"Gas mask" effect?

I’m looking to put an effect similar to speaking through a gas mask on some recorded dialog, something like Psycho Mantis in Metal Gear Solid.

Any ideas how to approach it? I’m guessing that equalization will get me a lot of the way there, but I haven’t found a curve that gives good results. Will I need to run it through a different filter?

Like a pilot with an oygen mask ? … https://forum.audacityteam.org/t/alter-voices-to-sound-like-fighter-pilot-or-space-man/10767/2

The vocoder is probably the closest I’ve gotten to the right sound, but the effect isn’t consistent… it shifts and changes over the course of the recording. It also sounds quite unnatural, which isn’t what I’m aiming for. Maybe there’s a settings combination that mitigates this?

That thread has some good tips for radio/telephone-style equalization, which will be handy, but it’s not the right sound for this.

You’ve linked to a three hour video (!), I didn’t know Youtube videos could be that long.

For those who don’t have 3 hours to spare here’s a sample of the chap …

It’s a bit like Darth Vader, which is a comb* effect , (they’ve added the same inhalation sample to the end of every sentence).

[* free audacity comb effect on this page … http://audacityteam.org/download/nyquistplugins ]

That’s the one! Thank you very much. If I play around with equalization a bit on top of that, I’m sure I’ll get the right sound.

You’ve linked to a three hour video (!), I didn’t know Youtube videos could be that long.

For those who don’t have 3 hours to spare here’s a sample of the chap …

I deep-linked it to the relevant part. Sorry if it didn’t work for some reason.

Nearest I can get at short notice is an astronaut helmet effect …

Remove all frequencies below 300Hz (using equalizer).
Apply David Sky’s comb filter: frequency 444Hz, decay 0.04
Then leveller on “light”, ( leveller is in Audacity’s effect menu ).

The “Leveller” effect is now one of the distortion types in the Distortion effect (Distortion - Audacity Manual)