Xena Voice Card Sets

Filter Options: These are sets of 6 filter boards for the Xena desktop synth.  They are preflashed with stock firmware and NOT calibrated.SMR Filter: This filter uses the same topology as the Shruthi SMR4mkII. It is a low pass 4 pole OTA-C filter. Its a smooth "Rolandish" type filter4P Filter: This filter uses the same core as the Shruhti 4-Pole Mission but only offers the LP4 output. I would characterize the 4P filter as a a bit fuzzier than the SMR typeSVF Filter: This filter board features a 2-pole state variable filter with low-pass, band-pass and high-pass modes. It is half of the Shruthi SVF Filter3109 Filter: Based on the 3109 OTA this filter is the same topology as what was used in the Roland JX and Juno synthesizers   Disassembly instructions:1. Remove the six screws on each side of the device 2. Remove the one screw of the front of the device 3. Remove the 2 screws on the back of the device and the 7 nuts 4. The top of the device can now be removed by opening from the bott