Recording & Streaming your event – Audio 2/7

This is the second article on the “Recording and Streaming your event”.
In this post, I cover details of the Audio recording.

Table of content of the series:


Audio

Fifine K031b

Fifine K031b

For PSConfAsia (since 2017) we’ve used another type of microphone as audio input: the Fifine Wireless Lavalier Microphone, K031B (~£44/$40), pictured above.

Wireless Lapel / Lavalier Microphone with USB Receiver

The main benefits is that it’s a very decent, very affordable lapel microphone on UHF (not Bluetooth, longer range, with frequency management), where the receiver directly plugs into the USB port of your computer running your capture/streaming software (no battery needed for receiver).

The benefit of using a lapel (or lavalier) microphone is that it’s near the source (speaker’s mouth), and easily blocks ambient noise (AC, Fans, room with poor sound characteristics, audience and so on…). You will achieve much better result than from the WebCam’s audio, or a boom microphone, unless it’s placed about 40 cm from the subject (some speakers move a fair bit, don’t they, Rob?).

We’ve not used a head-worn mic, only the clip-on, because Fifine did not include them back when the PSConfAsia folks bought them. In theory, that could be better because no matter how much a speaker turns his head, the volume should not change. That said, I’ve also done the mistake of clipping the mic too high, or too much on a side (i.e. on a Polo shirt’s collar). The problem with head-worn mic is that it’s so close to the mouth, it’s much more sensitive to plosives, and clipping. I’ll probably stick to clip-on, 15 to 20 cm down from the mouth, until I’ve experimented enough with head-worn ones.

With that USB receiver, the microphone is recognised as such by your OS and can easily be mixed in your software. You’ll adjust the gain (amplification) in software, and you don’t have to worry about mixing, mono/stereo and so on if you use only one.

But the fact that it’s the simplest way to capture the speakers’ voice, is also one of the caveats. The microphone is there only for capture, and if the room is big and requires the speakers’ voice to go through a Public Address system (PA, comprised of Mic, Amp, loudspeaker and usually mixer), it’s another can of worm. Those USB receivers have a monitor/headphone out, but that can be challenging to run through the PA system.

Public Announcement (or Public address) Systems & Audio in Conference Venues

PA System components

PA System components

I’ve done just enough events to know that no two venues are the same. It sounds obvious, but actually makes capturing a decent audio a real challenge.

If the room is small enough, then you should be fine without relying on a PA system, and only use your Lapel mic for the recording. The speaker’s voice won’t be amplified, but hopefully it will be enough for your audience. The room configuration really makes a difference: a room relatively wide but relatively short in length can be OK without a PA System, but a deep and narrow room will be challenging. People at the back may struggle to ear clearly (and probably see the screen).

In my experience, I’d say that in average you can have a room up to 60 people without PA system. Depending of the configuration, shape and treatment (i.e. absorbing panels), it can probably go up, but it might not be comfortable for some speakers or the audience.
Remember this, and be nice to your speakers!

Most venues with rooms above this capacity will provide wireless microphones and a PA system, sometimes as an extra, and for a steep price.

Technically, the main two types of room are the “Professional venues” or the “Corporate Conference Meeting rooms”. I put the quotes here, because that’s my own classification, based on my limited experience.

Professional and permanent venues are usually equipped with professional equipment such as top quality Microphones you won’t even find on Amazon. Sennheiser, Shure, Audio Technika and the like, with price for a 2 mic + 1 dual channel receiver probably well above £500/$550, like the Sennheiser EW 100 G4-ME2. The audio from those device is great, but the setup more complicated for non-professional recording and you’ll need extra equipment.

Mixing Board

Mixing Board

They usually connect the receiver to a mixing board that can be at the back of the room, or a mixing room/space on a balcony or in the centre. If you want to use this audio as input, you’ll have to connect somehow to the mixing board. I’ll explain the plugs & how to do that later, but the main issue will be that the location where the audio is available, might be far from the speaker (and where the HDMI feed for the screen capture is). Purpose-built venues usually have some cables running in walls, floors or ceiling, and one or more panels to connect to in the room. Those may still be far from the speaker which is unpractical when you get the HDMI feed from there!

This is the kind of questions that are quite hard to find out before the conference unless you visit the venue. The main reason is that you usually have many people in the middle of the communication you’re trying to have, who don’t understand what you’re trying to achieve and how. It’s tough to get the info between the conference organiser who’s got a zillion other worries, the sales person of the venue, and the AV technician who may have never seen a guy trying to record all audio, screen and picture mixed together on the fly with amateur equipment. Fun times!

Corporate Conference Meeting rooms are the auditoriums, Multi-purpose rooms, big meeting rooms and big rooms with other names but similar purposes. The main point here is that they target a different type of usage, usually focusing on providing a venue for an internal event where, at best, the event will be streamed/recorded for the employees but with a live audience. Similar to meeting rooms, they usually are all-in-one solutions, where everything is included in a default package, but are not modular or extensible so that external companies can come and plug equipment.

Most of the times (in my experience), they have a good PA system, but without input or output you can tap into, or you feed into, to use your own microphone. They sometimes have a camera integrated to the system, but you can’t use it because it’s only configured on their system and you can’t get a NDI feed (Network Device Interface). Also, those rooms often have the cabling “built-in”, without in or out panels, and configured in another room so far away that it’s not possible to even think about grabbing a signal and running a cable.

In short, either the speaker doesn’t need voice amplification, and you just wire him to your recording mic, or you put two microphone on the speaker: one for the PA system, one for Recording. Definitely not ideal, but that’s often the best and easiest way.

Modularity and portability for audio (advanced setup)

A big factor in the equipment I consider is how transportable and modular it is, because I usually fly to the conference I help record and stream. The maximum form factor for the equipment I bring is what fits in a Pelican Air 1535 case (£240/$200), because that’s the biggest carry-on Pelican case. This is related to the audio part because that’s what influenced me in my next decision.

The Fifine microphone I explained above is great, but it did not provide enough modularity and flexibility for me. I wanted greater flexibility with the system I was using:
– a way to allow and mix two microphones for sessions with two speakers,
– tweak the gain individually for each microphone
– record the audio before it gets to the PC (a plan B, because we had issues)
– Provide multiple output so that I could monitor, and send to the PC for recording and on a PA system
– and other use cases not related to streaming or recording presentations (field recorder for interviews)

Fifine K037b

Fifine K037b

I bought two Fifine Lapel Microphones K037B (note the difference from K031b), which are very similar but have a battery powered receiver with a mono Jack 1/4 (aka 6.35mm).

Now I needed to mix the two microphones in one stereo track for output, record, and amplify. I also wanted to be able to accept balanced XLR inputs with phantom power for when I’m in a professional venue. So I bought a TASCAM DR60d-mkii, which has two combo XLR/Jack 1/4 inputs, a great amp, and several outputs. The only thing missing was an Audio USB interface to use this as input in OBS.

I know you can do some mixing in software, but I find myself adjusting the gain from a Mic many times in a session to provide the best experience. Sometimes a speaker gets passionate, or talks to someone else and you don’t want that to be on the recording nor remove in post processing, so a knob to turn can be easier than a software GUI.

TASCAM DR60d-mkII

TASCAM DR60d-mkII

To interface the TASCAM to the PC, I bought the Griffin iMic, an USB audio input device (since then, deprecated I think). It’s tiny, light and works (enough). Sometimes (once every couple of days of usage), the sound is awful and you need to unplug and plug it back to fix, which means you may need to reconfigure your software (a bit). The internal gain is really noisy, and sensible to your USB Power, but the TASCAM was doing the heavy lifting.

The combination TASCAM & iMic is fantastic for modularity and mobility, can provide good sound quality, but takes a bit of time to get used to, and find the right settings for low noise (in short, test your cables, and let the TASCAM do all the work). As the TASCAM can record the inputs at the same time, it’s a perfect backup plan, but I try to avoid the need because I don’t want any post-processing.

iMic being discontinued, you’d need to find another Audio to USB input, and there are many on Amazon or ebay, relatively cheap, but would need to be tested.

In future

Behringer UMC204HD

Behringer UMC204HD

The TASCAM and iMic have served me well, and I’ll still use them in some cases. But when you’re in a purpose-built room, you may want to have the fewer hops possible to your AV mixer.

To provide a more direct input to PC, while keeping the dual channel, jack/XLR combo, I’ve recently bought a Behringer UMC204HD (when the room requires two channels or more), and a Behringer UM2 for single channel work (I want to own equipment for ~3 rooms/tracks). I’ve just started testing with them, and don’t have an opinion yet, but on paper, they seem good. The UMC is a bit more bulky and heavy, but seems sturdy. UM2 is plastic and seems not as good, but is lighter.

It’s worth noting that whenever you want to grab the audio from the PA system or whatever the venue offers, you should use an XLR cable if possible. The XLR is a special connector & cable, shielded, and built to also carry “phantom” power of 48v when needed for, say, a condenser microphone. The main characteristic we’re interested in, is that a balanced audio cable is much better at carrying sound without picking up electromagnetic noise, especially compared to a 1/4 Jack and standard cable.

The two Combo inputs on the left of the UMC204HD can both accept either a XLR or a Jack 1/4″ connector, same goes for the the inputs 1 and 2 on the TASCAM DR60d MKII.

Fifine K038

Fifine K038

For the microphone, I’m looking at the Fifine K038 because it has a few things that could complement or replace my two K037 (and I should probably have bought that in the first place):
– it’s a main-powered receiver (no more loss because the receiver ran out of battery, sorry Prateek)
– it allows up to 4 input by plugging the K037 to the optional mic inputs B and D
– it is compatible in frequency, so my existing emitters could work with one of the channel of this receiver

This should allow to have up to 4 speakers in a panel session, or more if I was to chain several units.

I should probably add that I don’t hold any share in Fifine, nor that they’re the best I’ve ever seen. Just that they’re very good value for tiny budgets, and once you start with 1 brand, keeping with the same allows you to mix and match Transmitters & Receivers as you need them, or ripping one apart to get some spare parts for another.

To summarise, the plan with the UMC204HD is to either use it to pick up the mix from the venue and their microphones, or to do the mix and capture my own microphones, while sending that to the venue’s PA system. Same idea for the UM2 but for only 1 microphone.

 

NEXT: Screen Capture

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