There are many great headphones in this SUB-$150 category , I have a good amount of headphones in the range and have tried a good enough of them to know what to expect in this category
The HFI-450 remains to be one of my favourite because of its unusual characteristics , hard to see in this price range
The first is the grain , its almost grain free , technically it should mean its transparent hence it should image well , well ...it doesn't because of the crazy roll-off in the highs , neither is it 2db nor 3 db its way more than that
I don't mind a dark sound , I love it ...personally I don't mind it at all , its a nice break from the M50s with their crazy treble and grain , most definitely better than the v6/7506/zx700 in terms of clarity better than the HM5s as well in terms of grain
Science says closed back headphones with their resonance in the chamber usually are more grainy compared to open backs , well....I would like to disagree the dt770s and HFI-450s being closed have no grain ....over these last 6-7 months I have been doing a lot of reading and research on sound science and its easy to say that damping etc comes second , membrane/driver design comes first.... which seems to be lacking in the R&D new companies are doing nowadays , I'm getting a bit off topic but .....I had to include this
The sound is pretty solid for a home headphone not so much for the studio obviously because of the the unusual response , the bass extension is pretty good ...although the graphs show early roll-off , I like it a lot
The Mid-Range is smooth until you go up to the sibilance region where you feel that spike , again one of the first headphone I have heard with a roll-off in the treble and has a sibilance issue , weird
If you like that sparkle in the highs then the Ultrasone will not please you , there's just a crazy dip for any high frequency extension energy , so...not very detailed
The overall sense of space is a bit congested which is okay considering its a closed back , the lack of grain makes up for that , the bass although accentuated is very tight and holds up with the music , the texture quality seems to be fine not as good as the extended natural bass of the zx700 , compared to the Sony , the bass definitely sounds unnatural ...I really don't know why ?
Its obviously a coloured sound , useless for the studio or any critical listening but....the sound is very special , I haven't heard any headphone in this price range which lacks grain ...this makes the Ultrasone a very special headphone at least for me
A highly recommended product , I scored it for $80 at OrbHeadphones NYC ...for that price I could not be more happy , have a good one guys !
Video Review on my YouTube Channel -
Update 1 -
EDT250V - Seems like these were made for the HFI-450s , gone is the rolled off treble ...say "Hi !" to extension
These pads are almost perfect , highly recommended , makes these fabulous headphones even better