Meequalizer; Output Stage - Joemeek TwinQ User Manual

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Meequalizer

The twinQ "Meequalizer" is a highly effective, versatile and musically
rewarding three-band equalizer, or tone control system. Each stage allows
boost or cut of up to 15dB around the frequency in question. The "EQ"
switch turns the equalizer on, and the green LED lights when active.
The LF band can be tuned or "swept" anywhere between 40Hz and 650Hz.
This effectively covers the whole range of low frequencies. It may help to
think of it as like a graphic equalizer, only instead of lots of frequency bands,
you have just one, but it can be moved to cover any given frequency band.
Cutting can be used to reduce unwanted LF noise, such as hum or rumble.
Boosting can bring out the warmth and body of bass lines and (especially
around 80Hz) kick drums.
The Mid band can be tuned or "swept" anywhere between 300Hz and
5kHz. This effectively covers the whole range of mid frequencies. Cutting
the Mid can reduce sibilance, boominess or other annoying resonances.
Boosting can bring out the body of a vocal, or the harmonics of instruments.
Increasing or reducing the "presence" of an instrument or vocal in this way,
can appear to move the sound forwards or backwards in a mix.
The HF or treble section is centred at either 6 kHz or 12kHz. Boosting the
12kHz band gives a sense of "air" or "sparkle" to vocals, instruments and
mixes, without boosting harsh upper-mid frequencies. Alternatively with
bass instruments, cutting this band will reduce HF noise such as hiss and
crackle. The 6kHz setting is very effective at controlling sibilance and
reducing harshness, or indeed creating it, for example by boosting the
harmonics of electric guitars.
The Meequalizer is after the Preamplifier, the Insert Point and the
Compressor.
plug in a mono jack plug. Either way, this increases the gain of the "+" signal
by 6dB, so there is no drop in level compared with balanced gear.
All outputs on all NextGen Joemeek products are properly balanced, which
is to say there is a signal on both pins! In this way the maximum possible
common-mode rejection of interference, can be achieved at the receiving end.
'COMP LINK'
This is important when both channels of the twinQ are used together for
stereo work. When two mono compressors are used for stereo, differing
amounts of gain reduction occur in each channel, which causes the stereo
image to wander. The "Comp Link" switch avoids this problem by summing
the compressor control paths and slaving control of Channel 2's gain cell
to Channel 1. The "Compress", "Attack" and "Release" on Channel 1 then
operate both channels and the corresponding Channel 2 controls are
redundant. Note however that all other controls still operate independently
on both channels and must be set the same for correct stereo balance. The
LED lights when active.
METER
The analogue meter displays one of three things, depending on the setting
of the "METER" switches.
In VU mode (GR switch out), the Meter shows signal level at the outputs,
after the Output Gain fader. Note that this is relative to the selected operating
level of "+4dBu" or "-10dBv". In other words if you have selected "+4dBu"
and the meter reads "0", then you have +4dBu coming out of the 1/4" jack
output socket. If you have selected "-10dBv" and the meter reads "0", then
you have -10dBv coming out of the output jack.
In Gain Reduction mode (GR switch in), the Meter changes to read "0"dB,
when no signal is present. Whenever the compressor reduces the gain of
a signal, the meter then moves "backwards" to show the amount of gain
reduction taking place at any moment. Note that unlike many other products,
in the twinQ this reading is a true measurement of gain reduction, derived
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by comparing the input and output of the PhotoOptical gain cell.
Technical stuff
Each section of the Meequalizer has a peaking or "bell" shaped
frequency response, which will be found to be musically more
satisfying than conventional "shelving" equalizers. The use of bell
curves at LF and HF also avoids boosting subsonics and ultrasonics
which can have adverse effects on other studio equipment, such as
recorders, monitor amplifiers and speakers. The "Q" value of the
peaking filters is 1.9 (or 1 and 2/3 octaves). Zero phase distortion
ensures the best possible audio coherence.

Output Stage

OUTPUT GAIN
This output volume control provides up to 10dB of gain and also
goes right down to nothing, so acting as a fader to fade a sound
out completely.
CONNECTORS
Two outputs are provided, jack and XLR, so you can simultaneously
feed (say) a recorder and a monitor amplifier. The switch adjacent to
the 1/4" jack selects the output operating level to either +4dBu (suits
most professional studio equipment) or -10dBv (suits semi-pro or hi-fi
equipment). The XLR output is always +4dBu. Check with the hand-
book for whatever you are feeding, to find out which level is required.
The XLR output is balanced
and wired as follows:
Pin 2: + (hot)
Pin 3: - (cold)
Pin 1: ground
Balanced or Unbalanced
To run the XLR output unbalanced, it will be necessary to ground pin
3 of the cable connector. To run the 1/4" jack output unbalanced, just
The third mode "PRE" allows the output of the preamp to be metered
directly, rather like the "PFL" button on a mixing console. This is useful
for adjusting the gain of the Preamp. The momentary 'PRE' switch
overrides both 'VU' and 'GR' metering.
DIGITAL INTERFACE
The Joemeek Digital Audio Interface provides high quality digital audio
outputs plus the ability to synchronize to an external word clock. The
digital audio outputs are compatible with most digital recorders, as well
as Digital Audio Workstations and mixers. S/PDIF format is available
from the optical and RCA phono connectors, while the transformer
coupled XLR connector provides an AES3 compatible output.
The Joemeek Digital Interface has highly stable onboard master clocks
for low-jitter, hi-fi results. Internal sample rates of 44.1kHz, 48kHz,
88.2kHz or 96kHz are selected by means of rear panel switches.
44.1kHz is the standard used for audio CD's, while 48kHz and 96kHz
are widely used in recording studios. In general, the higher the sample
rate, the better the audio fidelity, but the more disk space is required
for the recording. For example, recording at 96kHz requires twice as
much storage as 48kHz. Consult the manual of your recorder or DAW
as to what sample rates it will accommodate.
Alternatively the twinQ may be set to the frequency of an external
master word clock, generated, for example, by the studio's recorder or
DAW. When connected to the BNC socket provided, a suitable external
word clock will be detected automatically and will override the twinQ's
internal word clock. The front panel LED labelled 'EXT CLK' illuminates
when the twinQ is successfully locked to an external word clock.
To avoid distortion, care should be taken not to overdrive the input to
the Digital Interface. The red LED next to the Output Gain control is
labeled "PEAK FSD" which stands for "Full Scale Digital". Occasional
flashes are OK but if it is on all the time, turn something down!
The jack output is balanced
and wired as follows:
Tip: + (hot)
Ring: - (cold)
Sleeve: ground