Tiptop Audio Z2040 4-Pole Low Pass VCF (8HP)

Full Description

Based On Renowned Classic Filter Chip

The Z2040 Voltage Controlled Filter is based on the famous SSM2040 filter chip. It is an enhanced 4-pole VCF with a discrete circuit design with significantly extended capabilities compared to the vintage sound of the chip it is based on. With Tiptop Audio's huge, lush signature sound, the Z2040 delivers thick low-end with rich leads and astounding dynamics. It features inputs to allow modulation with audio frequencies, delivering colourful and interesting tones and textures. The circuit is non-linear, and with the Resonance feedback maximised, the Z2040 can be converted into a pure sine-core voltage-controlled oscillator, making it ideal for creating a wide array of timbres.

Gain Knob & Configurable VCA

The Z2040 is equipped with an audio VCA that can be configured at either the input or the output of the filter (adjustable using headers and jumpers on the unit's PCB). The gain knob on the front panel functions completely independent of the VCA, and only sets the input gain regardless of the position of the VCA (VCA on input or output). When the VCA is configured to the input, then the audio from the VCA and from the gain knob are mixed together. When configured at the output, the gain knob only affects the input. This allows you to maintain control of the input gain no matter what the VCA is configured to.

Unique Gain Stage Configuration

The Tiptop Audio Z2040 4-Pole Low Pass VCF features three different positions for the gain knob with differing behaviour:

• MIN (Just before 0dB): When set somewhere in this range, the module will behave similarly to the SSM2040 filter chip, with a similar sound as well. The ratio between resonance and input signal is set in a similar way to that of the original SSM2040. This means that the input signal's volume will drop when the resonance is increased. This range has low distortion, and will reproduce that classic 'sweet' sound of the SSM2040.
• 0dB: In this spot, the unique resonance-gain-compensation circuit will kick in, providing a gain compensation of the input signal as the resonance is increased. This gain compensation loop dramatically reduces the drop in volume of the input signal when the resonance is increased. This results in the production of resonating sounds with additional punch.
• Just past 0dB to - max.: This range caused the Z2040 to behave in a non-linear fashion, resulting in some interesting sonic characteristics. Any sound wave with a magnitude of 10Vp.p will be clipped by the filter core. This clipping will get deeper as gain is increased. This kind of filter core clipping is soft and smooth, and will add harmonics to the incoming sound. When increasing the resonance in this range, the output gain will also increase. At maximum settings, the module will output a signal of up to 21Vp.p. This special feature is inherent from the structure of the resonance-gain-compensation and will result in the Output adding additional clipping and distortion to the filtered signal and the resonance sine shape. The output signal amplification adds a hard sound clipping by driving the output op-amps to their rails. This high gain could also prove useful for driving other modules following the Z2040 in the signal flow to make them distort and clip the signal even further.

VC-FM

The Z2040 features an input labeled FM. The module adds a unique feature, providing the ability to modulate the magnitude of the FM signal by another signal. This is achieved by placing a VCA on the FM line. This simple yet effective structure provides a variety of modulation tricks. The most common use will be to modulate the magnitude of an envelope or LFO with another envelope and/or LFO. On the other hand, modulating the FM signal using audio waveforms will provide additional harmonic content to your FM signal.

Self-Oscillation

The Z2040 VCF can be used to generate a pure sine wave and act as a VCO. With no signal on the input and the resonance set to its maximum position, the module can oscillate a very low distortion sine wave. Despite not possessing an exponential 1V/Oct input, the Z2040 will track precisely over roughly seven octaves using MOTU Volta calibration. Modulating the VC-resonance and/or the FM inputs in self-oscillation mode will transform the sine wave and add harmonics.

Specifications

General

• Width: 8HP
• Depth: 42mm
• Power:
  • +12V: 20mA
  • -12V: 20mA

Resonance/VC-Res

• Input Impedance: 10 K Ohm
• Input Range: +/-2.5V

FM/FM-IN

• Input Impedance: 220 K Ohm
• Input Range: +/-2.5V

VC-FM/VC-FM IN

• Input Impedance: 22 K Ohm
• Input Range: +/-2.5V

Gain/VC-Gain

• Imput Impedance: 30 K Ohm
• Input Range: +5V

Impedance

• Audio In: 35K Typical, 10K At Maximum Gain
• Audio Out: 220 Ohm