Shock mount for use in a restaurant

I love Audacity. I’m a newbie to sound recording, and I’m learning so much by experimenting with the settings.

Now for my Q. I’ve got a Blue Yeti linked to an HP core I5 notebook running Win 10, and I want to record interviews and my comments in McDonalds restaurants. I can cut out most of the music and background noise by using the cardioid setting, but I’m still picking up a small amount of interference, and also some vibration from the table. The Yeti had got a really solid stand, and I think this is transferring some of the noise. Obviously I can’t use a boom with a shock mount, so I wondered if I could make a base to stop the transfer of vibrations. Would something as simple as a polystyrene board make much difference?

Or a little something from Houghton-Mifflin and Wamsutta.

It’s soft and gooshy on the bottom and stiff/hard/heavy on top.

Here’s a more customized version. That’s 3/8" plywood on the top, high-heat black spray paint and Duveytine (theatrical black felt) on the bottom.

Koz

You can transfer vibrations up the cable, too. So no tight-stiff pathways to the laptop. This is where USB microphones can be a problem.

Koz

Sorry. That’s 1/2" plywood (12.5 mm). I went out and measured it. That looks far cooler than the novel and towel, it doesn’t work quite as well. If you have woodworking tools, you can go nuts. Round the corners or bevel the edges for a nice Queen-Ann look. I use furniture-grade plywood so I don’t have to worry about one surface.

Koz

Thanks for the replies.
The USB cable that came with the device is nice and long, so no tension there. :slight_smile:
I tried polystyrene, and it’s rubbish. I got better results using the cardboard box. :slight_smile:

The wood and felt looks like the best option. I’ve got a solid wooden chopping board that I could use. Would thast work, or is it better to use ply, perhaps because of the grain crossing in the layers? I’ll try to find some thick felt to go underneath.

In Koz’s “towel and book” example, the towel absorbs high frequency vibration, and the mass (weight) of the heavy book resists low frequency vibration.
A similar solution that I’ve seen work very well was a couple of layers of “camping mat” foam (high density foam) with a small 2cm thick concrete garden tile on top. then the mic stand on top of the tile and the mic held in a “spider” (Shock mount - Wikipedia). This was very effective even though the building was next to a very busy 6 lane road above an underground railway (North London, England).

I got better results using the cardboard box.

You need two “things.” Soft/fluffy followed by hard/unyielding. Set up the book and towel and use that as the goal. You could be a long time flipping between trashy solutions trying to find the magic one, particularly if you’re trying to do it with one “thing” instead of two.

The Yeti doesn’t weigh anything, so it doesn’t enter into the design. Whatever you put between the towel and the Yeti needs to be heavy…or heavier.

chopping block

I don’t think it matters if it’s solid or laminate. This isn’t that kind of solution. Heavy is good. Stick that on a towel and try it.

Koz

I’m really grateful for the advice, and I think I’m starting to understand the dynamics here.

I’m going to try the chopping block if I can get it away from my partner. :slight_smile: A towel seems to be a good start for the experiment, and somewhere I’ve got an old felt typewriter mat, but I’m not sure if it didn’t get thrown out when I moved. I take the point about soft and fluffy. It doesn’t have to be perfect. The two main uses are to record a series of interviews with an old farmer, and that is a different problem. The noise reduction is required for my voice overs for videos on a virtual museum site that I hope to build.

Exactly correct. Once you know what the noise is thinking about, you can take steps.

Most vibration suppression works like this. This is an AKG system.

The circular thing is a bunch of rubber bands. That’s the soft and gushy part. The microphone itself is metal and heavy so that’s the stiff/heavy part. I can look it up again, but I believe that microphone is registered as a non-lethal weapon by the State of California. Anyway, that’s the hero combination.

The Yeti doesn’t weigh anything, so you have to provide both halves.

And there are tests you can do. The microphone mount should be “sloppy.” You should be able to push on the mount and it should move a little. Doesn’t have to be much, but if it doesn’t move, then it’s still connected to the table.

It’s not recommended, but if I thump that AKG microphone, it will move back and forth like a bobble-head doll. Also note, the cable is a graceful curve.

Koz

I’m visualizing you stepping into a McDonalds with a camping pad, 18" chopping block and an R2D2 thing with wires on it. I would have a really hard time talking you out of it, because I expect that to work.

The news people have a thing where they have to take care not to become the news event.

Koz

That gives me an idea. I’ve got some industrial carpet that I was given to cut down on condensation in the van. If I cut off a piece of that, then I could use that for the movement part. I guess that placing it upside down under the chopping board would be the best option.

I dfon’t know why you guys keep saying the Yeti is light - it seems heavy to me :slight_smile: but I guess I’m used to cheap domestic mikes.

That gives me an idea.

[Shifting to McGyver mode]

Oddly, this isn’t a help desk, it’s a forum. Posters helping posters. So when you get one to work, post back what you did. Include one of the publicity photos from the shoot. You are doing publicity photos, right?

Koz

I don’t mind being the news event - in fact it would suit me if I did become one.

It’s all part of my project about computing for people on the move. This includes banking, Bitcoin, web site creation, video production and editing, and 'phone communications.

I’ve got quite a sertup when I bring everything in. An HP core i5 notebook, a chromebook, a stills camera, a video camera, a Canon inkjet printer, and now the Yeti. It costs me a lot in coffee to be allowed to set all this up. :slight_smile: When I know a bit more, I’ll put together a video and post it here.

I’ll dig out the chopping block, and do a bit of experimenting tomorrow morning. I have to come here at about 5am when it isn’t too busy, as I don’t want to tie up a table that could be used by a family spending lots of money. It will also be interesting to see if I can use the bi-directional setting to record an interview without too much interference from the music. I might have to ask you guys how I can filter that at the time of recording.

I might have to ask you guys how I can filter that at the time of recording.

We we might have to tell you, you don’t. Audacity has no provision for filters or effects during recording.

to record an interview without too much interference from the music.

You picked the killer problem. There’s no way to suck elevator music out of the show, either in real time or post production. I was happy with the fuzzy-warm problems I can actually fix. In fact cell-phones do this semi-successfully all the time. That’s why they sound like honky-wishy cellphones

If somebody had a gun and said I had to record this, I’d be using two lavalier microphones and a tiny mixer. Still, it would never sound like anything more than somebody trying to shoot a production inside a MacDonalds.

Yes, that’s a Shure FP33 three-channel mixer. As old as it is, they’re till going for $1500 At B&H PhotoVideo. You can make one look like that by shooting voice on racing Cigarette boat in salt-water Biscayne Bay in Florida. We left simple and cheap behind a while ago.

Totally try the bidirectional mode of the Yeti. That’s precisely what it’s supposed to do. If you pleased the sound gods, the microphone’s front and back process will help you kill the music. Definitely write back about that one.

Koz

I’ve no problems posting the results of my experiments. I’ve learnt a lot during the short time I have been a member of this forum.
I’m not doing things for publicity, but to help a number of people, and to preserve some of the knowledge about England’s past.

McDonalds provide a table with two bench seats, free WiFi, 2 power sockets, and 2 USB charging sockets. They are fairly tolerant as long as you are buying coffee and the odd wrap.
I decided it would be an interesting project to produce videos without using a home base, and so far it has been interesting as well as challenging. The audio part is far more complex than I expected. Obviously McD isn’t going to turn off the music, or fit silencers to some of the kids. :slight_smile:

ps. The coffee is really quite good, and half the price of Starbucks. :slight_smile:

Here is an apparently drunk Blue Yeti standing on the chopping board. I managed to get freehold possession of it, so it will become a part of my kit if it works.
I tried the “sloppy” test as suggested with the carpet, and it failed. So I think I’ll have to use either a deep pile carpet, or maybe a cushion. Once I can see some improvements, I’ll post the details.

Someone described the last revision of MacDonald’s coffee as “better than it’s supposed to be.”

The block seems perfect. You do need to worry about having it so big someone knocks into it during the performance.

So I think I’ll have to use either a deep pile carpet, or maybe a cushion.

Or maybe a towel…

A towel is just about the most massively useful thing any interstellar Hitchhiker can carry.

Koz

The audio part is far more complex than I expected.

Sound without the picture is a radio show. Picture without the sound is a rehearsal.

I wish I’d kept it, but I once saw a presentation where someone mocked up a full television news set. It was so well done it was disorienting the first time you saw it. And it continued disorienting until one of the performers started talking. Then it instantly turned into two nine-year-olds in a basement.

Koz

I’ve got a couple of radio domain names, so maybe I should try to start a radio site. I’m trying to do too many things at the moment, so I’d better stay focused.
I’m not sure why I’m resistant to the use of a towel. I can understand the physics, and I can see that it is probably a really good solution. It’s convenient to transport as well. I guess it’s just the aesthetics. I’m probably being stupid, so I’ll sort through the towels and find something suitable.

I noted the suggestion in a previous reply that I use black high temperature paint on the wood. Is that an acoustic consideration, or was it just to protect the wood?

of course you can dry yourself off with it if it still seems to be clean enough.

black high temperature paint on the wood.

That’s correct. That helps a little with visual presentation and microphone fright. Turns out Engine Block or Cooking Grill black paint is far more robust than generic “flat black.” Even if you forgo the heat annealing step (annealing not recommended on wood), the paint job should hold up to building and tearing down a recording session.

My engineering brain will not allow me to paint the cutting block. That’s the end of the world for food. You’ll never get the paint off again.

I know this seems fantasy, but the goal is an interview where nobody can figure out what you’re doing. Relax. Just speak normally into this imposing, scary microphone and pile of colored wires.

This is a holdover from a conference room communications and recording system I helped design. The object is the recording system to vanish in normal use. This one is semi-permanent, not something you knock down at the end of the day. The plywood is 30" (.9M) on the side and sits in the middle of the table. The “towel” is multiple sheets of theatrical felt (Hollywood “Duvetyne”).

I do have a picture…some…where.

Being obsessive, I figured out a way to overdo it. Every so often, I would come into a room and find conference documents and papers piled on top of the microphone (which was still working). Maybe a little too unobtrusive.

This whole conference system wouldn’t work for you. I had a quiet conference room, not “Would you like fries with that.”

Koz