That Vintage Sound
While many people love the sound of vintage gear, much of the new crop of gear promising to recreate the full, rich sound of synths of the 60's and 70's has tried to do it with contemporary components and modern replacement parts. This may lead to a lower price and easier sourcing on the production side, but often at the cost of compromised sound quality and functionality.
At bubblesound I feel a little differently. I believe that the easiest and surest way to get that sound of the past is to use the original components, op-amps and transistors from the 60's and 70's. Much of the character of synths like the Oberheim SEM, ARP 2600 and the Korg MS-20 came from qualities of specific parts used in the original designs which is lost when one subsitutes modern parts for the originals.
While this design philosophy seems to fly in the face of the belief that low noise and presission preformance are the goals of instrument design, I believe this is the only way to achieve the same full and rich sound of the classic synths. Many of my designs are based on classics, expanded and unleashed in ways that we feel fully realize their potential, while preserving their character and sound.
The VCOb is an voltage-controlled analog oscillator based around a classic triangle core VCO. It is similar to the uLFO, but with some improvements. The range of the VCOb is one of the widest in the analog modular world. And like all triangle cores, the real fun is in the FM.
Since we're starting with a triangle core it's easy to produce a real Sine wave output. There is also a Saw and Pulse outputs. The Pulse will almost become fully positive or negative with the pot, and will go all the way open and closed with CV.
The VCOb offers FM in both the Linear And Exponential varieties. There is only one input, unlike the uLFO. and the FM set to full in Expo mode this will act as a second 1V/Oct input for things like transposing.
The tracking is all analog and will give 4-6 octaves, depending on how picky you are. It is very stable and they do track together very well.
outputs: saw, pulse, sine, triangle
range: 10 Second cycles - 21.4K Hz
modulation: 1 fm input with linear and exponential, pulse width modulation
size: 10hp, 60mm (2.5 inches) deep
current draw: 100 mv
see the following videos for more details:
click here to download the user's manual
The SeM20 is a classic 2 pole state variable Eurorack filter based on the Oberheim SEM's filter with the resonance section of the MS20 grafted on for extra bite and the input section modified to overdrive the single, much like the OSCar. The Dual SeM20 manages to put 2 in a 16HP module without sacrificing any of the features or the sound of the original.
The Dual version has a 4 input mixer section. Each channel can be assigned to either filter, to both for either stereo filtering or to get the Korg MS-20 or OSCar dual filter effect. The 4 input mixer and 8 outputs make feedback loops and self oscillation patches extremely easy and almost required.
When the input is at 5(noon) it's full volume. Beyond 5 the filter will begin to overdrive and distort, just like the original SeM20.
In Single Mode both filters act independently with their own Freq pots and 2 attenuated CV inputs each. They are 2 full featured SeM20 filters in one module. In Dual mode the upper Freq pot and CV 1.1/1.2 control both filters. This is great for stereo filtering and would work especially well with the new stereo effects from Audio Damage. There is an offset pot for the second filet when it's in Dual mode and this works like the spread feature on the OSCar. You can feed the same input to both filters, offset the second one and then use the 1 CV inout or the Freq pot to sweep both.
This filter can go from a very smooth Oberheimy sound to aggressive, overdriven acid dipped screeching .
It doubles as a pretty good kick drum, too.
12db High Pass, Low Pass and Notch filter
6db Band Pass
Self oscillation when the High Pass is fed into the input
4 cv frequency inputs with attenuators
Notch Pass balance sweeps between High and Low Pass
current draw: 70mA
The 141 is a EG/VCA/LFO that fills in gaps and helps clear out some case clutter.
The Envelope Generator is based around the Roland SH101/M-140 era transistor EG giving the 141 a very snappy feel.
The EG is sent to the ENV OUT and to a VCA for the velocity sensitivity section of the circuit. The VEL IN is normalized to +12V, so when there is no input the VEL OUT is the same as the ENV OUT. But when positive voltage is applied to VEL IN the output of VEL OUT will vary as the voltage varies. The 141 ships set up for a 0-5V inout for the velocity sensitive VCA. This makes is compatible with most analog sequencers and modules from companies like Expert Sleepers. There is a 0-10V jumper setting on the back to make the 141 compatible with the Beat Step Pro and other CV sources that put out 0-10V.
The INV OUT is an inverted output of the EG with a range of 0 to -10V.
An Audio VCA is included and normalized to the EG by the 2 switches near the Audio Input. The VCA has Linear and Expo responses and the CV can either be the normal EG output or the velocity sensitive EG.
The LFO has a range from about 10 second to a little over 200Hz. The Triangle and Square outputs are always active. The Square is normalized to the Gate IN and when there is nothing plugged into it the LFO loops the EG. When an external Gate is plugged in the Sync switch can sync the LFO to the external gate or allow it to run freely.
Width - 6HP
Depth - 35MM
Draw - +60mA -50mA
LFO Range: 10 sec - 200 Hz
Attack - 1.5MS - 4 seconds
Decay - 4MS - 12 seconds
Sustain - 0-10V
Release - 4MS - 12 seconds
6X1(3X1) 6 Channel Mixer - MIX6
The 6X1(3X1) is a dual 3 channel or single 6 channel or single 3 channel stereo mixer.
In 1/6 mode all 6 inputs are summed to the lower output. The upper output is still active for channels 1-3 and this is useful for an effects buss. In dual 1/3 mode each set of 3 inputs sums to its own output.
The first 3 inputs are normalized to the second 3 inputs and this allows the MIX6 to be used as a 3 channel stereo mixer. When an input is plugged into channel 1 it is also sent to channel 4 unless something else is plugged into channel 4. This allows 3 inputs to be sent to a pair of outputs for a simple stereo mixer.
The mixer is DC coupled so it's good for Audio and CV.
No Bleed, very low distortion, low power consumption and low profile. The perfect mixer solution for any modular synth.
width - 5HP
depth - 25MM
current draw - +40mA. -65mA
The HEXa(s)r is a 9HP module with 6 independent AR/ASR envelope generators and 3 mixer sections for a total of 9 outputs, giving users a huge amount of modulation options with a very small footprint making this the most versatile and flexible envelope generator in the eurorack world. Plus it’s skiff friendly and light on power consumption.
Each envelope generator has a gate input and can either be an Attack/Release or Attack/Sustain/Release. In AR mode the incoming gate is turned into a trigger giving you a simple Attack and Release, perfect for drum synthesis and simple modulation or control over VCAs. In ASR mode the length of the Sustain is controlled by the length of the gate. This makes using an LFO’s modulated Pulse Width output or a sequencer with variable gate length perfect for creating envelopes with changing sustain times, breathing life and variation to whatever the HEXa(s)r is modulating. The LEDs are tied to the output to give users visual feedback on each EG.
The HEXa(s)r can use gates (0-8/10V) or a +-5V to trigger the envelopes. It can accept trigger inputs as well, but when using a trigger in ASR mode there will be almost no sustain as the duration of triggers is very short, usually around 5-10 milliseconds.
The Gates in of the HEXa(s)r are normalized so one gate into EG1 will trigger all 6 envelopes. Each envelope generator can then be set to either AR or ASR mode. OIr you can use the output of one EG to trigger another EG. This can be used to make a type of gate delay for individual outputs or complex rhythm or modulation effects from the Mix output section.
The Mixer section has 3 parts, EG 1-3, 4-6 and All. By using multiple gates and triggering some EGs from other EGs the mix out section can create some unexpected modulation options or very controlled rhythmic outputs. It all depends on what you put into it.
There is a header on the back and included 6 pin ribbon cable that will allow the HEXa(s)r to connect with the upcoming HEXvca without using patch cables.
6 independent EGs. Attack and Release times are around 4 seconds each
30MM deep, single PCB skiff friendly design
Output Level: 0-10V
Interconnectable via supplied ribbon cable to the HEXvca
Power Consumption: 50mA positive, 40mA negative
The HEXvca is 6 independent VCAs with 3 mix outputs. Each VCA is switchable between a linear and exponential CV response. The CV inputs are normalized using jumpers on the back, so 1 or 2 gates or EGs can affect several VCAs at the same time.
With headers on the back the HEXvca can be triggered by the HEXar using a ribbon cable eliminating the need for patch cords. There is also a 6 pin header for the audio inputs for future expansion without patch cables.
The MIX section allows the HEXvca to be a voltage controlled Mixer, channels 1-3, 4-6 and 1-6 have dedicated outputs. The VCAs are DC so the VCAs can be used for audio or CV.
The HEXvca uses SSM2164 VVCA chips that provide plenty of headroom, very low distortion/noise and use very little power. The HEXvca is 7HP and around 30MM deep. You can never have enough VCAs but with the HEXvca it’s easier to have as many as you need.
Power Consumption: +50mA -45mA
XFADE is a dual input crossfading module. The XFADE pot will manually fade between the 2 inputs. The 2 CV inputs will take any +-5V input. When the XFADE pot is at noon and the CV attenuator is open all the way a +-5V LFO will fade from one to the other, completely fading from input to inout.
Since XFADE is based around a pair of VCAs when the CV inputs are at audio rate it becomes an unpredictable ring modulator.
The input is DC coupled so the XFADE module is equally good for panning a pair of LFO to a destination as it is for fading between 2 audio inputs, or one of each for some unpredictable FMing possibilities.
Width - 4HP
Depth - 20MM
Draw - +30MA. -30MA
The Booster Module is a 2HP amplifier to bring desktop synths, drum machines and effects into a eurorack system. It has 4 separate amplifiers.
The inputs are normalized so 1 input can give up to 4 outputs and when the output of one stage is plugged into the input of another stage it turns into a brutal opamp overdrive circuit.
The Booster Stage is skiff friendly and has very low power consumption.
And it’s a guitar/bass input if you like overdrive and distortion
The Reducer Module is a 2HP deamplifier to bring eurorack synths, drums and effects down to line level so they can easily be used with stomp boxes, effects processors and samplers.
It has 4 separate deamplifiers. The inputs are normalized so 1 input can give up to 4 outputs .
The Reducer is skiff friendly and has very low power consumption.
the uLFO is an voltage-controlled analog low frequency oscillator based around a classic triangle core vco running through a series of waveshapers, giving the user an extremely wide range of outputs and modulation options. in the low range the ulfo will take over 60 minutes to complete a cycle and will go up to 40hz. the high range goes from 4 minute cycles at the lowest up to 3.6khz at the top of its range, making this a very good low and mid range vco as well as an outstanding lfo.
the ulfo offers 7 simultaneous outputs; saw, ramp, pulse, triangle, sine and shaped sine and the square output is available as the sync out. the pulse and shapes sine are voltage-controlled and have attenuated inputs. the pulse width modulation works like most others, from going from 0-100% with either the pwm pot or with control voltage. but the shaped sine is fairly unique in the modular world. this allows a sine wave to be swept from a positively biased non-linear triangle down to a negatively biased non-linear triangle. an example of this can he found here.
the two frequency modulation inputs offer both linear and exponential modulation with attenuation pots of the incoming control voltage. in addition to the two fm inputs there is one 1v/octate input that allows 4-5 good, solid octaves of tracking. taken as a whole this one of the most full featured lfos on the market today.
outputs: saw, ramp, square, pulse, sine, triangle, shaped sine
range: high: 4 minutes - 3.6k hz, low: >30 minutes - 40hz
modulation: 2 fm inputs with linear and exponential, pulse width modulation, non-linear sine modulation
tracking: 1v/octave. most users should get at least 4 solid octaves of tracking. size: 14hp, 60mm (2.5 inches) deep current draw: 100 mv
see the following videos for more details:
www.vimeo.com/user1812255/videosyoutube clip #1youtube clip #2
click here to download the user's manual
Power Consumption: +60mA -50mA
PAN is a single input panning module. The CLK pot is the rate for a built in LFO with a range of 15 seconds to 175Hz. The LFO’s triangle output is normalized to CV1. Since PAN is based around a pair of VCAs when the CV inputs are at audio rate it becomes a slightly unpredictable ring modulator with a pair of outputs.
The input is DC coupled so the PAN module is equally good for panning an LFO to 2 different destinations as it is for panning audio from left to right.
When the Pan pot is centered and a +-5V modulator is plugged in and the CV pot at 100% the input will swing from fully left to full right.
Width: 4HP Max Depth: 20MM Power: 30mA@ +12V , 30mA@ -12V
Classic Steiner Parker Diode Filter
The DiOD Filter is a faithful recreation of the classic Steiner Parker Diode Filter with modern inout and output buffers. This keeps the noise to a minimum while retaining everything that made this filter a classic. The DiOD is a unique sounding and versatile filter in a small 4HP package. From soft and smooth to brutal, noisy and chaotic, the DiOD's flexibility will make it at home in any size system.
This filter will track, but not as tight as the VCOb and it will self-resonate; in fact at the upper reaches of the Resonance it's pretty hard to control.
Compact and quiet enough to chain several together for stereo filtering, adding more poles or creating a very resonant phaser.
The 2 CV inputs can be CV or Audio.
Width: 4HP Max Depth: 20mm Power: 50mA@ +12V , 30mA@ -12V , 0mA@ +5V
The VCA4p based on the VCA from the classic Polyfusion modular synth. Unlike many modern VCAs this one centers around an OTA chip, like most VCAs from the 1970’s.
While this VCA may not be perfect by today’s standards, it’s those imperfections that give the VCA4p it’s character and warmth.
This VCA is meant to be used as 4 separate VCAs, a voltage controlled mixer or a combination of both.
By using the jumpers on the back the user is able to configure this VCA to meet their specific needs.
4 Individual VCAs, with either linear and exponential CV response. Input can be audio or CV. Individual Gain and outputs for each channel.
Mix Out - depending on the jumpers on the back of the face plate PCB between 1 and 4 outputs of the VCAs will be sent to the mixer section in addition to the individual outs.
Power Consumption: +60mA -45mA