Zahl IM1 User manual

IM1 M/S INSERT MASTER
IM1 Preliminary Manual 10.2017 www.zaehl.com Page 1 of 7
...another AM1 spin-off in the 500 series format
AM1 is our state-of-the-art pure analog mixing console delivering superb sound quality and comprehensive func-
tionality.
IM1 packs the functionality of the AM1 INSERT and STEREO stages and several added controls into a 2-slot 500
series module.
TYPICAL APPLICATIONS AND BENEFITS
IM1 provides extended options when inserting out-
board analog signal processors into your audio chain
for post-processing, mastering, mixing or recording -
whether in an analog or digital environment (with
ADDA conversion).
In mid/side or conventional left/right stereo modes it
offers control over gain, drive, impedance, stereo
image and dry/wet balance for parallel processing at
high end sound quality.
FEATURES
•
Switchable stereo INSERT with optional MID/SIDE
mode
• SEND BOOST up to +20 dB
• DRY/WET RETURN RATIO control
• Selectable impedance on RETURN (600R, 2k, line)
•
STEREO BASE (width) control switchable between
MID/SIDE and CONSTANT MID mode
• GAIN (±10 dB) and L/R BALANCE (±2.5 dB) com-
pensation on INPUT and OUTPUT
• SIGNAL/OVERLOAD meter LEDs at INPUT and
OUTPUT
• MONITORING of SEND and RETURN signals
•
BYPASS
CONNECTIONS
IM1 is a 2-slot 500 series module with stereo input, stereo output and stereo
insert send and return.
When installed in a Zähl Rack500 a dedicated rear panel provides all connec-
tions (8 XLR connectors).
As the 500 series standard provides only one balanced I/O per slot, the en-
closed additional breakout panel with 4 XLR connectors is needed to operate
IM1 in a standard 500 series rack - requiring one additional slot. Please read
installation guide below.

IM1 M/S INSERT MASTER
IM1 Preliminary Manual 10.2017 www.zaehl.com Page 2 of 7
DELIVERY CONTENTS
• IM1 M/S Insert Master 500 series module (2-slot)
• Plastic bag with insert breakout panel (with 4 XLR connectors) and ribbon cable
• This user manual
• Extracting tool (knurled head screw with M3 thread)
• 1 spare countersunk screw for extracting tool fixture (black, M3x8)
• 6 spare countersunk screws for rack mounting (silver, UNC 4-40 3/8)
• 6 spare countersunk screws for rack mounting (black, M3x6 for metric racks only)
WARNINGS
• IM1 must not be operated in environmental temperatures above 40°C or below 5°C.
Since 500 series racks can differ a lot in how they are constructed and ventilated, you just have to keep an eye
on the temperature inside the rack while in operation.
• Operating a unit beyond the limits can cause severe damage.
• Never insert or remove IM1 while rack is powered - it may cause damage to IM1 and to the rack.
Installation in a Zähl Rack500 equipped with IM1 rear panel
• Unpack IM1. (You do not need the bag with the breakout panel.)
• Make sure the power has been switched off or the mains cable has been removed.
• Carefully insert IM1 into the rack. Keep the unit well aligned until the connectors meet their counterparts.
• Firmly push IM1 into place without using excessive force.
• Mount the IM1 front panel with four screws supplied with your rack.
Installation in a standard API 500 series rack
• You need three slots: two for IM1 and one for the breakout panel adjoining IM1 to the
right.
• Unpack IM1.
• On the rear side of IM1 locate the two Philips head screws which hold a plastic cover on
top of a 14pole connector. Unscrew the cover and put it aside.

IM1 M/S INSERT MASTER
IM1 Preliminary Manual 10.2017 www.zaehl.com Page 3 of 7
• Unpack the breakout panel.
• Plug one end of the enclosed ribbon cable into the mating connector at the
rear of IM1 which you have uncovered before. It only fits one way. It may be
necessary to pull back the isolation sleeve of the cable slightly in order to
plug in the connector.
• Put the plastic cover back into place using the two Philips head screws. Make
sure to mount it the right way around: The sharp-edged side with the crack
marks must not face the cable!
• Make sure the power of your rack has been switched off!
• Carefully insert IM1 into the rack. Make sure the ribbon cable faces to the
right. Keep the unit well aligned until the board edge connectors meet their
counterparts.
• Firmly push IM1 into place without using excessive force.
• Make the ribbon cable stick out of the free slot to the right of your IM1.
• Fix the IM1 front panel with four screws that come with your rack or
our enclosed spare screws.
• Plug the free ribbon cable connector into the mating PCB connector
on the breakout panel. It only fits one way. It might be necessary to
move the strain-relief levers of the PCB connector outwards in order
to insert the connector. When the connector is firmly plugged in the
strain-relief levers should automatically snap back into place and
prevent unintentional release.
• Mount the breakout panel with two screws that come with your rack
or our enclosed spare screws.
Extracting Tool
In order to remove IM1 from the 500 series rack we recommend using the enclosed
extracting tool. Remove the M3 Philips head countersunk screw in the INSERT section
on the front panel. In place of this screw, screw in the extracting tool gently without
tightening it.
Then hold by the tool and carefully pull straight out - do not apply any force sideways!
When done, do not forget to put the M3 countersunk screw back into place.

IM1 M/S INSERT MASTER
IM1 Preliminary Manual 10.2017 www.zaehl.com Page 4 of 7
OPERATION
I/O Stages
• Dedicated INPUT and OUTPUT level setting
−
GAIN ±10 dB
−
L/R BALANCE ±2.5dB
• Dedicated INPUT and OUTPUT level metering
− SIGNAL (LED green): level present
− O/L (LED red): overload warning reading multi-
ple points in the signal chain
• BYPASS switch
INSERT
• INSERT on/off switch inserts the connected sig-
nal processors into the signal chain. (An internal
jumper can be set to mute INSERT SEND when
INSERT off, or to keep INSERT SEND always active,
jumper setting see below.)
• MID/SIDE Switch encodes the INSERT SEND ste-
reo signal from left/right to MID/SIDE and de-
codes the RETURN signal back from MID/SIDE in-
to left/right. The normally left channel carries the
MID signal (sum L+R) and the normally right
channel the SIDE signal (difference L-R). Individu-
al processing of MID and SIDE signals can be a
powerful technique to be used in mastering, in a
mix sum or in creative sound processing.
• SEND BOOST control adds gain of up to +20 dB to the INSERT SEND output. This allows you to drive your out-
board gear to where it sounds best - especially useful for vintage/tube/transformer equipment.
• Z switch offers selection of impedance on INSERT RETURN: LINE (>20 kΩ), 2 kΩor 600 Ω. Impedance matching
affects the sound and is in some cases essential. With this switch you will easily find the best match.
• DRY/WET RETURN RATIO control balances between original signal (DRY) and processed signal (WET) at IN-
SERT RETURN - also called parallel processing. This can be used for example to add a small amount of heavy
processing while maintaining the overall integrity of the original signal - especially transients.
• MONITORING matrix with four switches allows you to check what is being sent to your inserted equipment
and what is coming back - especially helpful in MID/SIDE mode. Push any button to set the unit to MONITOR-
ING mode. You can select INSERT SEND or RETURN for L/MID channel and for R/SIDE channel individually.
LEDs next to each switch indicate what is being monitored. Push again to return to normal operation. Monitor
signal is send to the main outputs.

IM1 M/S INSERT MASTER
IM1 Preliminary Manual 10.2017 www.zaehl.com Page 5 of 7
STEREO BASE
This stage is based on MID/SIDE technology and can
widen or reduce the stereo image.
• STEREO BASE on/off switch
• STEREO BASE potentiometer: In center position the
signal is unaffected - normal STEREO. Turned to-
wards MONO it reduces the stereo image. Turned
towards DIFF it fades out the MONO portion and en-
hances the STEREO portion by 6 dB. The fader re-
sponse is optimised for live use in a mix by compen-
sating the typical output level increase when turning
from STEREO to MONO.
• CONSTANT MID function keeps the MONO portion constant, thus avoiding loss of lower frequency content
(due to phase cancellation) when the control is set past the STEREO (center) position clockwise towards the
DIFF position. In the DIFF position (fully clockwise) the STEREO portion is enhanced by 6dB, resulting in a “su-
pernatural” stereo image.
INSERT SEND JUMPER
By default the INSERT SEND output remains active when INSERT is switched
off. The INSERT on/off switch only affects the INSERT RETURN in this setting.
This behaviour can be changed via an internal jumper as shown below. In
this optional setting the INSERT on/off switch also mutes the INSERT SEND
output.
Standard:
INSERT SEND output is always
active
Optional:
INSERT SEND output is muted
when INSERT is switched off

IM1 M/S INSERT MASTER
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IM1 M/S INSERT MASTER
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NOTES, SAFETY INSTRUCTIONS, WARRANTY
1. The equipment must only be used for the purpose described in this manual.
2.
Keep the manual for further reference. When passing the equipment on, enclose the manual.
3.
Do not operate the equipment at
- very high air humidity (>85% relative humidity)
- high environmental temperature (>40°C) or near heat radiating equipment or objects
- places which are exposed to solar radiation
- very low temperatures (<5°C)
4.
Ensure appropriate air ventilation.
5.
Do not store the equipment at temperatures below -20°C or above +50°C.
6.
Do never expose the equipment to environmental conditions which can lead to water condensation.
7.
Do not expose the equipment to mechanical stress or shock.
8.
Ensure that liquids cannot get into the equipment.
9.
Ensure that foreign objects cannot get into the equipment.
10.
Only operate the equipment on a safe, legally approved, mains power supply
11.
Only clean the equipment with smooth cleaning tissues and soft detergents.
12.
Never open the equipment.
13.
In case the equipment has been dropped or there is any external or functional damage, do not continue to
operate the equipment. Have the equipment checked at your dealer’s workshop or a person who is qualified
to do such checks.
14.
When shipping, use a package which protects the equipment from environmental impact such as mechanical
shock or humidity.
15.
The equipment applies to EU directives RoHS and WEEE. Dispose separately according to WEEE. Manufacturer
WEEE register number: DE 90586269
16.
Manufacturer’s warranty covers the equipment to be free from defects of quality at the time of delivery for a
period of 24 month presumed that
- the equipment was treated properly according to its intended use
- all information and safety instructions given in this manual have been followed
- the equipment shows no external damage
- the equipment is shipped to the manufacturer or to an authorised repair-shop free of charge
- a proof of purchase is supplied
- a detailed failure description is supplied
The manufacturer accepts the costs of parts and labour incurred by repair. Any other costs including ship-
ping and packaging will be charged.
17. We expressly exclude any liability for incidental or consequential damages which might arise from operating
the equipment, including failure of the equipment.
18.
All information in this manual has been carefully reviewed. It has been updated at the time of passing for
press. Nevertheless we do not accept any liability for insufficiency or errors.
19.
EEC Declaration of Conformity: The equipment applies to applicable EMC rules 2004/108/EEC.