Constructional Difficulty: Easy to Moderate
This image shows the EFG-Deluxe. This is the standard EFG module combined with the Little-Lag module in one 2U wide panel. This also allows the internal pre-amp to be accessed independantly of the envelope follower and lag circuitry.
An envelope follower takes an audio input and converts it into a control voltage. This control voltage will rise and fall with the overall volume of the input signal. The louder the input, the bigger the output of envelope follower. The Oakley EFG has two CV outputs available, fast and slow. The former is useful for tracking fast moving cymbal and hi-hat patterns. The slower one is more useful in processing single instruments. By using these CV outputs to control VCAs and VCFs it is very easy to create synchronised patterns that keep in perfect time with a drum machine or other musical input. On the EFG-Deluxe, both CVs are available simultaneously. On the standard EFG, a switch determines which one is available from the CV output socket.
Another feature of the Oakley EFG, is the provision of a gate extractor. This part analyses the peaks in the music and creates a gate type signal in time with these peaks. This can be used to trigger envelope generators in time with an external drum loop or click track. Two rotary controls enable you to get clean gate signals from all sorts of input material.
The Oakley EFG comes with a wide range two stage input pre-amplifier. This allows guitars and other external instruments to be processed simply. The output of this section is available on the 2U version and now also the 1U version of the EFG module. You can use this high quality output for driving other modules.
And most importantly it has three LEDs. One showing input overload, one for gate status, and one for a visual indication of the CV outputs.
The EFG can be used in conjunction with lag generators to create 'vactrol' type responses. The Little-lag module integrates perfectly with the EFG to form a powerful pre-amp, follower and lag module in a 2U wide module. Both PCBs are then mounted next to each other behind one panel.
This is an image of the newer layout for the standard EFG in a 1U panel. Notice the new pre-amp output socket and the new switch that selects between the choice of fast and slow follow speeds.
This is the rear view of the 2U EFG-Deluxe. Note the additional Little-Lag board mounted above the issue 3 EFG PCB. Only one power lead is required to supply both modules. Issue 4 boards are similar but have the option of fitting a dotcom power header.
Project Downloads
EFG issue 4 Builder's Guide
EFG issue 3 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'.
More information on the Little-Lag can be found here.
Front Panel database
A Schaeffer front panel can be made for the 1U wide EFG or 2U wide EFG-Deluxe.
The databases can be found here: efg.fpd and here: efg-deluxe.fpd.
To read this file 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.
The rear view of the 1U standard EFG with an older issue 3 PCB. Note the three LEDs can only just be seen as they are mounted below the level of the PCB.
Prices
EFG 1U ready made module..........................
145GBP
EFG Pre Populated PCB.................................. to be
announced
EFG issue 4 PCB
............................................ 20GBP
EFG pot kit ..................................................14.50
GBP
EFG pot bracket kit
............................................ 3GBP
The prices above refer to the parts needed to make the 1U version of the EFG. To make the 2U EFG-Deluxe, you will also need to buy the Little-Lag PCB and parts found here.
The Pot Kit contains the correct type and quantity of Spectrol 248 & BI TT potentiometers to complete one 1U EFG 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 EFG 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.
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