STG Soundlabs Vinyl & CDs

Notes: .BAM stands for Buffered Attenuator/Multiple. This 4HP module can be thought of as two functions: a an active attenuator on the top, and a 1 in 4 out multiple on the bottom. The attenuator output is normalled to the multiple. The connection is broken by plugging into the multiple input.

The active attenuator can be configured to be either bipolar (attenuverter) or unipolar, and 1X or 2X gain. This is performed via clearly-labeled jumper blocks on the PCB.

This module is skiff-friendly, with a depth of only 2.5 inches.

Notes: The .COM module contains comparator and divider circuits, suited for audio signals. They generate square waves out any audio signal and create four types of sub-octaves, PWM is possible as well.

The input signal is being passed thru a comparator that creates square waves. Depending on the position of the threshold control and the according threshold CV the pulse width of the signal changes and we get a pulse width modulation. A number of different sub-octaves is generated from the input as well. Follwing outputs are available:

Output 1: direct comparator output. 1%-49% pulse width
Output 2: one octave below input, 50% pulse width
Output 3: one octave below input, 25% pulse width
Output 4: two octaves below input, 50% pulse width
Output 5: two octaves below input, 25% pulse width

One audio input. One comparator output. Four suboctave outputs

Notes: The STG Soundlabs .MIX is the best-sounding mixer available in the eurorack format. It has a ridiculously flat frequency response, only 3dB down at 300KHz, and a very low noise floor.

.MIX also provides a characteristic asymmetric distortion which is a vital part of the 1960s Moog sound, because not only is its makeup gain stage identical to the Moog CP3, but its power rails are virtualised to be identical to the odd +12/-6V supplies of the original Moog systems.

Notes: The .SHN is a 4 hp noise source and sample & hold module. both pink and white noise are provided in the upper section of the module. The lower section of the module is the sample & hold. White noise is normalised to the control input of the sample & hold section, but that is easily interrupted by inserting a cable to the input jack. The trigger input results in a transition time of 200 microseconds and it can accept clock oscillations at rates up to 7 khz.

Notes: Combine two different waveforms into one, using a control waveform (usually a sawtooth), an A input, and B input. Outputs are for slicing and one after the other.

Notes: The .VCA is the best dual linear VCA in the eurorack format. It has a flat frequency response to 3dB down at 500KHz!

It takes 4hp of panel space. Each channel has one signal input, one control input, a switch to select between ac or dc coupling of the signal input and an output. The lower inputs are normalised to the upper inputs, so it is very easy to send the same signal or control input to both VCAs. Its response is unity gain at 5 volt control input.

Notes: The .VCO is an 8HP eurorack analogue relaxation core oscillator with sawtooth, triangle, and sub octave square wave outputs, and an integrated drift generator.

.VCO’s tuning system is unique in modular synthesis. There are three controls: Range, Semitone, and Detune. Range and Semitone are stepped controls on potentiometers.

The Range knob allows you to select wether the .VCO is an audio oscillator or low frequency oscillator. LFO, 32’, 16’, 8’, 4’, and 2’ are ranges most synthesists are familiar with, but the Wide mode allows you to sweep through 5 octaves with the Detune knob.

The Semitone knob sets a positive semitone offset to the oscillator and functions in all ranges. To make common values easier to get to, the root, fifth, and octave all have twice of the rotational degrees allotted to them as the other semitone values.

The Drift Generator could be described as a drunken walk, or perhaps a random wobbulator. In technical language, it is a random, in rate and peak, bipolar linear function generator with smoothing. Some people patch their entire synthesizer to do what this thing has built in! It can move veeeery slowly or squiggle very quickly. Its output is normalized to the modulation input, so it can be easily defeated by plugging a new source into the modulation jack.

Notes: The Mankato Filter is a four-pole lowpass filter with positive and negative outputs at every pole, giving you slopes of 6 dB/oct, 12 dB/oct, 18 dB/oct, and 24 dB/oct simultaneously. The negative slope outputs allow you to use the Mankato as a quadrature sine oscillator with 8 available phases. The Mankato will self-resonate from subaudio to superaudio, and responds to one volt per octave through its unattenuated control inputs. When resonating, the 6dB/oct outputs are slightly hotter than the others and can be driven to lightly saturate at full resonance. The signal inputs are DC coupled, which allows you to use the Mankato as a voltage-controlled slew limiter at very low cutoff frequencies.

Notes: This filter is not a clone of the ARP 4072 submodule. It does, however, have an identical topology with the same transistors and operational amplifier array. Some people may find this is close enough to use the "C" word but not at STG Soundlabs, so in tribute to the origin of this filter design it is called the Post-Lawsuit Lowpass Filter.

Notes: There are two famous 3 pole diode ladder lowpass filters. One of them was in a little silver box of a synthesizer with integrated sequencer that was used to make "acid tracks" and the other one was in a big suitcase of a synthesizer with a silver faceplate and semi-integrated sequencer that was used to make tracks while on acid. This is the latter.

This module features a PCB designed by Detachment 3 Engineering via Yves Usson.

Review: STG Soundlabs' first drop is a wild ride. First up, Suit & Tie Guy goes up against Dorian Electra on 'Fa$t Ca$h (Easy Credit & The Economic Cra$h)' which gets remixed by Objacktivist into eight minutes of bendy deep house with lashings of Ibiza soulfulness. The Lorenzo Vektor is a wild footwork remix with drums piled up on top of one another and the vocal chopped and diced into pieces. On the flip is a star-gazing synth house exploration of outer space and then a killer electro-funk jam. One of the most unpredictable EPs we've heard in ages.