The Tau Hydrae and Azure Dragon have been working well in both jamming and recording situations but both have had an upgrade. There's a demo video here.
Tau Hydrae - Filter v2
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| The Filter v2 front panel - a much more inspiring design and controls |
I found the basis for a design which would make up two
filter stages using a pair of CEM 3320 filter chips. One was doing a 4-pole low
pass and the other a 4-pole high pass. Combining these two filters would make
for some interesting results and I could achieve most configurations of filter I
would want.
I was concerned about the panel space as I could only use the space that existed as I was effectively putting two filter arrangements where previously one lived. The list of possible modulation sources and configurations was quite high, so some options had to go. I managed to make it work with the only real casualty being the modulation for the resonance control. It was worth the sacrifice but I did gain a Key Follow feature.
The filter controls are straightforward: select HP mode (2 or 4 pole), adjust cutoff frequency, and toggle active/bypass. The low pass filter has identical controls. Modulation options are below, with key follow always active—choose half or full keyboard control voltage. Key follow naturally adjusts cutoff frequency as you play across the keyboard.
The result is not perfect as I think the resonance for the high pass needs some work. It could be schematic design or a setting of which I don't know now. I can say that it is more interesting for creating sounds.
Azure Dragon - Spring Reverb v2
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| The new Spring v2 - the controls remain the same as v1 |