i knew 5507 have very good quality inside ,like 6 x dac ,one more than 886 ,and the price was low too, but at av bxxx 's c-hing told me if i don't like 905 then i won't like it ,i owned 905 before , the sound quality was good , but the dynamic was not enough , and the density of sound wall was low,i mean surround was too simple for me(no space feel at all) , thats why i m wodering is there any change since this is new model and pre amp ?thanks for your advice