Quote: Interesting findings! Have you tried putting the GMP 400 drivers into the GMP450 enclosures with 450 earpads (or the other way around) to see if there are any change in the sounds, they should sound the same if they share the same drivers. 

I guess the difference between QP400 and QP450 is similar to the difference between dt770 and dt880. The closed versions (qp400 and dt770s) are using a different earpads with the open versions. The velour skin of the earpads of dt770 covers a layer of leather, while there is no leather layer...

what a beyer HD-25!

HD598 is a strange model no. Does it mean that it has a sound signature between those of HD600 and HD580? 

I own D7000 for several weeks. It is a great pair of cans in terms of balance, tone and smoothness. But I sold it because I am not very satisfied with its soundstage, which is too lateral. I prefer a kind of headphones with a more frontal soundstage. 

I've found that SA5000 could be more "musical" or less stiff if some kind of acoustic foam is placed between the driver and the ears. This could be a great phone for symphonies, not only for rocks.

I found some good pieces of wood and want to DIY a woody cup for my DT770pro, so I am looking for the pictures of the inside of a DB DT770s for reference. Can anyone help to show the pictures (maybe the internal structure of the woody cup and the materials fill them). Thanks a lot!

lovely Dt770s, but too expensive to me. I am planning to DIY my woodie dt770s. 

It is so surprised that KOSS stopped the production line of A250 without any good substitute for it.

Quote: Thanks. Not exactly lack "punch sound", but it is just not as "punch" as a dynamic headphone like HD600 does. So I am wondering if the A250 will improve this but still has most of the sound signature of the ESP950, which I like most.

I have a set of ESP950 and like its sound very much! But I am thinking to buy another dynamic headphone with similar characteristics. Any one have listened to both headphones can have any comment? Does the A250 give better dynamic and punch sound than ESP950? Thanks!  

I had five posts before but still not reach the limits.