If you open your favorite youtube channels and change the speed to 0.75, that will sound garbage.
The alternative is to turn off this default effect, and can be done inside the browsers developer tools.
Or, you can install the extension global speex to flip that bit for you.
This extension is one of VERY FEW that allow turning off this default effect, usually called time-stretching, but for the web, this feature, standardized by Mozilla is called
.pitchPreserves = true
And there doesn’t seem to be a website in existance that has this set to false.
It works on ALL websites I have been too, except the premium-half-hour trial mode of Pandora and I assume paid accounts. Only radio mode exposes the sound in a clear way that can be modified.
So why do this? We have heard some of the world’s greatest music ever recorded, but it is usually at the same speed and similar experience. So try slowing down one of your absolute top 10 favorite songs by just 4 or 5 percent but keep time-stretching on, and then try with it off. With mild changes it is fine, but around the 90-92% mark I can clearly hear the choppy robotic sound of this effect. Some people or most people may not be bothered by it at that level, but try 0.80 and 75, just as on podcasts or online video, it sounds absolutely horrible.
Audacity for changing tempo, without the choppy sound
If you cannot adjust to the lowered pitch, use Audacity’s change tempo effect, and select high-quality stretching. Also a quick note on pitch, REDUCING PITCH is not an issue with time-stretch or in this case, not checking the box in Audacity will sound fine–identical to change speed effect which allows pitch to shift like a record.
The small slider in audacity, just below the play buttons does the same, with its own play button beside it.
INCREASING PITCH is what causes that awful robotic sound, which is what time-stretch does when slowing down a song, bringing up the pitch to near original.
Changing tempo with the high-quality effect in audacity will sound a little bit odd, but light-years better than the simplistic quick time-stretch used by basically all software on the entire planet. So if you don’t like lower vocal tones, this will get you fairly close to original sound, but slower speed.
I am very interested to know if anyone does this on a regular basis, and what music sounds good at slower speeds. Pretty Lights works extremely well, as the artist intentionally speeds up vocal samples, so slowing down that music actually allows closer to original sounds and a slower tempo to be enjoyed.