The VPD variable inline attenuator can be configured as one of the following:
- XLR-F to XLR-M, 6dB to 30dB balanced microphone level attenuator, in eight 3-4dB steps.
- XLR-F to XLR-M, 6dB to 48dB balanced line level attenuator, in eight 6dB steps.
- 1/4″ TRS to 1/4″ TRS, 6dB to 48dB balanced mono line level attenuator, in eight 6dB steps.
- 1/4″ TS to 1/4″ TS, 6dB to 48dB unbalanced mono line level attenuator, in eight 6dB steps.
- 1/4″ TRS to 1/4″ TRS, 12dB to 48dB unbalanced stereo line level attenuator, in four 12dB steps.
- XLR-F to XLR-M, passive notch filter, -7dB at 250Hz to 6kHz in eight 2/3 octave steps. (coming soon)
Custom values for attenuation and input impedance are available on request.
Microphone level pads are intended for use with condenser microphones on loud sources. Microphone level pads have an input impedance of approximately 2KΩ and will thus pass phantom power with minimum voltage drop. Maximum input level is +20dBV.
Line level pads have input impedance of 7KΩ or higher and are thus not intended for use between microphone and amplifiers, but rather between line level outputs and inputs. Maximum input level is +30dBV.
The passive notch filter is designed for feedback rejection in live sound applications. The 2/3 octave bands are designed to cover the midrange frequencies where feedback typically occurs. It is especially useful as an inline microphone filter where a parametric or graphic EQ is not otherwise available, as with certain instrument amplifiers. The notch filter has input impedance of 1.2KΩ and insertion loss of -3dB. The passive notch filter will pass phantom power with minimal voltage drop.
All VPD XLR inline attenuators/filters are directional balanced (“U” pads); the TRS attenuators are symmetrical balanced or unbalanced (“H” or “T” pads). The VPD attenuators use precision 1% tolerance resistors, so matching between units and channels in stereo units will typically be within 0.1dB.