Record a room with people without miking them individually

[Jacknife27]

Hey I need to record a room of up to 20 people.

(Its a so called hybrid seminar in which some people are participating via zoom and some are physically attending it). The goal is that the people in the room are audible to the people in the zoom call.

So far one omnidirectional mike produced mediocre/bad results. One thing that I thought about was using 2-4 omnidriectional mikes instead, however my budget is only about 200€ so Im not sure wether thats even an option. Would it be better to buy a single but good microphone?

The room is about 6x12 metres big.

[Mickster]

What equipment (other than the mics) are you using to record with? Audio Interface....PC.....mixer. I think that adding a couple more omni mics would help your cause if they're well placed. They don't absolutely have to be omni. Of course....you'd need some sort of mixer or AI to get that done. Even a few cheap mics...which you can find easily....might help you. Even cheap mics can perform ok for dialog. Depending on the room acoustics....your results might not be optimal.

[TalismanRich]

You don't say anything about how many people and how big the room is that you are using.

You might try using a boundary mic. The biggest problem is when you have room echos along with various people talking at the same time. This is especially bad if you have a lively room with lots of hard surfaces.

If you can use multiple mics, then good clip on lavaliere mics can improve things a lot. There's a reason why you see clip on mics on nearly every talk show and news broadcast these days.

[Jacknife27]

What equipment (other than the mics) are you using to record with? Audio Interface....PC.....mixer. I think that adding a couple more omni mics would help your cause if they're well placed. They don't absolutely have to be omni. Of course....you'd need some sort of mixer or AI to get that done. Even a few cheap mics...which you can find easily....might help you. Even cheap mics can perform ok for dialog. Depending on the room acoustics....your results might not be optimal.

Hi, currently the available equipment is basically a laptop with USB, but I am not opposed to buying an audio interface if thats better.
Would it be absolutely necessary to buy a mixer or can that be done via software?

The room probably has some echo because the ceiling is about 5 metres high.
Weve tried the Samson CM11B with an audio interface before which produced the mentioned mediocre/bad results, However we need to buy multiple sets of equipment anyway so I can deviate from that.

You don't say anything about how many people and how big the room is that you are using.

You might try using a boundary mic. The biggest problem is when you have room echos along with various people talking at the same time. This is especially bad if you have a lively room with lots of hard surfaces.

If you can use multiple mics, then good clip on lavaliere mics can improve things a lot. There's a reason why you see clip on mics on nearly every talk show and news broadcast these days.

About 20 people

Sorry english is my second language and I actually meant a boundary mic and yes the problems you mentioned occured.
Clip on mics are sadly not an option, too many people.

[mjbphotos]

I'd suggest a USB mixer to get the sound into the computer, as it will at least allow you to plug in multiple mics. The closer mics are to people, the better you will be able to hear them. The USB mixer could eat up half your budget, so not sure how many mics you really could get for what's left.
Sounds like a business problem? "Hey boss, need a larger budget!"
Do the 20 people in the room have laptops? If so, then they can all log into Zoom separately and use mic/camera in their laptops.

[TalismanRich]

Given the limited resources, the best approach may be to try to group people as much as possible, perhaps into 3 groups, use cardioid mics to limit back reflections, and to try to deaden the room as much as possible. You really aren't trying to get maximum fidelity, so if someone is slightly off axis and loses some high frequencies in their voice, it shouldn't hurt too badly.

I've been on conference calls where the subjects are in a 12ft square office with concrete block walls, and quite often it was nearly impossible to follow the conversation. Its a difficult situation. It helped a lot when we could get in a room with an acoustic ceiling and heavy drapes.

[Jacknife27]

I'd suggest a USB mixer to get the sound into the computer, as it will at least allow you to plug in multiple mics. The closer mics are to people, the better you will be able to hear them. The USB mixer could eat up half your budget, so not sure how many mics you really could get for what's left.
Sounds like a business problem? "Hey boss, need a larger budget!"
Do the 20 people in the room have laptops? If so, then they can all log into Zoom separately and use mic/camera in their laptops.

Its definitely too tight of a budget, I will try to get more with the reasoning that I cant find a good solution thats fits the budget.
Most of them dont bring a laptop, but iI will téll one of the guys to have a testrun.

Given the limited resources, the best approach may be to try to group people as much as possible, perhaps into 3 groups, use cardioid mics to limit back reflections, and to try to deaden the room as much as possible. You really aren't trying to get maximum fidelity, so if someone is slightly off axis and loses some high frequencies in their voice, it shouldn't hurt too badly.

I've been on conference calls where the subjects are in a 12ft square office with concrete block walls, and quite often it was nearly impossible to follow the conversation. Its a difficult situation. It helped a lot when we could get in a room with an acoustic ceiling and heavy drapes.

Sadly people ned to sit with 1.5 metres distance because of corona.
God I hope the whole thing gets scrapped altogether.

[ecc83]

Ok, some (many) years ago I had a rather similar problem micing up a chorus line (Gang Show NOT the WE show!) Cash was also in short supply but I bought 5 iirc very cheap "cassette" dynamics, rewired them to balanced operation and suspended them in a line about 1/2 mtr above the highest kid in the line. The cable ran all the way up to the gods into a single channel pre amp (valves and a transformer) and we got decent reinforcement and recording on tape.

I suggest you arrange the people in half circles of five and plonk a mic in the centre, might be as well to point the mic skyward and not at the middle bod? The mics can be the uber cheap Behringer XM8500 bit more sensitive than a '58 and really pretty good sound. £15 here. A 4 inpout mixer would SEEM to be indicated but in fact you could do what I did and splice mics together in parallel twisty-twisty and Gaffer tape will suffice for the duration. Two groups of two? A basic 16bit USB mixer will be fine as the ambient noise floor will be high, all those hearts and lungs! Better than an AI in fact as you can usually apply EQ and a hefty dose of bass cut is a very good idea.

I can do you a rough drawing if you wish?

Dave.

[mjbphotos]

Sadly people ned to sit with 1.5 metres distance because of corona.
God I hope the whole thing gets scrapped altogether.

How long is this zoom meeting? I can't believe your company would even do this - have everyone use their laptops from home/separate offices. Stupid idea to put 20 people in a room right now. Are people wearing masks, too? That makes it even harder to get good sound.
Latest MIT study shows 10 people in a 20'x20' room with no masks having about an 18 minute 'window' to get infected if one person has the virus. Open a window and you buy another 6 minutes. If everyone wears masks, you get about a half hour more.

[ecc83]

How long is this zoom meeting? I can't believe your company would even do this - have everyone use their laptops from home/separate offices. Stupid idea to put 20 people in a room right now. Are people wearing masks, too? That makes it even harder to get good sound.
Latest MIT study shows 10 people in a 20'x20' room with no masks having about an 18 minute 'window' to get infected if one person has the virus. Open a window and you buy another 6 minutes. If everyone wears masks, you get about a half hour more.

Yeah, missed that! And IF they all use their lappys, buy them all a Sennheiser USB headset about $20 KAYlometres better than a room and laptop mic at a metre.


Dave.