... akg iron triangle beats, what advantages do they have over each other? Which company makes earplugs? ...

Akg is omnivorous, and sound stage is wide. Headphones are resistant to boiling, and the appearance needs to be worked hard. It's very good in terms of price.

The Iron Triangle focuses on female voices and adopts Japanese style. The low-end (below 1000) iron triangle is a joke. However, the tuning of the female voice allows it to evaluate polarization. People who like it call it female poison, while people who don't like it spray it unbalanced.

The beat is ... ugly. Generally, friends who burn it jokingly call it a "ringing necklace" and "a series of fakes with better sound quality than the real thing". Although the sound quality of several headphones is worth listening to, when it comes to price, it can't be compared at the same price. As an earphone brand, it failed, but as a fashion brand, it was very successful.