
"Why an new EQ-board?
Well, most mixers, FX devices and so on nowadays have balanced inputs/outputs. So why shouldn't such an old baby like the Chroma get that feature too? On the other hand the nearly obsolete CEM3360 VCAs on the EQ-board should better used as a replacement part on a faulty DVB as substituting them isn't an easy attempt for some reasons. The circuit is simple: a quad VCA SSM2164 (Z1) replaces the two dual CEM3360 VCAs. It's a current-in current-out device with 33mV/dB controls. Note: This not an OTA! The core looks more like a multiplier (see Figure 1). The (audio) voltages 0-3 coming from the CMB are converted into currents by the 30K resistors. The 510Ohms 470pF series pad from input to ground prevents oscillation."
No comments:
Post a Comment
Note: To reduce spam, comments for posts older than one week are not displayed until approved (usually same day).