Directional? Dynamic?
August 17, 2022 3:36 PM Subscribe
I am looking for microphones that will work (e.g. no feedback) with the following setup:
Two laptop computers in a large room (like 100 x 100 feet) facing each other about 10 feet apart, each with a microphone connected to it via USB. The computers are connected via HDMI to a PA system. The microphones should pickup the voice of the person sitting at the laptop and nothing else.
Two laptop computers in a large room (like 100 x 100 feet) facing each other about 10 feet apart, each with a microphone connected to it via USB. The computers are connected via HDMI to a PA system. The microphones should pickup the voice of the person sitting at the laptop and nothing else.
My experience: square dance calling, using a single or dual speaker (so speaker as monitor) set beside me so I can hear it, with a handheld mic, a setup that lets me walk in front of the speaker as long as I don't point the mic straight at the speaker.
I use "hypercardiod" mics, the two in my calling kit are an ElectroVoice EV767a and a Sennheiser e945. I *really* like the e945 for a relatively cheap (~200) performance mic, the EV767a can get a little muddy, and bass heavy. The "hypercardiod" is the bit that describes what the active zone around the head of the mic looks like, "cardiod" is less focused.
To do this with a computer, you'd then want a USB interface that takes XLR in, like a Behringer UMC202HD. Check this out with a borrowed interface and your software, I've had trouble with USB interfaces and non-audio software like Zoom and Google Hangouts on the Mac.
The down-side of this setup is that mic discipline is key: the mic should be a short distance from your mouth, and not move around a lot relative to the mouth. You can do this with stands, but they need to be right in the face of the speaker. The up-side is that you've got the head of the performer blocking the sound in the direction that the mic is most active.
And the particular mic probably isn't as important as that pickup pattern, I'd guess any hypercardiod performance mic is gonna be pretty discriminating and much less susceptible to feedback.
posted by straw at 4:43 PM on August 17, 2022 [2 favorites]
I use "hypercardiod" mics, the two in my calling kit are an ElectroVoice EV767a and a Sennheiser e945. I *really* like the e945 for a relatively cheap (~200) performance mic, the EV767a can get a little muddy, and bass heavy. The "hypercardiod" is the bit that describes what the active zone around the head of the mic looks like, "cardiod" is less focused.
To do this with a computer, you'd then want a USB interface that takes XLR in, like a Behringer UMC202HD. Check this out with a borrowed interface and your software, I've had trouble with USB interfaces and non-audio software like Zoom and Google Hangouts on the Mac.
The down-side of this setup is that mic discipline is key: the mic should be a short distance from your mouth, and not move around a lot relative to the mouth. You can do this with stands, but they need to be right in the face of the speaker. The up-side is that you've got the head of the performer blocking the sound in the direction that the mic is most active.
And the particular mic probably isn't as important as that pickup pattern, I'd guess any hypercardiod performance mic is gonna be pretty discriminating and much less susceptible to feedback.
posted by straw at 4:43 PM on August 17, 2022 [2 favorites]
What about telemarketer-style headsets? Likely USB to boot.
posted by alexandermatheson at 6:00 PM on August 17, 2022
posted by alexandermatheson at 6:00 PM on August 17, 2022
What's the context? Are you looking for highly detailed extreme audio quality, or do you just need to be heard? Unless you need super-duper quality, an inexpensive dynamic mic like a Shure SM58 (about $100) will probably do what you need. If your voice (or really, the PA) is going to be really loud, it might be worth spending the extra on a hypercardioid mic like straw suggested, but even then the SM58 might still be the thing - it's the bread-and-butter mic used by everybody and their cousin for live music performances.
Whatever mic you use, be sure not to place the PA speakers directly behind you!
posted by Greg_Ace at 6:27 PM on August 17, 2022
Whatever mic you use, be sure not to place the PA speakers directly behind you!
posted by Greg_Ace at 6:27 PM on August 17, 2022
(forgot to mention, the SM58 also needs an interface like the Behringer)
posted by Greg_Ace at 6:28 PM on August 17, 2022
posted by Greg_Ace at 6:28 PM on August 17, 2022
Best answer: no feedback
TBH this can have a lot more to do with the positioning and volume of the PA speakers relative to the microphone and the acoustics of the space you are in than the specifics of the microphone. You could get a cheap USB mic and a couple of little computer speakers pointed away from the mic at just enough volume to hit the area directly around the laptops and never get close to feedback. You could have $1000 mics through thousands of dollars of PA system and you'll get nothing but feedback in a 100' square concrete box trying to throw sound to the whole room.
So you'll definitely need to do some consideration of goals and the physical setup. If you want to share more details on that here we may be able to give you some more ideas.
Having said that . . .
Directional?
Yup, generally you want this kind of microphone, meaning that there are "dead spots" where the microphone picks up a lot less sound than the front of the microphone. Cardioid mics have the dead spot at the rear of the mic. Hypercardioid mics have their dead spots in a kind of "V" at the rear. (On an analog clock, if the front of the mic is noon the dead spots would be at the 4 and the 8.) They do pick up sound from the rear (the 6 on a clock) more than a cardioid. These are the two most common types of directional mics. Neither is inherently better or worse than the other, rejection of feedback is a function of where you place your speakers in relation to the dead spots of each type of mic.
Dynamic?
Honestly I'm kinda "eh shrug" about this, depending on your setup and planned usage. Dynamic mics work by basic electromagnetism and don't need any sort of power source, condenser mics require some form of external power source. Very generally speaking condensers are more sensitive in picking up sound, especially high frequencies, and therefore possibly more likely to feedback, but it's quite possible you could get perfectly acceptable results from something like the Snowball USB mic, which is a condenser meant to plug directly into a USB port.
As others have pointed out, a lot of "standard" mics will require an interface of some type to convert from XLR to USB, which will add to the cost of the project.
The computers are connected via HDMI to a PA system.
There aren't really "PA" speakers that connect directly via HDMI, so either you'll need another interface or you're thinking of using speakers that are more "Home A/V" speakers, which may not give you the volume or clarity you want in a 100' room.
mic discipline is key: the mic should be a short distance from your mouth, and not move around a lot relative to the mouth.
STRONG second for this, so if this is a thing where the general public is going to be speaking/singing into the mics you'll want to keep in mind that mic discipline is not a thing they are going to be good at.
This all sounds very "art installation" to me - which is totally cool, I've worked on a few of these - but if so I might consider seeing if you can rent some mics & speakers from a local A/V company and do some experimentation with gear and how it's set up rather than spending that money buying a series of things that don't work the way you want them to.
posted by soundguy99 at 8:26 PM on August 17, 2022 [9 favorites]
TBH this can have a lot more to do with the positioning and volume of the PA speakers relative to the microphone and the acoustics of the space you are in than the specifics of the microphone. You could get a cheap USB mic and a couple of little computer speakers pointed away from the mic at just enough volume to hit the area directly around the laptops and never get close to feedback. You could have $1000 mics through thousands of dollars of PA system and you'll get nothing but feedback in a 100' square concrete box trying to throw sound to the whole room.
So you'll definitely need to do some consideration of goals and the physical setup. If you want to share more details on that here we may be able to give you some more ideas.
Having said that . . .
Directional?
Yup, generally you want this kind of microphone, meaning that there are "dead spots" where the microphone picks up a lot less sound than the front of the microphone. Cardioid mics have the dead spot at the rear of the mic. Hypercardioid mics have their dead spots in a kind of "V" at the rear. (On an analog clock, if the front of the mic is noon the dead spots would be at the 4 and the 8.) They do pick up sound from the rear (the 6 on a clock) more than a cardioid. These are the two most common types of directional mics. Neither is inherently better or worse than the other, rejection of feedback is a function of where you place your speakers in relation to the dead spots of each type of mic.
Dynamic?
Honestly I'm kinda "eh shrug" about this, depending on your setup and planned usage. Dynamic mics work by basic electromagnetism and don't need any sort of power source, condenser mics require some form of external power source. Very generally speaking condensers are more sensitive in picking up sound, especially high frequencies, and therefore possibly more likely to feedback, but it's quite possible you could get perfectly acceptable results from something like the Snowball USB mic, which is a condenser meant to plug directly into a USB port.
As others have pointed out, a lot of "standard" mics will require an interface of some type to convert from XLR to USB, which will add to the cost of the project.
The computers are connected via HDMI to a PA system.
There aren't really "PA" speakers that connect directly via HDMI, so either you'll need another interface or you're thinking of using speakers that are more "Home A/V" speakers, which may not give you the volume or clarity you want in a 100' room.
mic discipline is key: the mic should be a short distance from your mouth, and not move around a lot relative to the mouth.
STRONG second for this, so if this is a thing where the general public is going to be speaking/singing into the mics you'll want to keep in mind that mic discipline is not a thing they are going to be good at.
This all sounds very "art installation" to me - which is totally cool, I've worked on a few of these - but if so I might consider seeing if you can rent some mics & speakers from a local A/V company and do some experimentation with gear and how it's set up rather than spending that money buying a series of things that don't work the way you want them to.
posted by soundguy99 at 8:26 PM on August 17, 2022 [9 favorites]
I'll just mention that the other major way of preventing feedback - other than those mentioned above such as positioning the microphones and speakers, and using various sorts of directional microphones and speakers - is using materials to physically isolate the microphones from sound sources that may cause interference.
So for example, a microphone shield will cut down on sound coming from certain directions and generally help with isolation.
You can also strategically deploy things like acoustic blankets. For instance, an acoustic blanket could be hung in such a way as to block sound from the speaker to the microphone. But also, just deploying acoustic blankets, tiles, etc around the walls and corners (or other furnishings like drapes, carpet, even sofas etc) can reduce reverberation and general sound reflections in the room, which can sometimes help a lot.
There are also kind of small enclosures ("vocal booth" and similar) that would more completely isolate the person and the microphone from the rest of the sound in the room.
posted by flug at 12:32 AM on August 18, 2022
So for example, a microphone shield will cut down on sound coming from certain directions and generally help with isolation.
You can also strategically deploy things like acoustic blankets. For instance, an acoustic blanket could be hung in such a way as to block sound from the speaker to the microphone. But also, just deploying acoustic blankets, tiles, etc around the walls and corners (or other furnishings like drapes, carpet, even sofas etc) can reduce reverberation and general sound reflections in the room, which can sometimes help a lot.
There are also kind of small enclosures ("vocal booth" and similar) that would more completely isolate the person and the microphone from the rest of the sound in the room.
posted by flug at 12:32 AM on August 18, 2022
So you're doing a interview setup with guest at separate tables, both with a laptop for prompts and whatnot, and you're trying to minimize feedback.
If both host and guest are willing to wear headphones, then it becomes much easier as you just need directional microphones. And the Logitech Blue Yeti is known for having multiple pickup patterns with its array of microphones in a single body if you can only use one. But otherwise, any cardiod mic should do fine. However, please put each mic on an arm and test different positioning. You will likely need a mixer of some type though to adjust volumes properly.
As others aid, there are other possibilities, such as isolation shields to block the "back" of microphones, so the host and guest are blocked from each other's voice. But this will require some testing.
The speakers will be the real problem, as you don't want the mics to pick up the speakers.
posted by kschang at 7:05 AM on August 18, 2022
If both host and guest are willing to wear headphones, then it becomes much easier as you just need directional microphones. And the Logitech Blue Yeti is known for having multiple pickup patterns with its array of microphones in a single body if you can only use one. But otherwise, any cardiod mic should do fine. However, please put each mic on an arm and test different positioning. You will likely need a mixer of some type though to adjust volumes properly.
As others aid, there are other possibilities, such as isolation shields to block the "back" of microphones, so the host and guest are blocked from each other's voice. But this will require some testing.
The speakers will be the real problem, as you don't want the mics to pick up the speakers.
posted by kschang at 7:05 AM on August 18, 2022
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The mic can be set to any of three different patterns corresponding roughly to pick up sound from all directions, or mostly from one direction, which is what you want, or two opposite directions which you would use for two person recording.
It's a Sampson Satellite, but I've not gotten enough use out of it to actually recommend it.
posted by SemiSalt at 3:53 PM on August 17, 2022