E-MU 1212M PCIe - Manual (Page 44)

4 - The PatchMix DSP Mixer
Mixer Strip Creation
44 Creative Professional
may have to go back and adjust the I/O Settings. Choose “-10” if the input signal is too
weak and “+4” if the signal is too strong.
Digital audio has NO headroom past 0dBFS (FS = Full Scale) and will “hard clip” if the
signal exceeds 0dBFS. Hard clipping sounds bad and will ruin your recording. Hard
clipping occurs because at 0dBFS, all 24 bits are turned on and the A-D cannot measure
any higher level. Analog tape, unlike digital, can be driven past 0dB, with some degra-
dation of the signal.
The MicroDock includes a pair of analog Soft Limiters on the preamp inputs, which
can be turned on or off for each channel in the I/O Settings. The soft limiters automati-
cally turn down the gain whenever the signal level exceeds -6dB below Full Scale.
Below this level, the limiters are completely out of the circuit. The soft limiters allow
you to encode a hotter signal without fear of hard clipping the input. This provides
increased resolution and a better recording. When recording drums, piano and vocals,
occasional peak transients can be tamed by the soft limiters, allowing you to supply the
best possible signal into the MicroDock’s ultra-high-quality A-D converters.
The Digital Audio System includes Insert “Trim Pot” controls, but since they adjust the
signal level AFTER the signal has been digitized, this will not recover any lost
resolution. It’s far better to set the input level correctly in the first place. Trim Pots can
be used in emergency situations if there's no other way to get a hot signal in. They are
designed to optimize the signal levels feeding effect plug-ins.
Trim Pot Insert
The Trim Pot Insert allows you to adjust the level of a signal in an insert location. The
trim pot provides up to ±30dB of gain or attenuation and a phase inverter. The trim pot
also has a built-in stereo peak meter after the control.
Gain/Attenuation
Phase Invert
Meters
You might use a trim pot to boost or attenuate a send or return from an external effect,
or to drive an effect device. Certain effects such as the Compressor, Distortion, and
Auto-Wah are very level dependent and like to see a good, strong input signal. If you
are working with a weak signal, you can improve the performance of these effects
inserting a trim pot and boosting the gain.
Trim pots can be used to boost the level of analog line level inputs in a pinch, but it’s
much better to boost the signal level before the A/D converters in order to get maximum
resolution and signal-to-noise ratio from the converters.
The phase invert switch inverts the polarity of the signal. It is generally used to correct
for balanced lines and mics that are wired backwards.