hmm its interesting how different people experience velour and stock pleather pads ...
Stock pleather pads have warmer sound , with more mid bass quantity and lower sub bass , mids have more buddy and sound is darker sweeter with more clarity but , it sounds a bit "halish" at times , like you in the box ....
Soundstage is bigger and deeper , cuz of the distance between ears and driver ...
velour pads usualy emphase treble and discrease bass , and thats what happens with dt150 as well ...
it does sound more like studio sound , neutral , open , airy ... less clarity and less mid/sub bass , background is not as black as with pleather , and soundstage is less in depth , but more wider....that feeling of openness you get cuz velour let the sound go out a bit ....
it also gives ya higher treble energy , sounds gets more energetic with rock for example but less body in mids and less liquidity , more air ...
so pick your poison ....
i spend some time with both velour and pleather , comfort and that studio like neutrality was cool with velour but i ended up preferring pleather pads , tonality with pleather is more sweet more dark with more clarity and bigger /deeper soundstage , reminds me of vinyl /analog type of sound from the 90s ....
and thats suits my taste.
of course it depends a lot on your gear as well ... its all about balancing the stuff you got in your system to get what u want....