Tbh? While I can tell a difference, I couldn't tell you which one is supposed to sound "better".

Are you perchance listening on laptop speakers?

With real speakers or headphones the difference is extremely striking.

For what it's worth, it's very clear to me which is better even on my iPhone's speakers (as well as on my desktop's "real" speakers, of course). Sound preferences are deeply personal, but I'm still pretty shocked GP can't tell.

Consider hi-fi speakers vs monitors. The difference is very clear, but it would be somewhat wrong to call either "better".

This is actually a common misconception. In blind testing, the average listener reliably prefers the more accurate speaker. There is a talk [1] by Dr. Floyd Toole that is an excellent crash course on the science of sound reproduction and listener preference.

[1] https://www.youtube.com/watch?v=zrpUDuUtxPM

You can hear the difference very well using regular headphones. The supposedly "better" one feels strongly amplified.

I agreed with this so I made the levels equal (as measured objectively with EBU R 128): https://0x0.st/HvXA.wav

The first (DSP processed) clip still sounds much better to me. The first time the unprocessed clip is played it's rather noisy for some reason, that could be room noise picked up in the microphone though. The high end is missing from the second clip almost entirely (anything above 5 khz).

However the DSP clip isn't without significant problems. It sounds distorted to my ear, and slightly pitch shifted as well. It's rather "tinny" sounding. I'd rate both clips extremely annoying to listen to in comparison to the original which seems pretty well mastered if you like this sort of thing: https://youtu.be/ZRtdQ81jPUQ?t=52

It's hard to tell how much of this is due to it being a quick and dirty recording. Also, being able to play audio at higher volumes is supposed to be one of the big advantages of using this DSP chain, since temperature spikes created by transients are managed in software. (Just speaking for myself personally, I've never felt that my non-Apple laptop speakers needed to be louder, even without DSP.)

The big issue I see with trying to compare the DSP profiles of two different clips, as recorded by a cheap consumer microphone in a compressed audio clip is that we're unable to tell whether asahi's DSP is actually better or just happens to match the sweet spot of the phone's microphone DSP profile.

That's precisely the issue I've got – yes, there’s a difference, but both sound like shitty speakers just with different EQ profiles applied to it. It's still compressed to hell and extremely tinny no matter what.

It's not just loudness, the DSP version also has a much more natural flat/neutral sound profile.

If you are interested, there are corresponding frequency response measurements from a measurement microphone in a sibling thread.

A lot of people are talking about it as if it's self evident which one is better. Or that if I played the sound on a certain device it would be obvious. Can someone state what part of the video is the good part?

The center audio is cut dramatically, making it much harder to hear the voice. It was very obvious to me, on an iPhone.

It starts with the DSP enabled, so that's the "good" state. Then it's toggled off and on a few times.

It honestly probably would help a lot of people to hear how it's supposed to sound first. It's easy to tell how striking the difference is, but it's probably a lot more obvious how much better it is when you're comparing to a "ground truth".

https://youtu.be/ZRtdQ81jPUQ?t=52

The audio is so outside of the stuff I normally listen to that I don't think I really appreciate the difference.

Totally with you, my 13yo daughter listens to this stuff all day but it's not what I'd use to compare.

Each to their own I guess.

You might be amused/horrified to know, then, that this is (was?) the top track in Japan for many weeks straight (at least according to Billboard and YouTube.)

I can imagine. Most people who enjoy this kind of music probably despise what I hear, too.