Zerosum Inertia - Metasonix - Full System

Hello!

This is a Zerosum Inertia / Metasonix system I put together earlier this year. In addition to the Zerosum Inertia modules, it has a Metasonix RKP power supply powering the modules and a Modulaire Maritime Victor Alpha 2 XP mixer. It is all housed in an Erica Synths Enclosure and the lid fits nicely over the tubes with plenty of space. The Erica Synths power board and supply has been removed, but can be included when shipped incase you want to use the enclosure for something else.

I'm not breaking up the system. It's an all or nothing sort of deal.

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Module Info:

Zi54 x2:

This is the r54 mkii. Originally produced by metasonix with permission granted to zerosum inertia to put back into production and make available once again.
the circuit design is based on the wien bridge circuit created by max wien.
metasonix applied that concept along with ideas of his own to create an experimental musical instrument for eurorack modular synthesizers.
the best way to describe the function of the 54 is an audio processor that can also be a sound generator.
when used as an audio processor it can be used as a bandpass filter and distortion device.
when the resonance is at about 10 o clock it will oscillate to become a sound generator and add resonant squeal to the filter frequency.
this version has the feedback loop and cv for the drive control.
in this version, when the switch is in the upward position pointing north that routes the output of the 54 back into the freq cv which creates instability and more gain. think of it as a color switch or a wild card.

the drive cv is there to add choppy amplitude modulation.
this input feeds control voltage into the grid of the 6ak5/5654 pentode and is done with the tube and sounds different on every unit due to the unique nature of the vacuum tube.
this cv input is unlike any other vca you have encountered and is not meant to be a precise voltage controlled amplifier. it is there to add rhythmic amplitude modulation and trem effects.
there are no exponential converter chips or otas used.

the freq cv is done with a 5c3/2 vactrol and does the classic splats and bonks when fed a sharp snappy plucky envelope.
it is best to use a modulator with a variable curve and onboard processing to dial in the best curve and behavior of the modulation.
vcs and maths works very well with this circuit and all other vactrol based cv circuits.
hitting this with creative rhythmic pulses creates the classic lazer zaps and liquidy bubbley goopy sounds found in electronic music classics.
vactrol cv is a slewed unique indescribable experience for the experimental musician.

the sound is all coming from a 19kg8 and 6ak5/5654.
the 19kg8 is a tube containing a triode and a pentode which is where the filtering and oscillation happens.
this tube is responsible for the freq and res controls.
the 6ak5 or 5654 which is the miltary version of the 6ak5 is responsible for the clipping and overdrive and amplification effects.

recommended starting positions for the knobs are with freq at about 2 o'clock, res at about 10 o'clock, drive and output at about 3 o'clockand the toggle switch down/south.
slowly turn the the freq knob then slowly turn the res knob to get a feel of how they interact with eachother.
then increase the drive knob and ovserve how the foldover and clipping distortion.
now flip the switch up/north and observe how much the sound changes when turning the drive and out level knobs.

this module requires 400 ma of + and - 12v.
make sure you have a high quality power supply and are leaving headroom and not using it to the full capacity.
linear power supplies are recommended and what the module has been tested and used with.
22hp wide.
33mm rear depth.

Zi53:

Recreation of the Metasonix R53

The left tube is a 12AV7 or 5965 and is responsible for the scrambled fuzz sounds.

The right tube is a 12AU6 and responsible for the ringmod.

500 mA +12 on first power up, 200 mA +12 average load after power up.

200 mA -12.

33 mm rear depth.

22HP wide.

Zi61:

the zi51 is the metasonix r51 circuit, used with permission, redesigned to take 6ak5/5654 tubes (only use 6ak5 or 5654 tubes in this module) and added feedback.
the input knob controls the audio input level. distort controls the bias adjustment of the distortion level.
vca adjusts the amount of cv applied to the vca cv input.
you need to have a cv source applied to the vca cv input jack to get the most results from the vca knob.
feedback controls the amount of signal fed back into the input.
a modulation signal of at least 5v is recommended to insert into the vca cv input.
the module functions best when a modulation source is fed into the vca cv input to fully open the vca level of the module.
the distort and vca knobs interact with each other and the more voltage that is applied to the vca cv input the more effect the distort knob has when turned.
it is recommended to let the module warm up several minutes before operating and to start with settings as described:
level knob about halfway.
distort and vca all the way up(about 5 o'clock).
feedback off (full left/about 7 o'clock).

insert a modulation source of at least 5v into the vca cv input.
it is recommended to always have a modulation source patched into the vca cv input for louder volume and more range and response in knob turns.
get familiar with how the input level knob adjusts the behavior and sound of all the other knobs.
after you have that figured out start increasing the level of the feedback while decreasing the level of the input level knob.
get familiar with how the input and feedback knobs interact with each other.
usually a lower input level with a higher feedback level and distort knob between 10 and 2 o'clock have the most aggressive and noticeable obvious sound changes.