Integrated Circuit - SSI2144, Ladder VCF, Sound Semiconductor
The second of two legendary SSM filter updates, the FatKeys™ SSI2144 is a dedicated four-pole low-pass ladder filter with on-chip resonance control. Original designer Dave Rossum did a number of performance updates such as lower noise, improved control feedthrough, and logical pin grouping but otherwise left this sweet-sounding VCF alone. The SSI2144 reprises the SSM2044 of legacy chipmaker Solid State Micro Technology, which many believe to be the best-sounding analog synthesis filter IC ever produced. Based on Dave Rossum’s patented classic improved ladder topology, the SSI2144 allows rich tonal characteristics that showcase the very best attributes of subtractive synthesis. The SSI2144 uses the same internal circuit as the SSM2044 but incorporates improvements by the original designer and takes advantage of modern process technology.
Integrated Circuit - SSI2140, Multi-Mode VCF, Sound Semiconductor
The SSI2140 is a new-generation voltage controlled filter that provides four highly-configurable variable transconductance cells for a wide variety of pole and mode combinations, and adds significant new features.
Integrated Circuit - AS3320, Multi-Mode VCF, Alfa, 18-Pin Dip
The AS3320 is Alfa’s version of the CEM3320 IC. The AS3320 is a high performance voltage controlled four-pole filter with on-chip voltage controllable resonance IC. The four independent sections may be interconnected to provide a wide variety of filter responses, such as low pass, high pass, band pass and all pass. A single input exponentially controls the frequency over greater than a ten octave range with little control voltage feedthrough. Another input controls the resonance in a modified linear manner from zero to low distortion oscillation. For those demanding applications, provision has been made to allow trimming for improved control voltage rejection. Each filter section features a variable gain cell which is fully temperature compensated, exhibits a better signal-to-noise ratio and generates its low distortion predominantly in the second harmonic. The device includes a minus two volt regulator to ensure low power dissipation and consequent low warm-up drift.
Integrated Circuit - AS3109D, VCF, Alfa, SOIC-16
The AS3109 is Alfa’s version of the Roland IR3109 VCF in an SOIC package. The AS3109 is a high performance voltage controlled four-pole filter. The four independent sections may be interconnected to provide a wide variety of filter responses, such as low pass, high pass, band pass and all pass. A single input exponentially controls the frequency over a range greater than 15 octaves with little control voltage feedthrough. AS3109 features high input impedance buffers. Features
- Voltage controllable range – 15 octaves
- Accurate exponential frequency scale
- High input impedance buffers
- Wide transconductance range
- Low input offset voltage
- Low control voltage feedthrough - 45 dB typical
- For electronic music
Integrated Circuit - DAB2140, Multi-Mode VCF, Sound Semiconductor
The Sound Semiconductor DAB2140 is a pre-soldered DIP converter for the SSI2140. This board features the SSI2140 and two decoupling caps for the V+ and V- inputs. The pinout is labelled on the board and matches the SSOP pinout. This adapter features a 20 pin DIP base with a .600 in. width. The pins are standard male headers so 2.54mm female headers are recommended for socketing the board. For the SSOP version, please see P-Q-SSI2140. A refresh of a classic design, the FatKeys™ SSI2140 preserves mojo of the beloved SSM2040 and adds temperature compensation of gm cells and the exponential control port. A "Q VCA" is provided to allow easy resonance control as well as various options for Q compensation.