The Analogue Systems RS-650 Echo/Reverb module is a combination of the RS-310 Reverb/Chorus and RS-440 Analogue Delay.
They are based on the most versatile BBD (bucket brigade delay) chip out there: the MN3011. Thanks to this chip, the RS-650 offers both delay and reverb settings in one module. Flip the switch to quickly change between delay or reverb effect.
The MN3011 BBD was an intermediate stage between normal delay chips and digital reverb. It has multi-tapped outputs which are configured in a way that simulates multiple acoustic reflections with a non-overlapping pattern. This yields a semi-reverberant characteristic and produces a warm, dense and organic reverb sound.
In Echo mode the delay time can be set with the according potentiometer between 75 and 200 milliseconds and with control voltages, from 50 to 2000 ms. Beyond a delay time of 300 ms the internal clock frequency becomes audible which can be minimised by using a low-pass filter. Create a chorus effect by sending an LFO to the Delay Time CV Vary input. Adjust the speed and depth to taste! The intensity of the effect is voltage controlled thanks to the Dry/Wet CV input. This offers further creative possibilities.
The resonance parameter sets the number of repeats and can be considered as the feedback parameter. It goes up to self-oscillation which will work even without input signal. Try sending a trigger into the audio input!
All in all the RS-650 brings a great vintage and oldschool BBD sound to the table!