Constructional difficulty: Moderate in 1U format, More difficult in 2U format.
The 1U format 'filter core' Journeyman filter. This offers the basic filter module without the extra CV and audio mixing that the full width 2U module provides.
If our Superladder and SVF are well behaved perfect sounding filters, then this one is the rude boy of filter design. Its completely unlinear response and discrete circuitry gives it a unique sound of its own. Modelled after a classic Japanese filter design of the mid to late 1970s, the Journeyman can be configured in either -6dB/octave high pass or -12dB/octave low pass modes by the flicking of a switch. When two of these VCFs are used together, one in HP and the other in LP, then the effect is astounding.
The filter heart is made entirely from a single ended discrete design and uses four matching diodes as the control elements. The filter behaves differently depending on the input signal level hence the 'drive' pot on the front panel. Turning this up allows the filter to be overdriven. At full resonance the filter will oscillate across most of the audio band.
The design is intended to fit into a 1U wide 'filter-core' module or a more fully featured 2U wide panel with seven control pots.
The 1U 'Filter Core' format is our new way of handling filter modules. Although the 1U module can be used as a filter module on its own, it is expected that users will make use of external mixers to control CV and audio levels going into the filter. In this way, you will be able to have a collection of space saving 1U filter cores that can be used with any generic mixer module. The Oakley Multimix is an ideal choice for a handy mixer module.
For the 2U design three audio inputs are provided each with its own attenuator. Three CVs can control the cut-off of the filter. One is fixed at approximately 1V/octave, the other two have input attenuators. CV2 features a reversible type attenuator with inverting/non-inverting properties.
The board size is 83 x 143mm.
The 1U version of the Journeyman VCF. Note the unused headers near the pots, these would be used on the 2U version for connection to the off board pots.
Sound Samples
All the following samples recorded with a small Oakley set up comprising of one VCO, one VC-LFO, one Journeyman filter, two ADSR/VCA and one midiDAC to control them all.
jour-seq.mp3 1.40Mb 1min 1s. Using the low pass output. Simple sequence with an input from the sawtooth output of a single Oakley VCO. The filter is manually being swept via the 'freq', 'resonance' pots and altering ADSR sweep depth.
jour-seq2.mp3 1.45Mb 1min 4s. This time using the high pass output using the same simple sequence whilst the cut-off, sweep depth and resonance controls are tweaked.
jour-hit.mp3 1.28Mb 56s. Various one shot hits and blats at different settings of frequency, resonance and drive.
jour-sol.mp3 0.44Mb 19s. Low pass output; a bit of resonance, fixed cut-off frequency and a bit of reverb for ambience.
Prices
Journeyman 1U ready made
Module......................... 165GBP
Journeyman Pre Populated PCB................................. to
be announced
Journeyman VCF issue 1 PCB
................................... 20GBP
Journeyman VCF issue 1 pot kit .................................
12GBP
Journeyman VCF issue 1 pot bracket kit
................... 4GBP
The Pot Kit contains the four Spectrol 248 or BI TT potentiometers to complete one 1U filter core module.
The Pot Bracket Kit contains the correct type and quantity of Oakley-Spectrol pot brackets and extra Spectrol nuts required to complete one 1U filter core module.
Click here for full price list and ordering details. All prices include VAT at UK rates. Shipping and postage is additional to these prices.
Project Downloads
Journeyman User Guide
Use 'save as...' button to download and view the files. IE users need to right hand mouse click and then choose 'save as'. Links to schematics are available to purchasers of the PCB or module and will be sent via e-mail when the board(s) are shipped.
Front Panel database
A Schaeffer front panel can be made for either of the two variants of the new Journeyman module. The databases can be found here: 2U format or 1U filter core.
To read these files you will need a copy of 'Frontplatten designer' from Schaeffer. The program also features on-line ordering, so its now even easier to buy your panels from Scheaffer.
The company are based in Berlin in Germany and will send out panels to anywhere in the world. Delivery to the UK normally takes around ten days. For North American users you can also order your Schaeffer panels from Front Panel Express.
Back to projects page: Projects
Back home