Instructor audio

Audio quality, and balance between instructors, is absolutely critical to good online work, especially teaching. Consider the following:

Checklist

  • Can you adjust your microphone volume from very low to higher-than-needed? Make sure your dynamic range is larger than “barely working”, so that you have some room to adjust for later.

  • Do you have a high-quality headset? A headset with microphone is the most reliable, but if you can get a desktop setup working well, that can be good too. Always have a high-quality headset for backup anyway.

    • If you don’t, and are employed to do CodeRefinery teaching, ask your employer to provide you a headset meeting these criteria.

  • If you have a bluetooth headset, consider:

    • Bluetooth headsets have significant latency compared to wired or purpose-built wireless protocols like gaming headsets have.

    • The microphone might not have enough bandwidth (if it’s part of the same headset).

    • Bluetooth 5 is much better in both latency and quality.

    • Consider investing (or getting your work to invest in) some high-quality headset or desktop audio gear.

    • Recommendation: Don’t use a bluetooth headset. Tell your employer you need something for meetings.

  • “Ducking” is when the first words are silenced/quieted by noise cancellation, until it detects speaking. To avoid this, don’t use “high” noise cancellation (as low as possible is better, reduce environmental noise / use headset mic instead). If you need high cancellation because of background noise, switch to your headset.

  • Set your microphone’s hardware volume to something relatively high - and control via the software.

Latency tester

You can use this web app latency tester https://nullvoxpopuli.github.io/latency-tester/ to check your headset’s latency.

  • Use the tester. Try to click the button in sync with the beats. You’ll be delayed in the first few beats, but will soon sync up and after 10 beats you’ll get an accurate reading.

  • Target values

    • A good value for wired headphones is less than 50ms (it can be within the margin of error of zero!).

    • A good value for low-latency wireless (dedicated dongle) is 100-200ms

  • Other example values

    • 1000-1500ms: The 100-200ms headphones also have a high-quality, high-latency mode when the microphone is not being captured. The latency is over one second.

  • Just consider the difference now, between having a discussion with someone and having 1.5s round-trip latency between compared to 200ms round-trip latency (adding some for Zoom latency - which can be quite small on good connections).