I am really impressed with the performance of ATH m40x, I was planning to buy Beyerdynamic DT770 pro But I was very confused because there so many options and it was getting harder for me to choose the right one then I spoke to the Product specialist and told that I want a good studio monitoring headphone. He said the Audiotechnica m40X is a very good headphone.Then I asked about the Beyerdynamic DT770 pro. He said this is also a very good headphone but in your budget i suggest to get Audiotechnica when I heard audio technica m40x, I immediately satisfied. My friends said that why you don't take m50x is the latest, but I saw in the review that people were saying that this is not giving flat response m50x is more bassy compare to m40x and Dt770 pro. And i also Read Beyerdynamic DT 770 pro But Beyerdynamic also got a great rating.Then product specialist was told me Obviously Beyerdynamic DT 770 pro have much better sound quality for "monitoring" as compared to Audio-technica ATH m40x But in the Beyerdynamic DT770 pro a downside is that its build quality is not as strong as Audio-technica ATH m40x or m50x , if you are a rough user, then you will have to use and handle it very carefully, but Audio-technica m40x or m50x is the best in terms of build, in terms of convenience, in terms of feature and also in terms of replaceable stuff.For beginner music producers the sound quality is satisfactory, thank you bajaao and product specialist for giving me great suggestions