp: March 22, 2015, 12:57:07 am
content: How about a throat microphone. I am using one for an application and experience zero external noise. The voice is a bit raspy but intelligible.Quick Google will come up with many suppliers.

author: Richard Crowley
author_rank: Super Contributor
timestamp: March 22, 2015, 01:26:45 am
content: I don't have any experience with the currently available consumer noise-cancelling mics.And I don't know what is available in your country?I would start my research by looking at the user reviews on Amazon, etc.I would have quite low expectation of easily intelligible speech from a throat microphone.I certainly wouldn't buy one if I couldn't return it.

author: Richard Crowley
author_rank: Super Contributor
timestamp: March 22, 2015, 01:30:59 am
content: Perhaps I should not have assumed that sound TRANSMISSION INTO the office is also an obvious method of attack.This is done by either distance (clearly not an option) or by MASS.People use double walls, sheets of lead, triple-pane windows, heavy curtains, double doors, multiple layers of drywall, etc. to cut down on sound transmission.

author: ivan747
author_rank: Super Contributor
timestamp: March 22, 2015, 01:31:44 am
content: Anything sold in the US can be easily imported, but not easily returned.I'll be checking Amazon and some companies' websites.I'll be probably checking the local retail offerings just because they make returns relatively easy.

author: ivan747
author_rank: Super Contributor
timestamp: March 22, 2015, 01:33:55 am
content: Quote from: Richard Crowley on March 22, 2015, 01:30:59 amI have seen double pane windows at uni, they do an AMAZING job. The busy avenue outside is silent from the inside of a 2nd level rool.I'll keep that in mind next time I'm building a office