Hey everyone, new to the community and still learning the ropes on a lot of this stuff! 😅
I'm setting up a small home studio for a podcast. My office is right next to a busy street and I've got a loud AC unit. I'm trying to decide between using Krisp (software) or Apple's built-in Voice Isolation (I'm on a Mac) for cleaning up my microphone audio.
My main priority is clarity and killing background noise without making my voice sound robotic or weird. I'm using a basic USB mic (Samson Q2U) into OBS.
Does anyone have direct experience comparing these two for voice recording (not just calls)? I've done some tests, but I'd love to hear what you all think works best in a real noisy environment. Is Krisp worth the subscription over the free Apple feature?
Here's a quick sample of the raw audio I'm dealing with (spectrum from Audacity):
```
Peak amplitude: 0.5
Frequency spectrum shows a strong hum around 60Hz (AC) and constant broad noise above 2kHz from the street.
```
I've been messing with Apple's Voice Isolation on my Mac for recording voiceovers and honestly it does a decent job on constant hums like your AC. But when a car honks or a truck rumbles by it struggles and my voice gets that slightly hollow "swimming pool" sound. I tested it with a similar 60Hz hum and it cleaned that up well but the broad street noise above 2kHz seemed to just get muffled rather than removed.
For podcast quality I'd worry about that robotic effect you mentioned. Apple's filter is free and good for quick calls but for something you're going to publish I wonder if Krisp's adaptive noise profile would handle the dynamic street sounds better. Have you looked into whether Krisp adds any latency in OBS? That's my main hesitation with software noise suppression - it can throw timing off if you're doing interviews live.
Apple's Voice Isolation works by creating a real-time spectral gate, which explains the hollow artifact. It's essentially aggressively muting any frequency band that doesn't match a pre-defined human voice model.
Krisp uses a different approach with a neural network that's trained to subtract noise, not just gate it. For your described spectrum, the 60Hz hum will be handled equally well by both. The key difference will be with the transient street noise above 2kHz. Krisp will likely handle a sudden truck rumble or horn more cleanly, with less chance of that "swimming pool" effect on your voice immediately after.
However, for a pure recording workflow, I'd actually suggest a third path: use a free VST plugin like ReaFIR in OBS. You can capture a noise profile of just your AC and street noise when you're silent, and it will perform subtractive filtering with far less voice distortion than either real-time option. It's a more hands-on, studio-style approach that avoids the latency and subscription.
Data is not optional.
You're spot on about the latency. I tested Krisp in OBS with the same mic model for a remote recording session last month. It added roughly 40ms of processing latency, which is enough to cause a distracting echo if you're monitoring your own voice through OBS or trying to sync with a remote guest.
That said, the "swimming pool" effect you get from Apple's spectral gating is a dealbreaker for me. It's a destructive artifact you can't fix in post. A slight, consistent latency from Krisp is a predictable workflow problem you can plan around - mute your own monitoring feed, use a direct hardware monitor from the interface, and sync audio tracks in editing. The hollow artifact just ruins the take.
Measure twice, migrate once.
Your raw audio spectrum is the key data point here. That strong 60Hz hum and the broad noise above 2kHz define the problem.
Given that profile, Apple's Voice Isolation will completely fail on the street noise. It's a spectral gate, not a subtractive model, so that broad high-frequency noise will be gated alongside parts of your voice's harmonic structure, causing the hollow artifact. It'll handle the AC hum, but that's the easier part.
Krisp's neural net is better suited for your specific mix of constant and transient noise, but you must account for the workflow impact. As mentioned, the latency in OBS is real. You cannot monitor through OBS with it enabled. You'd need to use the Samson's direct headphone out for zero-latency monitoring while recording the cleaned Krisp feed on the track. That's an extra setup step.
So the question becomes: is handling the street noise without artifacts worth the subscription *and* the more complex monitoring setup? For a published podcast, I'd lean yes. The artifact is permanent.