synthesis technology e490 ladder vcf: silver price : $249.00
e490 ladder vcf: black price : $249.00

the e490 is based on the 5u motm-490, updated for eurorack.

the e490 ladder vcf is a 10hp, moog 904a 4-pole lowpass filter using modern transistors, but exactly matching the characteristics of the original. using these new, matched dual and quad transistors allows the e490 to have lower noise and better tracking than the 904a without changing all the 'quirks' in the sound.

the 904a has several distinct characteristics which the e490 duplicates:
low frequency self-resonance begins at 72hz
there is a mid-frequency 'dip and bump' due to phase shifts
the output amplitude drops as resonance increases
the resonance drops as the amplitude increases
the filter will 'track sharp' past 400hz (it tracks ok 100 - 400hz)
if you push the range trimmer to max, it can oscillate to over 20khz

specifications:
height: 3u (128.5mm)
width: 10hp (50.5mm)
depth w/power cable: 31.6mm
power: 10-pin eurorack (18ma from +12v, 14ma from -12v)
cv input range: 10vpp (-5v to +5v), dc to 8khz
audio input: 50k nominal input impedance, 10v pk-pk
audio output: 12vpp (-6v to +6v), 20hz to 22khz frequency range

panel controls
frequency: sets the initial filter frequency
input 1 & 2: level knobs for the two audio inputs
resonance: sets the initial filter resonance
fm level: inverting attenuator for the fm cv inputs
distortion: adds 2x input gain when engaged

inputs and outputs
1v/oct: 1 volt per octave control for the filter frequency
2/3 oct: partial frequency tracking
fm 1: filter frequency modulation
in 1 & 2: audio signal inputs
out: final output of the filter

click here to read the users manual.