Can I use more diodes to reduce the voltage off a diode bridge?
If your idea is to bring the output voltage down under 9.5V you can use extra diodes in series.

But the voltage regulation would be really bad even if you use large capacitors. Since the forward bias voltage of diode is a function of forward current, then the effect gets multiplied n times the number of diodes you have added. Not recommended to power semiconductor chips, Please use a proper regulator instead.

Vt    Vf1  Vf2   Vf3 
o----|&gt;|---|&gt;|---|&gt;|---| Vo
                       \
                       /
                       \ RL
                       /
GND        If          |
o-----------&lt;----------|

Vo = Vt - ( Vf1 + Vf2 + Vf3 );

Where,
  Vt is the voltage at positive terminal coming out of the birdge rectifier.
  Vf1, Vf2 and Vf3 are the forward biased voltage of Diodes.
  RL is the load resistance.