[lawrecedent]

I have the K619 and they are my first step into on ears so I by no means have a varied experience. I came from owning a large number of iems my favourites of which are my ue triple Fi 10's. After in iem's and especially the triple fi's I was initially disappointed by first of all the volume and secondly the involvement in the music that they produced but have realised this is a natural thing as iem's create the feeling of the music actually being located inside your head. At first I cranked the volume up high to compensate for this and found them highly revealing cans with a large amount of bass presence. However, as I have grown accustomed to them I have been able to adjust to lower volumes and have still found them to be quite revealing I.e. strong bass reproduction but not sacrificing the highs. Middle are also well reproduced with Adele's vocals really coming to life. These are by no means neutral or audiophile in their sound reproduction but are warm and fun to listen to especially on edm or r&b/rap etc. I don't know if I believe in burn in but as my ears have adapted to their different sound signature over time I must say I thoroughly enjoy listening to them. At the £50 new I paid for them on Amazon I don't have any major complaints, although they do crush my ears after several hours. They are definitely heads and shoulders above any of the beats I have listened to. Hope that helps people who are wondering, just a shame I can't compare them to any similar cans. Still they've inspired me to try out some others with the k550 and ue 6000 next on my list.

 

[egosumlux]

  I had the K451's and found them quite fun and bassy, however as Iso just mentioned, the treble and mids were sacrificed! I did find them to have quite a lot of detail for a pair that were so bass heavy (to my ears at least).
 
The AKG k451's definitely benefited from at least 20 hours of burn in before it's potential was unlocked.A lot of the complaints probably stemmed from the fact that people were making judgements listening to them straight out of the box. Never a good idea.

Some drivers also need tiem to warm up such as RE-400 they start to sound their best after an hour