M2TECH JOPLIN MKII, Руководство пользователя

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JOPLIN M
K
II
384
k
H
z
/32bit ANALOG-TO-DIGITAL CONVERTER
REVISION P
R
A – FEBRUARY 2015
Copyright © 2015, M2Tech Srl
49
M2Tech
www.m2tech.biz
8.3.6. Display dimming
The
JOPLIN MKII
display intensity can be set on 5 different levels. In addition, an
automatic dim mode allows for keeping the display off every time it’s not necessary to
read it. When the automatic mode (value “A”) is chosen, the display activates at the
highest intensity every time a control is accessed, then it remains active for 5
seconds after the last control is accessed, finally turning off.
8.3.7. High pass (anti-rumble) filter
When acquiring a noisy source, it is sometimes desirable to cut some low
frequencies. For example, warped records or the output of a mike preamp or a mixer
when recording live in a windy setup. Two high-pass cut-off frequencies are
available: 16Hz (for microgroove LP’s and also for modern era stereo LP recorded
with RIAA curve when the extra 16Hz high pass is known to be used for the LP
making) and 50Hz (for most 78rpm records which have generally poor music
contents below 50Hz). See Figure 20 for more details on high-pass filter effect on
frequency response.
8.3.8. Low pass (anti-hiss) filter
When acquiring a noisy source, it is sometimes desirable to cut some high
frequencies. For example, many 78rpm records have poor music contents above
5kHz and a strong surface noise. Using a low-pass filter allows for a more intelligible
sound. Two low-pass cut-off frequencies are available: 5kHz and 10kHz. See Figure
20 for more details on low-pass filter effect on frequency response.