Ja, dann werde ich mal nach den optimalen Einstellungen suchen
Wenn alles nicht hilft, dann muss ich wohl wieder Geld investieren 
zu den fotos von oben habe ich auch den text gefuden leider nur auf englisch:
First, let me start out by saying that I think the Logic 7 sound
from 250 Hz and up sounds great for a stock sound system. It’s just that lower
end that needs a little help. A little more power to the speakers under the
seats, and a sealed sub with some good power to drive it is the answer.
So, first I tapped into the sub wires coming out of the stock amp, split the
wires into 2 separate inputs (Sub & speakers under seats) and put them into
an Audio Control LC6i line converter. This unit also has a sub gain control,
which I mounted in the center console.
From there I went into one of the new digital amps from JL, an HD 600/4. I must
say that these new HD amps from JL are very impressive! This amp that I picked
will send 150W to the speakers under the seats, and 300W to the Sub. Speaking
of the sub, I choose a JL 10W3v3, which I find to be very musical sounding in a
small sealed enclosure.
Next was building the sealed enclosure (about .625 cu ft ) for the Sub … I
choose a rear firing box and I decided to mount the equipment on the front of
the box, so you can get at the stuff when you put the seats down.
Next was tuning the gains and x-over points between the subs and under seat
speakers. I found bring the x-over point up a bit on the speakers under the seats
made the transition between the Sub and seat speakers work best, and I could
drive the seat speakers a little more with a higher x-over point.
Now the results ….. all I can say is ‘HOLY F’n CRAP!!’ This system sounds
incredible!!! I wasn’t sure if I should add more power or replace the other
drivers with Morel, or Dynaudio, or just keep them stock. Well boys and girls,
no need for changing out all the drivers … just boost the low end of your
system and you will be jumping for joy!!