TC Electronic SYSTEM 6000 MKII Algorithm Manual - Massenburg Eq
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MAssEnburG EQ
Introduction
More than one flavor of EQ
In recognition of George Massenburg’s great sense of
audio and strong influence on previous TC processors, the
new MDW HiRes EQ is offered as an licensed algorithm
option. The MDW design complements the TC alternatives
and therefore offers the user a choice between several
desirable EQ flavors, each with specific advantages. All of
them have processing capabilities worthy of handling any
critical signalpath.
System 6000 and MDW HiRes EQ
The combination System 6000/MDW HiRes EQ constitutes
a 48 bit precision signal path from Input to Output. It comes
in 2 and 6 channel configurations with flexible linking and
absolute/relative realtime adjustment properties. The 6
channel version features 6 identical processing channels
making it equally suitable for controlling 5.1 and 6.0
signals.
Quality equalization is not only a question of a fine filter
design with high bit resolution. Precision in timing is just as
important, as is conversion from Analog to Digital and vice
versa. The high resolution routing, extremely low jitter and
pristine conversion environment provided by System 6000
bring out the best qualities in George’s digital EQ design.
Sample Rate
If the System rate is set at 44.1 or 48kHz, the signal is
up-sampled to double rate, processed and down-sampled
to System rate. This approach is one way of mimicking
more precisely the behavior of analog EQs plus reducing
alias distortion.
The EQ can also be operated at 88.2 or 96kHz. At high
System rates, up/down sampling is bypassed, providing a
bit transparent signalpath at unity gain.
Bands and Filters
The EQs feature 5 parametric bands per channel. Outer
bands can be configured as shelving or 2nd order filters
(Butterworth). Band 1 filters can be switched between 2nd
and 4th order.
All five bands cover the complete frequency range. Each
parametric or shelving band is capable of cut/boost over a
+/-25 dB range.
Channel Linking and operational Hints
In the 2 channel version, equalization of stereo material
should initially be performed in Absolute link mode, i.e.
changes applied to Left channel will also be applied to
Right. If it is indicated to make different adjustments
to L and R, the link is released until the desired
differences have been established. Now a Relative
link can be enabled, preserving the adjustment off-sets
between channels, but not having to adjust both of them
permanently.
In the 6 channel version, up to three different Absolute
links may be set. Before link channels can be changed,
the Link Enable key has to be active. When a link is
established, the settings of the lowest channel number
in the group will be copied to the rest. The settings of all
channels in a link group will remain the same as long as
the channels are linked. When the desired number of links
have been established, it is advisable to turn off the Link
Enable function to prevent against accidental editing and
copying. Linking of all channels may serve as a quick way
to achieve an identical initial setting of all channels.
Latency
At 44.1 and 48kHz sampling, delay (latency) is 37 samples,
which equals 0.84 ms at 44.1kHz and 0.77 ms at 48kHz.
At 88.2 and 96kHz sampling, delay (latency) is 10 samples,
which equals 0.11 ms at 88.2kHz and 0.10 ms at 96kHz.
Notes
Because of the upsampling approach, latency is higher
at low rates. As a reference to the real world, it’s useful
to remember that 1 ms of delay equals one foot of extra
distance between source and microphone. 3 ms of delay
equals one meter of extra distance between source and
microphone.
The MDW Hi Res EQ 2 channel algorithm occupies:
@ Normal Sample Rate : 1/4 DSP Resource
@ Double Sample Rate : 1/4 DSP Resource
Algorithm Inputs/Outputs are distributed as follows:
E1 - E4
L
R
L
R
INPUT
OUTPUT
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The MDW Hi Res EQ 6 channel algorithm occupies:
@ Normal Sample Rate : 3/4 DSP Resource
@ Double Sample Rate : 3/4 DSP Resource
Algorithm Inputs/Outputs are distributed as follows:
E1 - E4
1
2
3
4
5
6
1
2
3
4
5
6
INPUT
OUTPUT
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