Will using Shotgun Mics Overcome Imperfect Room Accoustics?

bacardioid

New member
Hola amigos!

We do a variety of things, from a podcast, online webinars (with high quality audio being important) and video voiceovers.

Now, we've got 1 room that is very, very well-treated, and we use our large diameter condenser in there. It's actually the clothes closet in my home! 3 walls full of clothing really soaks up reflections, and a 4" thick hunk of foam on the door (read: mattress my kid grew out of)! This is where I'll do solo stuff like a solo podcast, a voiceover for a video, etc. Never have a problem with reflections, echoes, or anything. The closet is really nice and quiet.


But for everything else, where we have 2-3 people, we HAVE to do it in a business office. The office itself is 12 feet x 12 feet x 10 foot ceilings. Drywall all around. We do have some 2" thick acoustic panels on the 4 walls, but I would say we only have a total of 20%-30% wall coverage at most.

One setup I have been testing for 2 people doing live webinars as well as recorded podcasts is:

  • (2) sE V7 (Cheap Dynamic mic, like a Sure SM58)
  • Signal runs through dbx 286s channel strips to a MixPre-6 recorder.... OR if it's live, through the channel strips directly to the Desktop computer
  • I'm using Reaper as the DAW
  • The basic position of the 2 people is opposing each other, across a table, about 5 feet apart.
  • For live webinars, we use 1 mic because the 2-3 people are sitting next to each other in front of a camera, so no problem there.
  • I am getting what I think is a lot of bleed, and to my untrained ears, it seems like it's room reverberation (because it sounds a little echo-y, but I can't tell if it's an echo, or the mic directly picking up the other person talking from across the table.
  • If it's the room, then I would expect that my first change should be to add more room acoustical treatment, but this is actually my working office, and I can't turn this into a full-time studio :(
  • I have experimented positioning with the sE V7 mics, and trying to get them so one speaker is not speaking directly into the back of the other mic (I am trying to offset them to get the 'other' person out of the sensitive area) but it doesn't help as far as I can tell.

So, if we assume we can't fully treat this room, would switching to shotgun mics be helpful? I've seen some guys on YouTube who use shotgun mics for voiceovers, so I figured it wasn't a 100% dumb idea! :) (just somewhat dumb, hehe)

As far as the office/room, I only have space to add perhaps 4" thick bass traps in 2 out of 4 corners, and MAYBE a couple more 2'x3' acoustic panels on the walls. Since this is my office, the panels are the artwork kind of panels, because I have clients and employees in my office all the time, and I can't have it looking like a studio. Maybe one day I can take one of the extra rooms we have and make it into a good studio, but right now I need to stick to this particular office.


So, long story long, does anyone have any recommendations on using shotgun mics for podcasts? If it's 2 people, we'd be across the table from each other, and I was thinking the shotgun mic would be a super or hyper cardioid, and reject side and rear sounds. If we have 3 people recording, we try to sit in sort of a triangle shape, so we are equidistant from each other.

I have tried watching how really popular podcasts do it, when you watch their YouTube videos. Sometimes they have 5 people in the room and there is no apparent bleed or echo, and they rarely have a fully treated room... They're often using SM7Bs.. is it because they have more SPACE and the mics simply don't pick up extra sounds?

I have experimented with the dbx 286 channel strips, especially with the noise gate, but either it's not enough, or I suck at tweaking it! I also downloaded and tried izotope RX6 with the "de-bleed" feature, and besides taking a long time to Learn and Process the sound, the results were pretty crappy. I could still completely hear the audio bleed from one track into the next.

Keep in mind, I'm using semi-decent headphones when editing, and I can hear the bleeding when I mute a track and isolate the other track. When both tracks are playing, I am not sure an average listener would be able to tell, but I am concerned it would degrade the overall sound quality.

Thank you very much for reading my incredibly long post! Any and all thoughts and advice are very appreciated!!
 
From what I've seen but for quite long shoot guns, their patterns are not a lot tighter than good hyper cardioids.
Reducing the distance to sources are a way more effective route to take from the mic 'wanted-to-unwanted signal ratio goal.
And how about a few stand alone (and 'stowable) gobos to place around the speaking area? There you'd be tackling the other side of the problem -small hard sounding room tone.
 
Super and hyper cardioid mics are problematic because of the bit they pick up from the rear. In the f2f scenario it’s guaranteed to introduce bleed but whether it causes anything annoying would be only determined by testing. Regardless I’d stick with a cardiod pattern.

The bigger problem will be the reflections from the untreated room, and a shotgun won’t help a lot because the worst reflections will come from the opposite wall, and there the shotgun is essentially just a narrower cardiod.

I’d experiment with the mics you have and try some temporary treatment like heavy blankets, etc. behind each speaker to try and evaluate how the mix sounds.

I don’t think you need bass traps for the spoken voice.

With all that, lavaliers would be a lot simpler if they work for you!
 
The best bet would be to just get closer to the mics. If you are doing video, and you don't want to see the mics, use lavaliers.

Shotguns won't help much, unless you are pretty close to the source.
 
Yeah I like that idea especially for live webinars, because everyone else at my office is awkward when it comes to audio gear. (Like... uh there's this MICROPHONE in my face, what so I do?!?!)

Laviers would be the easiest for them!

I'm just wondering about the sound.


I'm used to doing my 'most important' recordings in a clothes closet and get great sound. Lavalieres are known for not sounding as robust right?

(Of course, if this is for the Iive webinars, they would not only be inconspicuous, but the huge compression you get with any internet webinar service would cancel out any advantages of "nicer/better" mics... Like Google Hangouts, GotoMeeting, YouTube Live.. they all compress the video and audio stream to save bandwidth. Don't even get me started on that!!!) :) We've got fiber connections at our office, yet and the best connection we can get from Google Hangouts is 720p.. who knows what the audio does.. hehehe
 
I am thinking more super-cardioid, a shotgun pattern that is lot as long as a full on shotgun.

Another possibility is something like a Sennheiser ME64 (needs a K6 module with it) which is designed for interview and has a tight cardioid pattern. I have several old Sennheiser ME80 / K3U mics that work really well for this kind of thing.

Look at a rode NTG-1, maybe an NTG-4

Alan.
 
I'm surprised nobody leapt in and said that if you go on video forums, everyone continually moans about how dreadful shotguns are indoors, let alone in small rooms.
 
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