LP2 usage guide

[andy butler <akbutler@tiscali.co.uk>]

Here's the docs for the LP2, gleaned from the Looperlative Blog.

((additionally))
It doesn't say here,
but the LP2 has a Rec/Dub button and a Play/Stop button.
Presumably those work in the same way as the buttons on a DL4
(which is what the LP1 does too).





Getting Started
Before turning on the LP2, you must insert an SDHC storage card. It is 
recommended that you use a
SanDisk Ultra or Ultra II SDHC card of at 4GB in size. It is recommended 
that you only change
storage cards with the LP2 powered off.
The LP2 requires 9V power. This can be either 9V battery or a 9V 
negative-center pedal power supply
which is commonly used by many music pedals (don't worry about current 
rating).
To power the LP2 with a battery, remove one of the
side panels and slide the bottom out of the way. When a battery is 
installed, the LP2 will only power
on when the audio input cable is connected.
Connect the audio input and audio output. These are mono 1/4” 
connectors. Now you are ready to
adjust the mix level. The mix knob on the back panel adjusts the amount 
of dry signal passes
unchanged from the input to the output. You should be able to hear your 
audio signal pass from input
to output. Now you are ready to adjust input volume to the recording 
portion of the LP2.

Proceed to
Setup Mode.

Important Notes
Using the SDHC card for audio storage results in a few rules about 
recording and overdubbing.

1.There is a minimum loop length. It is approximately 1 second, but that 
gets longer if you record
in ½ SPEED or ¼ SPEED mode. In ¼ SPEED mode, the shortest loop that you 
can record is
about 4 seconds long.

2.When you start an overdub, a new undo layer is created. The LP2 must 
completely record the
new layer. If you overdub less than the length of the loop, then LP2 
will flash both status LEDs
to indicate that it is still copying the remaining loop audio to the new 
layer.

3.The audio is not stored on the SDHC card in a computer readable 
format. It is not
recommended that you put the SDHC card in a computer SD card reader.

4.Not all SDHC cards are fast enough to keep up with the audio 
recording. If the card fails to
record fast enough, recording will end and not play back.

Setup Mode
On the back is a configuration button, if you press the button for 
approximately 2 seconds, the LP2 will
switch to setup mode. When the LP2 goes to setup mode, the green and red 
status lights will alternate.
The 8 red effect LEDs will act as a sound level meter in this mode. When 
performing, you would like
audio to light 7 of the effect LEDs. If the sound level is too low, then 
fewer LEDs will light up. It is
best to adjust the audio level from the audio source, but if that isn't 
possible, the LP2 offers 3 different
input gains. You can switch between input gain levels by pressing the 
PLAY button when in Setup
Mode.
Pressing the RECORD button will exit Setup Mode.



Status LEDs
The red and green status LEDs indicate the current mode. These modes are 
listed here:


The status LEDs flash alternating between red and green to indicate 
Setup Mode.
A solid red LED indicates that the loop is recorded by stopped.
A solid green LED indicates that the loop is playing.
A blinking red LED indicates that you are recording a loop.
A blinking green LED indicates that you are overdubbing.
If red and green are flashing together, then an overdub layer is being 
completed.
If red and green are both on solid, then the LP2 is in song selection 
mode.



Configuration Mode
Configuration Mode allows you to select assignments to the two Effect 
buttons, activate the undo
function, or select a different song.

There are two ways to enter configuration mode: press the
configuration button on the back or hold the RECORD button when in Play 
Mode. When
Configuration Mode is first entered, all 8 of the effect LEDs will flash 
together.

Undo
Enter Configuration Mode, then press the RECORD button while all 8 
effect LEDs are flashing. This
will undo the last overdub.

Song Select
Enter Configuration Mode, then press the PLAY button while all 8 effect 
LEDs are flashing. The
EFFECT buttons can then be used to change to one of eight different 
songs that you have recorded or
will record. The effect LEDs will indicate which song will be chosen. 
The LP2 will not switch to the
new song until the PLAY button is pressed to end the mode.
You can cancel the mode without selecting a new song by pressing the 
RECORD button.
Effect Button Select
In Configuration Mode, pressing the Effect buttons will first show what 
that button is set to and then if
pressed again will be switched to the next choice.
Press the RECORD button to exit this mode.
The Effect 1 button can be assigned one of the following functions:
RETRIGGER ONCE(restart at beginning of loop and stop at end, like DL4)
RETRIGGER RANDOM
½ SPEED
REPLACE
REPLACE 1/8
REPLACE 1/12
REPLACE 1/7
REPLACE 1/10

The Effect 2 button can be assigned one of the following functions:
CONTINUE(Play loop starting from where you stopped)
RETRIGGER CONTINUOUS(restart at beginning of loop...and keep on playing)
¼ SPEED
REVERSE
REPLACE 1/16
REPLACE 1/24
REPLACE 1/9
REPLACE 1/64

The Effect LEDs During Play Mode
Certain Effect LEDs will light or blink during Play Mode to indicate 
conditions. These are:
The LED next to REPLACE 1/10 flashes at the beginning of the loop.
The LED next to REPLACE 1/7 turns on when MIDI clock input is detected.
The LED next to REVERSE is on when the loop is playing in reverse.
The LED between ½ SPEED and ¼ SPEED is on when either of those 2 speeds 
are selected.
The LED next to RETRIGGER RANDOM is on when ¼ SPEED is selected.


MIDI clock
The LP2 provides MIDI clock message on the MIDI out port whenever a loop 
is playing. The MIDI
clock out assumes that the loop is one measure and that you are in 4/4 
timing.

The LP2 will synchronize to a MIDI clock on the MIDI in port when you 
record a new loop with MIDI
present. The MIDI clock input assumes 4/4 timing coming in.


Audio
The LP2 uses an LM4550 Audio CODEC for audio input and output. This 
CODEC provides 16-bit
samples to the processor in the LP2. The LP2 then reduces the samples to 
12-bits for storage to the
SDHC card. The sampling rate is 44.1 kHz.


Partial schematics of the LP2 detailing the audio electronics will be 
made available in the future.