LOOPTROTTER SATUR-8/24 User manual
LOOPTROTTER
AUDIO ENGINEERING
24-channel Summing mixer
with
8 channel saturation modules
OWNER'S MANUAL
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
Table Of Contents
1. Introduction
2. Installation
3. Signal Path
4. Controls - Front Panel
5. Application examples
Introduction
Thank you for choosing Looptrotter SATUR-8/24. This device can be used as
8 independent saturation modules, applied either during recording or
mixing. SATUR-8/24 is also a 24-channel summing unit. Thanks to the
independent control of the main output and monitoring, it can be utilized
as a monitor controller in your studio.
The saturation modules resemble the sound of old tube mixing consoles and
tape recorders. However they are built entirely with the use of
semiconductor technology, which guarantees endurance and reliability.
The summing module is an original combination of active summing, run by
operational amplifiers and passive summing based on transformers. The
mixed signal is amplified by a transistor preaplifier operating in pure
class A, built of discrete elements, inspired by the early designs of
transistor preamps from the 60's. Additionally the summing circuit is
fitted with a “Magic” module, which magically nears, widens and thickens
the whole mix, giving it a vivid, analog sound.
Installation
Looptrotter SATUR-8/24 is set by default to match the mains power voltage
in a given country. Check the settings on the rear panel.
The incoming signal is inputted with the DB-25 multi pin connectors in
Tascam standard.
LOOPTROTTER
AUDIO ENGINEERING
H = HOT +
C = COLD -
G = GROUND
8 7 6 5 4 3 2 1910111213
141516171819202122232425
G C H G C H G G C H G G G C H G C H
1 2 3 4 5 6 7 8
C H C H C H
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
MAIN and MONITOR outputs are balanced XLR.
INSERT inputs and outputs are balanced Jack TRS.
LOOPTROTTER
AUDIO ENGINEERING
Signal path
SATUR-8/24 has 24 input channels. Signal incoming to channels 1-8
flows directly on 8 saturation circuits. Signal incoming to channels
9-24 inputs directly the summing bus. Channels with odd numbers (9-
23) are assigned to the left channel. Channels with even numbers
(10-24) are assigned to the right channel.
Within the saturation circuits (channels 1-8) the incoming signal enters
the DRIVE potentiometer, next it flows through the preemphasis module,
which decreases the low frequencies level. Following, the signal goes
to the saturation circuit. The saturation level – the amount of added
harmonics – depends directly on the input level, controlled with the
DRIVE knob. After the saturation circuit there is deemphasis module,
which boosts low frequencies, next the processed signal goes through
OUTPUT potentiometer. Having gone through the OUTPUT knob the signal is
split and directed to outputs 1-8 and LCR switches, which allow to pan the
signal.
The signals from channels 1-8, 9-16 and 17-24 are being summed
independently by operational amplifiers (active summing) and then they
go to summing transformers (passive summing). Following the transformers
the signal is amplified with 30dB by transistor amplifiers. Totally
summed signal split into left and right channel flows through the “magic”
circuit. This circuit can be engaged with a switch on the front panel.
There is an option to insert an external device, such as equalizer or
compressor, on the summing bus, via the INSERT connectors on the rear
panel. After the INSERT connectors the signal is split and goes to
potentiometers controlling the MAIN and MONITOR output levels. Two VU
meters on the front panel indicate the signal MAIN OUTPUT levels of the
left and right channel.
XLR:
PIN 1: ground
PIN 2: positive
PIN 3: negative
TRS:
Tip : Hot(+)
Ring : Cold(-) Sleeve
: GND
INPU T
OUTP UT I N SE R T
R RL L
MONI TOR
MAIN OU TPUT
R RL L
1
3
2 1
3
2 1
3
2 1
3
2
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
LOOPTROTTER
AUDIO ENGINEERING
DRIVE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
01
L C R
ON
OFF
DRIVE
OUTPUT
08
L C R
ON
OFF
S A T U R A T I O N
C I R C U I T
T H D
M E T E R
ON
OFF
-81
MIX
MAGIC
NORM.
1
2
3
4
567
8
9
10
11
MONITOR
1
2
3
4
567
8
9
10
11
MAIN
INP UT 9-16 INP UT 17-24
INPU T
OUTP U T I N S E R T
INP UT 1-8
OUT PU T 1- 8
ACTIVE SUMMING
AMPLIFIER
ACTIVE SUMMING
AMPLIFIER
ACTIVE SUMMING
AMPLIFIER
PASSIVE
SUMMING
DISCRETE
AMPLIFIER
MAGIC
CIRCUIT
L R
MAI N O UTP UT
MON IT OR OUT PU T
V U
7
5
3
20
1
0
1
0
2
1
2
3
V U
7
5
3
20
10
1
0
2
1
2
3
1-8 MIX BUS
9-16
MIX
BUS
17-24
MIX
BUS
1-8 ON/OFF
LEFT VU RIGHT VU
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
DRIVE – this knob controls the level of the signal
entering the saturation circuit. Increasing the DRIVE
level results in stronger signal saturation, giving the
ear friendly distortion and audibly higher RMS level,
thus loudness. Note that the saturation level depends
also on the input signal level.
ON/OFF – Turns the saturation module on and off.
With the saturation module engaged the DRIVE and OUTPUT
knobs are inactive.
LED METER – indicates the amount of added
harmonics – the depth of saturation. The orange LED
lights on above the 4% THD, red LED lights on above the 8%
THD. Above 8% THD the signal saturation is clearly
audible.
OUTPUT – this knob controls the level of the signal
leaving the saturation circuit. In position 0 the signal
is muted.
LCR – this switch sets signal panning.
L- left channel; C - central - mono; R – right channel.
The LCR switch acts independently from the saturation
module and is active even when the latter is disengaged.
1-8 - ON/OFF – this switch turns on and off all the
8 saturation channels simultaneously. In the OFF
position the LED flashes red.
MIX - MAGIC/NORMAL –this switch activates the
„MAGIC” module. In NORMAL position the module is
inactive and does not influence the mixed signal.
MONITOR – this knob controls the signal level on
the monitor output.
MAIN – this knob controls the signal level on the
main output. The main output level is indicated by two VU
meters.
LOOPTROTTER
AUDIO ENGINEERING
Controls – Front Panel
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
LOOPTROTTER
AUDIO ENGINEERING
8 x
S A T u r A M P
OUT P U T 1- 8
LOOPTROTTER
AUDIO ENGINEERING
SATUR-8/24 used as 8 independent saturation
modules, applied during recording.
INP U T 1-8
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
0
1
2
3
456
7
8
9
10
GAIN
HPF
INV.48V PAD
OUT
0
18
18
60 100 160
ON 4 8
INSTR.
!
SAT.
LOOPTROTTER
AUDIO ENGINEERING
MUTE
SAT
URA M P
INP U T
OUT P U T I N SER T
R RL L
MON I T OR
MAI N O UTP U T
INP U T 9-16INP U T 17-24
LOOPTROTTER
AUDIO ENGINEERING
R RL L
8 c h . A D C
Contact:
www.looptrotter.com.pl
LOOPTROTTER
AUDIO ENGINEERING
Distribution:
www.mjadiolab.pl
INPUT
OUTPU T I N S ER T
R RL L
MONIT O R
MAIN O U T P U T
INPUT 9 - 16INPUT 17-24 OUTPU T 1 - 8
INPUT 1 - 8
R RL L
LOOPTROTTER
AUDIO ENGINEERING
0
10
20
30
40 50 60
70
80
90
100
TUBE
DUAL
LINK
G.R.
OUT
METER
2nd
ATTACK
RELEASE
CHANNEL 01 CHANNEL 02 ATTACK
RELEASE
1
2
3
4
5
6
9
12
15
18
21
24
FET COMPRESSOR
COMP.
LIMITER
BYPASS
PROCESS
12
9
6
3
0
3
6
9
12
15
18
21
TUBE
2nd
SATURATION
BYPASS
PROCESS
CH. 2
TRUE BYPASS
PROCESS
SATURATION
0
1
2
3
456
7
8
9
10
OUTPUT
1
2
3
4
5
6
9
12
15
18
21
24
INPUT
FET COMPRESSOR
COMP.
LIMITER
BYPASS
PROCESS
POWER
MAIN
5
4
3
2
101
2
3
4
5
MIX
12
9
6
3
0
3
6
9
12
15
18
21
BYPASS
PROCESS
CH. 1
TRUE BYPASS
PROCESS
BOOST BOOST
OUTPUT
dB
%
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10 0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
-
+0
10
20
30
40 50 60
70
80
90
100
MAIN
5
4
3
2
101
2
3
4
5
MIX OUTPUT
dB
%
-
+
.5
15
25
50
70
100 150 .2
.3
1
1.5
ms/sec
.1
.2
.5
1
257
15
30
50
100
ms
OUTPUT
INPUT
.5
15
25
50
70
100 150 .2
.3
1
1.5
ms/sec
.1
.2
.5
1
257
15
30
50
100
ms 24ch.DAC
2ch.ADC
Mixed signal
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
01
ON
OFF
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
02
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
03
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
04
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
05
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
06
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
07
ON
OFF
OUTP UT
0
1
2
3
456
7
8
9
10
08
ON
OFF
DRI VE
0
1
2
3
456
7
8
9
10
-81
POWER
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
01
ON
OFF
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
02
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
03
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
04
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
05
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
06
ON
OFF
DRI VE
OUTP UT
0
1
2
3
456
7
8
9
10
0
1
2
3
456
7
8
9
10
07
ON
OFF
OUTP UT
0
1
2
3
456
7
8
9
10
08
ON
OFF
DRI VE
0
1
2
3
456
7
8
9
10
-81
POWER
LOOPTROTTER
AUDIO ENGINEERING
SATUR-8/24 - used as 24-channel summing mixer.
Channels 1-8 have saturation circuits.
Channels 9-24 are channels without saturation.
In order to expand the number of channels of saturation,
may be used SATUR-8 expander between the DAC and SATUR-8/24.
In the loop's insert can be insert a compressor or EQ.
LOOPTROTTER
AUDIO ENGINEERING
Artist:
Sesion:
Date:
Notes:
.................................................
..................................................
.....................................................
....................................................
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
LOOPTROTTER
AUDIO ENGINEERING
Contact:
www.looptrotter.com.pl
Distribution:
www.mjadiolab.pl
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