Crane Song SPIDER - Manual (Page 4)

When the STEREO BUS ASSIGNMENT SWITCH is pushed in the channel is assigned to the stereo
bus. When the switch is out the channel is not assigned to the bus. The channel outputs are always
assigned to the 8 channel outputs.
The FAT AMPLIFIER is enabled when the switch is active (pressed in). The fat amplifier is used to
provide a different sound by inducing tube like distortions. This distortion content is almost all second
harmonic with some third harmonic. The level of distortion is such that it reaches 6.5% at digital zero. It is
0.3% at +4dbm at the analog output which is 20 dB below digital zero.
The LEVEL METER is a 16-segment peak reading meter and is referenced to the A/D convertor. Ana-
log head room is such that there is 6 db of analog head room above the level that is digital zero. This is
to allow up to 6db of limiting before the A/D convertor. An “over” on the meter is a digital over, but not
necessarily an indicator of analog clipping. (There is 6db of analog headroom above digital 0 with out
the limiter engaged) There is also a clip indicator on each channel. This is a small red light in the upper
left hand corner of the channel. This indicator shows an input or pre-amp overload. The level meter is an
analog device that is feed from the A/D convertor input.
The LIMITER is for peak overload protection and is in front of the A/D convertor in the signal path. The
level meter is post limiter. There is an indicator on the channel next to the limiter button that lights when-
ever limiter action is taking place. The limiter is enabled by pushing the LMT button down. The signal
structure is such that the input channel can provide 6 dB more level that the A/D convertor needs. This
headroom is for the operation of the peak limiter. The limiter will bring the level down thus protecting the
A/D convertor from overload.
The ANALOG INSERT POINT is a 1/4" phone jack and is wired as tip send and ring return. This insert
point is unbalanced and has a maximum signal level of +24 dbm.
8 CHANNEL DIGITAL SECTION
The SAMPLE RATE SELECTION SWITCH allows the selection of 1 of 4 sample rates from 44.1K to
96K or the selection of a word clock source. The WC source is the same for both the stereo and 8
channel sections.
The STEREO BUS can be assigned to digital channels 7 and 8. This is to allow a mix to be recorded by
a recorder on channels 7&8 of the 8 channel output. The assignment takes place by pushing the “bus
7&8” switch in. When this is done the normal connections from input channels 7 and 8 are disconnected.
The limiter on the digital stereo module is still used to prevent digital overload on the bus signal.
The DITHER CONTROL provides dithering to different bit levels. This source is unique to CRANE
SONG and is generated by analog means. The audio signal and the dither source are mixed together
going into the A/D convertor. This is the best place to create dithering. The switch has many selections.
There are 16 and 20 bit choices and some options for play and experimentation.
DSP ANALOG TAPE EMULATION is adjustable by channel. The tape emulation feature provides a
means to have analog tape sound in Spider’s digital outputs. By selecting the channel, the LEDs around
the process knob will light showing the current level of the process
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