for pitch and one for filter. There are also two separate modulation sources for the built-in twin digital delays. The DSS-1 has two 6-stage envelope generators (one for filter and one for amp). Other features on the DSS-1 are: auto-bend (which allows for a pitch glide up or down to a destination pitch), oscillator sync (unusual for a sampler), and bit-crushing from 12 bits down to 6 bits. Oscillator sync in combination with autobend (on the slaved oscillator) allows the DSS-1 to emulate pulse-width modulation. The DSS-1 architecture is quite complex, which explains the weight of the machine (19 kilograms). Two microprocessor boards are used to control the synthesizer. The first one is built around an i8085 processor, in charge of floppy-disk management, user interface management (LCD and front panel), digital oscillator control. The second one is built around a 63B03 processor, handling MIDI communication, keyboard management and control-voltage generation. The digital oscillators are built around a specialized circuitry (based on ASIC), in charge of playing back samples stored in DRAM. Each DRAM chip stores 262,144 bits, and there are 12 memory chips used in parallel to store the 12 bits samples. A 16-channel digital-to-analog converter (DAC) generates the 16 oscillator signals (8 voices of polyphony with 2 oscillators per voice), being fed into the analog processing unit built around 8 VCF/VCA chips, each of them being controlled by voltages generated from the 63B03 processor board. At the tail end of the DSS-1's audio path are two built-in digital delays. The audio signal from the VCA is converted back to digital, run through the twin DDLs (which can be run in parallel or in serial), and then converted back to analog for the final output. Each DDL has a separate modulation source (separate from the MG section) for modulation of the delayed signals. In parallel mode, the DDL section creates stereo sound by each DDL sending its sound through the unit's separate left and right outputs. The DDL boards are the same as the one used in DW-8000 synthesizer, they are built around a specialized integrated circuit connected to two DRAM chips. This circuit is in charge of delaying the digital signal after its conversion using a successive-approximation register. The design of the circuit is not very common, since it uses the same DAC both to generate the output audio after being delayed and for converting incoming analog signal into