I was astounded to discover this in my Scope upgrade from 4.0 to 5.0.  Modeled on the classic Lexicon PCM91 the SC-Ambience soon replaced the stock reverbs I was using (both Native and DSP) in all my current projects.  The SC-AMBIENCE parameters are divided into three sections, Main, Reverb and Setup as follows:

• Mix / Width / Levels.  In and Out Levels are self explanatory.  Turn them up and you get more reverb.  The In Width and Out Width can control the stereo width of the reverb effect.  I found that an In Width value of 360 and an Out Width value of around 310 gave a very wide effect.  But turning the Out Width higher reduced the width.  Out Width values of -315 and +45 cause the output to be normal left/right stereo.  Values of -45 and +315 cause "swapped", or right/left stereo.

• Mix.  Turn this up to 100% for the reverb only effect.

• Dry Delays.  To set these, first turn 'Mix' below 50% and 'Dry Mix' above 100%, so that you can hear the Dry Delay effect.  Now turn the Dry Delay Left and Dry Level Left up.  You should hear a small single slap back echo.

• Link Level and Link Length.  Turn these off, and now you can set Dry Delay Right and Dry Level Right to different values than their Left counterparts, giving the slap back some stereo width, as the right delay will now come at a different time than the Left Delay.

• Dry Mix.  This will override the reverb 'Mix' percentage by making the signal more dry (less reverb) as you turn it up.

• Low Freq and High Freq work in conjunction with Low Damp and High Damp to 'roll off' or filter out high and low frequencies.  The best way to use these is to just listen to the sound whilst moving the two red dots on the filter frequency graph, as moving these dots with the mouse will also move the corresponding Freq and Damp knobs (and vice versa).

• Decay.  This is Decay time of the reverb.  Larger values will yield a longer reverb tail however.

• Decay Level.  This is the level of the Decay portion of the reverb.  

• Decay Level Modulation Type.  If you click in the Modulation Type area under the Decay Level knob, you will be able to select 'Modulation Off', LFO 1, or LFO 2 as the modulation source of the decay. The LFO1 and LFO2 options refer to the LFO 1 and LFO 2 sections in the 'SETUP' page respectively.

• Size.  Size of the room.  In order to achieve a long, smooth reverb decay set this value to about 26, with Decay at 99.

• Diffusion.  This is the 'smoothness' of the reverb, set it to max unless you're after a more 'grainy' reverb sound.

• Damp Freq.  Controls the frequency of damping.

• Damping. Controls the amount of Damping.  Using the mouse to move the red dot in the 'Color' graph whilst listening to the sound will help you set appropriate values for 'Damp Freq' and 'Damping'.

• Env Attack.  Attack of the modulation sources (LFO 1 and LFO 2)

• Env Release.  Release of the modulation sources (LFO 1 and LFO 2) 

• In Gain.  Gain of the signal used as input to the LFO sources (LFO 1 and LFO 2)

• Out Gain. Gain of the output of the LFO sources (LFO 1 and LFO 2)

• LFO 1 Freq.  Frequency of LFO 1

• LFO 1 Phase.  Phase of LFO 1

• LFO 2 Freq.  Frequency of LFO 2

• LFO 2 Phase.  Phase of LFO 2

Note:  The LFO setting on the SETUP page are only relevant if you have them selected as Modulation Sources in the 'REVERB' page.  In particular, the Modulation Type of the 'Out Level' will need to be set to 'LFO 1' or 'LFO 2'.

With these settings, you will hear a sort of wavering (modulation) in the tail of your reverb, almost like a slow attack echoing effect.