Oakley VCO 1U User Manual Download Page 4

Also available are two octave switches. These affect the two keyboard control voltage (KCV) 
outputs of the module individually. This each VCO, or VCO bank, can be raised or lowered by 
one octave at a flick of a switch. Each KCV output uses a low impedance cable driver to 
ensure no droops with long signal runs and multiple loading.

Although this module was designed to work with the Oakley buss, which pipes around KCV 
and gate signals around your modular, the input and output sockets on this module can be 
assigned different purposes so as to suit individual requirements.

VCA control input is optionally low pass filtered so as to reduce stepping artefacts from midi 
generated CVs. This low pass filtered output is available via the VCA CV OUT socket so you 
can use it to control other modules.

The internal LFO outputs are available individually from the front panel as both sine wave (+/-
5V) and square wave (+5V, 0V).

More about the Oakley Buss and Module Normalisation

The Oakley buss is a three way connector found on various modules. Pin 1 carries the 
keyboard CV (note control) and pin 3 carries gate (note on or off). The VCO Controller 
module taps into the Oakley buss and creates two new busses for each VCO bank. It also has 
a buss through feature for easy wiring

The word buss is perhaps a little grand for something that has just two control lines and a 
single ground. However, it still adheres to the principle of a common set of conductors that is 
available to all modules.

Normalising is the process by which some signal paths are already made for you. In other 
words no patch leads are needed to make those connections; they are connected internally 
either within the module or between different modules but behind the faceplates. However, 
normalising can always be overridden by the user. The name itself comes from the use of 
normalised connections on sockets. When a socket does not have a jack inserted it is in its 
normal position. There is often a connection between the signal lug of the socket and an extra 
contact called the NC (normally closed) lug. It is this third lug on the socket that is used for 
the normalisation. Inserting a jack plug will break the connection between the NC and the 
signal lug.

To help us understand where normalisation is useful consider a VCO with a 1V/octave socket 
on its front panel. It is most likely to be used to for a keyboard control voltage (KCV). To 
connect KCV to this socket one would ordinarily need a patch lead. But imagine a system 
where you have four VCOs and two VCFs that all need the same KCV signal. It can take 
many patch leads to do this; seven if you have a large multiple panel. Now suppose that the 
NC lug of every 1V/octave socket is connected to a common KCV bus. All six modules can 
now be driven without the need for those seven patch leads. This saves you leads, time, and 
also gives you a better working environment because you don’t have to fight your way 
through a tangle of leads to get to the module’s knobs. Inserting a jack into one of those 
sockets would disconnect it from the KCV bus, so you still have complete modularity.

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Summary of Contents for VCO 1U

Page 1: ...Oakley Sound Systems 5U Oakley Modular Series VCO Controller 1U wide oscillator master module User Manual V1 0 0 Tony Allgood B Eng Oakley Sound Systems CARLISLE United Kingdom...

Page 2: ...he Oakley CV gate buss The twin keyboard control voltage KCV signals that this module generates are connected to the VCOs behind the front panel If you do not have the facility for this you can make t...

Page 3: ...ltiple oscillators Quite often you will require simple vibrato of two or more VCOs Normally this is done by patching one LFO low frequency oscillator to your VCOs via a multiple This uses up a minimum...

Page 4: ...s available to all modules Normalising is the process by which some signal paths are already made for you In other words no patch leads are needed to make those connections they are connected internal...

Page 5: ...s This Oakley standard originally created with the Dizzy issue 1 PCB gave us just two lines the KCV and Gate busses These are accessed by the three way 0 1 headers Pin 1 of each header is KCV and pin...

Page 6: ...to that note as accurately as you can with the coarse and fine controls on your VCO Now remove the patch lead from the VCO s 1V octave input and your VCO will now be receiving the KCV1 signal from the...

Page 7: ...KCV1 and KCV2 Note that tweaking OCT will affect the 1 octave setting as well as the 1 If you tweak the OCT trimmer for some reason you will have to re tweak the OCT one as well OFFSET This trimmer a...

Page 8: ...of Oakley modules If you have a comment about this user guide or have a found a mistake in it then please do let me know Last but not least can I say a big thank you to all of you who helped and inspi...

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