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AM-10HD / Aug 2008
A M - 1 0 H D G U I
VBMS Style
Two VBMS styles plus an OFF setting are available.
Off
– The VBMS is out of the circuit.
Hard – Has a transfer function occupying approximately 1dB of transition
amplitude. The VBMS action in this mode is moderately abrupt and generates
low order harmonics. In a process that borrows from the technology of the
Timbral mode, used in the AP‑2000 and FM‑2000 products, we mathemati‑
cally manipulate harmonics, except the third and fifth.
Soft – Setting operates with a transfer function occupying approximately 1.75dB
of transition amplitude. The VBMS action at this setting is less sharp than the
Hard setting, and it generates even fewer harmonics. When the Soft setting
is enabled we mathematically manipulate energy above the third harmonic.
The two modes may appear on the surface to be almost identical because of
the small amount of difference in their transfer functions. However, because of
the amount of program energy being handled and because the transition slope
is larger on the Soft setting there is a
significant
difference in the way the two
clipper styles sound on actual program material.
VBMS Output
Adjusts the ratio of bass at the output of the VBMS algorithm and in very
general terms may be thought of as a “low bass” mix control.
Generally speaking, the VBMS Drive may be adjusted to taste. However, care
should be exercised in the setting of the VBMS Output control because settings
above approxi0.0dB will almost certainly allow bass to confuse the
main clipper’s distortion masking scheme and may increase distortion on some
program material in quite strange and non‑intuitive ways. Like VBMS Drive,
the VBMS Output is adjustable over a range of +/‑10dB.
Comparison of VBMS Operating Modes
