The best shape is a function with many variables including where the bulk of the data is expected to occur and what the average luminosity will be for that data.   This directly effects the amount of noise.

The decision on choosing the precision shaping time was based on the desire to make the correction factors needed to correct for differences in channel to channel capacitance and cable lengths.  This was as small as possible while still using most of the available charge.

the originally designed shaper hybrid will be split into two smaller hybrids.   One contains the shaping and trigger pickoff.  The other contains the dual gain path required to maintain the full dynamic range.  This split design only added a few more pins to the chip, but no new parts..

The preamp output decay produces an undershoot in the shaper output according to model runs created by SPICE.  In order to prevent this undershoot and cause the shaper output to decay to zero as rapidly as possible, a compensating RC circuit is added to the shaper circuit.

The shaper hybrid also contains the trigger pickoff circuit.  The signals for each channel is obtained by a hard differentiation of the preamp output.  The signals are summed on the BLS motherboards to form trigger tower signals.  The addition is done in two stages, to minimize the effects of capacitance and limit the required gain at each stage.  The summed signals will be converted from what the calorimeter measures to another measurement.