Krisp installs on your computer, creates a “virtual” microphone of the same name in the system and tries to remove background noise during your Zoom calls. You can find all the details on the app’s website: krisp.ai (my referral link).
I didn’t run the tests for the referrals, but since I’ve written the post anyway, why not add one :)
I wanted to see how Krisp would work in my use case: a video call from a MacBook with AirPods in a noisy café. I emulated the café with various recordings from SoundCloud, played through the speakers of my home audio system. I recorded the sound in Loom, a screencast app. Zoom might behave differently, but it’s unlikely.
I’m happy with the result and will try it “in the field”. Given that there’s now a free plan with 120 minutes a month, you can keep the app on your computer for calls from noisy places. In some cases it spoils the quality of the voice, boosts the highs and distorts it. But in return it removes background noise excellently and copes so-so with a voice nearby.
In everyday use, for the other person to understand me well, it’s better that my voice sounds worse but there are no distracting voices or noise in the background.
That way the other person can turn up my voice and adjust, but they don’t have to “filter out” other sounds in their head. In my subjective experience, voices are the hardest thing to filter out in your head.
The second use case I want to test later is a call center, for its operators. I’m 90% sure it’ll be worse there, since the noise is mostly high-pitched and uneven: the neighbors’ voices. Most likely, for operators the app won’t justify its price.
A note on AirPods. AirPods Pro didn’t always connect properly with Krisp and Loom together. I had to disconnect them from the laptop and then connect them again. The ToothFairy app puts the device’s icon in the menu bar and makes this easier.
So, on to the tests.
Variant 1.1: loud music + English-language show nearby + mic hanging loose, without Krisp
https://www.loom.com/share/a5ad779f5f4b4bddb7f5809f98675545
Variant 1.2: loud music + English-language show nearby + mic hanging loose, with Krisp
https://www.loom.com/share/72b51478947d431d94de7441c760a59c
Result: the volume is almost the same and the voice a little lower. The music is almost gone. The voice in the background stayed; it got quieter, but it’s unpleasantly distorted.
Score: 7/10
Variant 2.1: instrumental music, no voices in the background + mic hanging loose, without Krisp
https://www.loom.com/share/86ba4d083e474e5ebbe1b3633196c944
Variant 2.2: instrumental music, no voices in the background + mic hanging loose, with Krisp
https://www.loom.com/share/87fa79d204174e9ea0880b2b0f7196b9
Result: the voice gets distorted. You can feel Krisp raising its volume, and sometimes the highs grate on the ear. The music comes through in snatches, but much quieter.
Score: 5/10
Variant 3.1: without Krisp
https://www.loom.com/share/144e9f7cbb26429393117800935ec9ab
Variant 3.2: with Krisp (I forgot to raise the mic to my mouth)
https://www.loom.com/share/83be7536bc8048039db8b82dee6541c1
Variant 4.1: without Krisp
https://www.loom.com/share/4754b6aa84ca487fbfd45ba42793c542
Variant 4.2: with Krisp
https://www.loom.com/share/5fefbe659e4748e280f50d8cc60de198
Result: for everyday use it’s better not to hear someone else’s voice in the background and to hear me quieter and distorted, than to hear me well with a voice getting in the way. The AirPods’ own noise suppression is better than the wired AKGs’. The voice is quieter, but you hear less of the background music even without Krisp.
Score: 7/10
Variant 5.1: without Krisp
https://www.loom.com/share/edee5659a97645ca828111087bb3b056
Variant 5.2: with Krisp
https://www.loom.com/share/272e37ae5aec4ceab83eb8ebe7fae03e
Result: holy crap! It’s quieter, but the café noise is cut out completely! Completely!
Score: 9/10
Variant 6.1: without Krisp
https://www.loom.com/share/3912d910ec084fa49fdbb60b28b0873c
Variant 6.2: with Krisp
https://www.loom.com/share/b11beff89ed94dcbb27d0576e6e0baf7
Result: it picks up the “neighbor’s” voice, and it distorted my voice a lot. You could call this the limit of usability. Sitting in such a noisy place is unpleasant in itself, so it’s not quite the everyday use case I wanted to test. Let’s bring the noise down to something more usual.
Score: 3/10
Variant 7.1: without Krisp
https://www.loom.com/share/ca878d87226e4f548faf4e1591351c8c
Variant 7.2: with Krisp
https://www.loom.com/share/33e8724667cc42d29fe48d7fe111f53b
Result: a little of the voice is there, and overall the noise suppression is less noticeable. So it works best when the café is very noisy but there are few highs (nobody close by). In conditions like these Krisp makes less sense, but it still makes some. I can hardly hear the “neighbor” and can’t hear the ambient noise at all.
Score: 8/10
How I measured the noise level in the room. I used the Sound Meter app from the Android app store. I think any similar app will do if you want to repeat this.