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Comment by vouaobrasil | Hacker News Reader

To push it to the limit I recorded exactly the same recording with my phone microphone and my AT875R XLR shotgun. I did this because my phone microphone is poor and picks up a lot of echo. Results are as follows:

- If the microphone quality itself is bad, the enhanced audio is still pretty horrible. - It does clean up echo but with there's some pretty aggressive EQ that doesn't sound nice, and the noise gate is pretty severe - Compared to my XLR shotgun, the quality of the phone was pretty horrible

What we can conclude is that if you already have a good recording but with some problems, you might be able to use this to remove those problems. However, don't expect a crappy microphone to turn into a good microphone, or a crappy recording to turn into "studio quality".

The bottom line is that there's no substitute for a decent microphone in a decent space. (At the very minimum, small room without echo.)

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This is just beginning.

Look at all the money that's been going into making phones compelling substitutes for professional cameras. And camera tech is still evolving. Consumer audio devices will get the same attention and investment.

We'll eventually have models for audio signals in all sorts of distorted and noisy environments. I'd bet that in ten years a cellphone microphone can duplicate a professional audio setup in 90% of circumstances.

Out of curiosity what phone do you have?

OP should clean both microphones on their phone, usually a sewing needle or thin toothpick can do the trick, but 99% Isopropyl on a toothbrush might be needed afterwards if the grill inside that protects the microphone is also clogged up.

Both microphones need to be cleaned of any blockages so the hardware echo and noise cancellation on a given phone works well. Otherwise you've got distorted audio getting processed as if it's not distorted...

Important question because a microphone array (which exists on some phones, and things like home voice assistants) can be steered into the equivalent of a shotgun mic's pattern, or even more focused than that. It's just that an algorithm aims it toward the strongest signal, instead of the user aiming a hypercardioid mic manually. Either way, this is what reduces the ratio of reverberant room sound ("echo").

> At the very minimum, small room without echo

Why small room? Does that reduce echo?

In theory, would a gigantic room that was miles to the nearest wall be even better?

>In theory, would a gigantic room that was miles to the nearest wall be even better?

Yes, as effectively it's open space. In practice though, to record in high quality you would rather build an anechoic environment, as small as possible (preferably a booth).

Small spaces bring hard surfaces closer to the mic, making flutter echoes and room mode resonances louder, create murky-sounding bass pooling, and can be overly-sensitive to mic position within the space; you can sound oddly different without warning.

You need to absorb the sound of your voice so there is less echo by baffling material on the back of the mic, and absorb room tone and echoes in the area the directional microphone is pointed, generally behind your head. Small spaces have only disadvantages as studios.

To take advantage of a reach-in closet full of clothes, put some pillows on the shelf over the clothes, take the closet doors off, and back into the closet as much as you can. In this way the microphone is primarily listening to the baffled sound inside the closet, and you can avoid bass pooling by speaking into the room—ideally with baffling material (e.g. see http://PillowFortStudios.com/ ) ON the back of a LDC microphone.

"as small as possible (preferably a booth)."

This is where the Startup Garage analogous cliche for musicians comes from: recorded in the closet

Sound takes lesser time to travel in smaller rooms, hence the difference in time is not very large between the original sound wave and the reflected one which makes it harder to distinguish to human ears.

Beware of the wind in such a room

(and of the rain too)

> don't expect a crappy microphone to turn into a good microphone

It's the same as with photos. If your raw material is bad, no tool on earth can make it good.

The tools can make stuff up and produce something, may I say "good", from it, but it won't be the same contents :)

StableDiffusion+img2img may beg to differ :)

How about running it several times, will that make it better or worse?

That could be a fun exercise, I'd imagine you might end up with something like "I Am Sitting In A Room" [0][1]

[0] https://en.wikipedia.org/wiki/I_Am_Sitting_in_a_Room [1] https://www.youtube.com/watch?v=fAxHlLK3Oyk

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