Audio quality is important in online music lessons, but how do you achieve it? What affects audio quality in a video conference?
1) A Quality Mic is Not Optional
No video conferencing software or setting can make a laptop, webcam, phone, or tablet mic sound great. Those mics are made for having conversations, not recording or music. Do not expect a webcam mic to sound noticeably better because you changed audio bitrate, codec, or pretty much anything else. Most video conference audio tweaks (including below) will only make a big difference if you are using a quality microphone. Know the differences in mics:
Laptop, Webcam, Phone, & Tablet Mics
Mics built into these devices are designed to pick up speech. They are are almost always low quality, though some are better than others. That said, the most important thing to know is that they are designed and set up to pic up sound within 5-8 feet.
Headset Mics
Headset mics are also designed to pick up speech but only the person using it. In other words, they are setup to pick up close range. Again, these are almost always low quality, especially in-line (on the wire) mics built in to wired ear buds. The main advantage is if the headset positions the mic in front of your face, but again only for speech. Be aware that, if you are using a plug-in headset (3.5mm), your software might not see it as a "device" and you will need to adjust in your computer settings.
USB Mics
A USB mic is the easiest way to improve your sound. They don't require an extra interface, mixer, or other equipment because they convert the analog waveforms to digital before sending it to your computer. USB mics don't rely on your computer's sound card like a headset or other mic you plug in to the 3.5mm jack. Keep in mind, though USB mics are mostly plug-in-play, some have specific windows and or mac drivers that could increase performance. They also have different, "patters" which determine what area (distance and width) they pic up.
External Analog Mics
Analog mics differ from USB in that they send waveforms to the computer (or interface) without digitizing it. Before USB mics came along, external mics plugged in to the 3.5mm mic jack. Today, you can certainly utilize an analog mic. It is best to use a quality mic with an "XLR" connector. Then, use an audio interface which will convert the mic's analog waveforms to digital and send to your computer through USB.
2) Know Your Settings
Many video conferencing platforms contain audio settings which can be tweaked. Usually, these settings are only available if you are using a computer. With Blink Lesson, we include these settings no matter what device you are using. That said, there is no setting that can overcome a poor mic.
Bitrate
Bitrate, in simple terms, refers to the amount of music data is sent per second. The higher the bitrate, the less the audio has to be compressed. Some software (including Blink) will allow you to adjust the audio bitrate. Today, most video conferencing tech is advanced enough to increase the video and audio bitrates based on your bandwidth. The problem is, by default video is prioritized over audio. Thus, if you have high bandwidth AND a quality mic, increasing the audio bit rate can make a big difference.
Noise/Sound Suppression/Cancellation
Video conferencing platforms include noise suppression (canceling) technology which attempts to cancel-out other people's voices which came from it's speakers, and reduce background noise. Without noise suppression, your mic would pick up every sound from your speakers and include it in the audio-stream it sends back to other people in your meeting (e.g. echo).
The problem: suppression alters the audio and takes time to process (though mil-seconds). But, without it on, you MUST where headphones. If you are willing to wear headphones (which is a good idea anyway), some video conferencing platforms (including Blink) will allow you toggle it off.
3) Latency
The term, "latency" is used to refer to different things in tech. In the online music teaching community, the term has come to refer simply to audio being delayed or not lining up in a video conference. The problem is, there are misunderstandings regarding which factors affect this issue.
Audio Latency on the Device
All sound is analog and must be converted to digital. This occurs on your device's (computer, tablet, phone) sound card (or audio interface). Latency can occur during this conversion, particularly if the card or device in general is low on processing power or memory. If your device is running smooth, the latency here will usually not be poor enough to affect a video conference.
Audio Latency from a DAW
Running audio through a DAW in order to add affects (e.g. guitar), can cause latency. With Blink Lessonwe allow up to 3 audio inputs so you can avoid having to use a virtual mixer. In any case, the more software the audio goes through before reaching the internet, the more chance of delay (though it is often negligible).
Latency Due to Wifi
Among the components of your local network, Wifi interference causes the most problems for audio during video calls. Think about when you are driving, listening to the radio and find yourself under power lines or in a tunnel. Those things interfere with the radio waves. Wifi interference can greatly decrease how much (bandwidth) and how fast (latency) data can be sent from the wifi access point to your device.
Netspot provides this excellent article on causes of wifi interference and potential solutions. Essentially, interference causes fall into two categories: Physical aspects of your home/office and other electronics.
A location in your home/office can have zero wifi issues with YouTube, but constant video call problems. The issue is: during a call, audio/video is being created in real-time. Thus, interference in the connection will cause more problems as none of it can be buffered.
Latency in Your Internet Connection
Latency in internet terms (also called ping rate) is a measure of the of time (milliseconds) it takes to send information from one point to another. If we use the analogy of a pipe; bandwidth has to do with how wide it is, and latency has to do with how fast things move through it.
Think about it this way: if you only use your connection to download content, even movies, latency is less important because you are retrieving data that is simply stored on a server. It will take longer to "buffer" the content but eventually it will arrive. With live video calls, the data (audio/video) is being created in real-time and thus cannot be buffered.
You can test your internet latency here. Please note: The connection your ISP provides is usually the cause of poor latency, but your local network and device can also play a role.
Latency in Video Conferencing Software
Video conferencing software itself does not inherently create latency, but it's set up can contribute to the problem. In other words, audio delays and other issues are present because the software is set up for a conversation.
The biggest factor is noise/sound suppression/cancellation. See above for information about this. Some platforms, including Blink Lesson, allow you to toggle this processing off, but all will require the use of headphones.
There are now several music-focused platforms with claims about low latency, and more to come. Can these platforms, or any platform, fix a bad internet connection or wifi interference? No. Instead, they adjust the settings mentioned above out-of-the-box. Some platforms go further but require the purchase of specialized audio interfaces.
Your Expectations are Key
As you can see from this article, audio quality in video conferences, including latency, is complex. Its important to adjust your expectations on the device and connections being used. If you teach private music lessons, you probably don't want students to be required to buy a $200 interface. But, there are small preparations and tweaks you can make to make things better.
At Blink Lesson, we are about making your online music lessons easier and better. We do not make unsubstantiated claims, but we also know our platform allows for a better experience. Get a free account now and see how easy it is to adjust audio settings during a session. We are here to make your entire online teaching experience better
