4ms Dual Looping Delay, Руководство пользователя

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Concepts
On the back page of this manual is a block diagram of the control and signal paths for one channel. The metaphor is that
each DLD channel is a tape loop, with a separate read and write head, and the ability to move each heads to a new location.
The tape is assumed to move at a constant speed (constant sample rate), but can be reversed in direction. The magic ability
to change the length of the tape loop is also assumed in this metaphor (Infinite Hold mode).
Ping: Setting the beat
The DLD requires a base time, which is referred to as a “ beat ” in this manual. Each channel can have a different delay or loop
time, but both channels' delay/loop time will be mathematically related to the length of one beat. If you are familiar with other
4ms modules, you may be familiar with the concept of “Ping”. In the DLD, the
beat is the Ping.
There are several ways to establish the beat:
• Tap the Ping button twice. One beat will equal the time between your taps.
•
Patch an external clock into the Ping jack . One beat will equal the time between the last two
pulses.
• Just turn on the DLD and do nothing more! The DLD automatically boots up at around 150BPM
• There is a fourth way of setting the timing, which is by enabling Clock Bus support on your DLD and using a Clock
Bus master such as the QCD to send the clock over the power distribution board. See the
Clock Bus Jumper section.
The DLD's clock is extremely stable and jitter-free. It's highly recommended to use the internal DLD clock (tap clock) if
possible, because it's quantized to the sample clock and has less jitter than most common commercially available clock
sources. Using the DLD as a master clock will provide the tightest timing possible in a patch with the DLD. However, if it's not
possible to use the DLD as a master clock, you can sync to an external clock by patching it into the Ping jack. The DLD will
quantize the external clock to its own sample rate and output quantized clocks on the two Loop jacks. If there is any jitter or
drift in the external clock, the DLD will track and follow these discontinuities, which can result in interesting (or noisy! artifacts).
Channels
There are two channels: A and B. Each channel has a separate audio path, controls, and CV/trigger jacks. The channels are
identical — except for the fact that the inputs and outputs automatically connect together if nothing is patched into Channel B
(see below). Both channels share a common time base, or
beat , which is set by the Ping button or jack. Each channel can
multiply, divide, or add to the base time by using the Time knob, switch, and CV. Anytime the base time is changed (by
tapping the Ping button, or changing the external clock), both channels will instantly change tempo while maintaining the
same ratio to each other.
Channel normalizations
The main In A jack feeds into the switch tab of the main In B jack. Therefore, plugging into the In A jack will run
the audio signal to Channel B as well. If you plug a cable into the In B jack, then the normalization will be
disabled. The “-->B” graphic on the panel near the In A jack reminds you of this normalization.
Similarly, The switch tab of the Out B jack feeds into the signal tab of the Out A jack. Therefore, if nothing is
plugged into the Out B jack, then the output from channel B will be mixed with the output of channel A and
appear on the Out A jack. The “<--B” graphic on the panel near the Out A jack reminds you of this normalization.
To use the DLD as a two-channel delay in parallel, plug into the In A and Out A jacks. Both delay channels will
operate in parallel, mixing together into the Out A jack.
To use the DLD as a one channel delay, plug into the In B and Out B jacks. Channel A will not be used. Alternatively, patch
into In A and Out A , and patch a dummy cable into Out B to disable the normalization.
To use the DLD as a two channel series (cascading) delay, plug into the In A jack, and patch from Out A to In B , and then
take the output from Out B . Alternatively you can patch from Send A to In B or Return B . See the Using Send and Return
discussion in the Applications section below.
Time
The Time parameter sets the length of the loop, or amount of delay time. This period of time is
relative to a
beat , which is set by tapping the Ping button or patching an external clock into the Ping
jack.
The Time knob, CV jack, and switch perform simple arithmetic on the beat time to produce a
delay/loop time.
• Time Switch center (=): the Time knob directly sets the number of beats for the loop or delay time. Example: if you
turn Time to “5”, the channel will make an echo (or loop) every 5 beats.
• Time Switch up (+16): 16 is added to the whatever the Time knob shows.
Example: if the Time knob is pointing to 5, the channel's delay or loop time will be 5 + 16 = 21 beats.
• Time Switch down (1/8): the Time knob is divided by 8, making the delay/loop time 8 times as fast (eighth notes).
Example: Time knob is at 5, the channel will echo in 5/8 th notes, or eight loops for every five beats.
Using CV will modify the Time knob's setting by multiplying or dividing the knob's value. Positive CV makes the delay time
longer, negative CV makes it shorter.
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