HUM RS-2 User manual

RS-2 Stereo Ribbon Recording System _
OWNER'S MANUAL
v1.1 02/2018
The information in this document has been carefully verified and is assumed
to be correct. However HUM Audio Devices reserves the right to modify the product
described in this manual at any time without prior notice.
This document is the property of HUM Audio Devices and may not be copied or
reproduced in any manner, in part or full without the authorisation of HUM Audio
Devices.
Contents
Foreword Introduction .................................................... 2
Operation Safety ............................................................. 3
Service and Repairs .......................................................... 3
Replacement Parts …......................................................... 4
Cleaning …..................................................................... 4
Active and Passive Mode …................................................... 5
Installation and Connections (Active Mode) …............................ 6
Power Supply Unit ….......................................................... 7
Hand Lever Operation …..................................................... 8
Stereo L/R (Blumlein) and M/S modes ….................................. 9
Using Remote Controller ….................................................. 10
Specifications …............................................................... 12
Warranty …..................................................................... 14
Limitations of Liability ….................................................... 15
Contact …...................................................................... 15
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Dear Customer,
Thank you for the confidence you have shown towards HUM Audio Devices
by purchasing the RS-2 Stereo Ribbon Recording System. You have choosed an
unique, high end tool which will help you to get excellent recordings. RS-2 is a
result of over two years of meticulous development, careful audiophile quality
component selection, and extensive studio testing during real sessions to get THAT
sound. Becaue we are also sound engineers with 20 years of practice in recordings,
we did our best to provide RS-2 with all unique features that make it very
practical, creative and extraordinary tool.
We believe you will have much fun using RS-2 and love it as we do.
We wish you every success with your new RS-2 stereo ribbon mic system!
Your HUM Audio Devices – Team
Krzysztof Tonn Krzysztof Rudnicki
Follow us on Youtube, Facebook and our site:
www.hum-audio.com
HUM Audio Devices RS-2 was designed, developed and precisely handcrafted in
Poland.
Introduction
Our RS-2 is world's first remote controlled, Stereo/M-S ribbon microphone
system with built-in High-End discrete class A mic preamps.
RS-2 is complete recording system with sound and features never before
found in any of the top class ribbon mics. Custom tailored 1.8 micron aluminium
ribbon motors are paired together with audiophile quality handcrafted audio
circuits and high precision CNC-machined mechanics.
You will find that RS-2 excels on many sound sources, covering wide range of
studio recording applications, including string section recordings, piano, guitars,
woodwinds, ambience, drum overheads and vocals. It gives you huge, larger than
life sound with a lot of details - like in good condenser mics, but at the same time
you have that classic lovely ribbon sound flavour, so much beloved by musicians and
sound engineers. Tracks recorded with RS-2 also blend very well with other
elements in the mix. That's a distinctive feature of all best mics on the market.
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Operation Safety
Power the RS-2 system exclusively with the voltage rating specified on the PSU
unit. It is always factory prepared for use in a country of purchase. The actual
operating voltage is stated on the back panel of PSU. In case of doubt, or when it's
necessary to change PSU voltage contact your local dealer.
Disconnect the unit from the electric power grid if you are not going to use it
for a long period of time. Unplug the power cord from the mains to cut power
supply to the unit.
Do not use this devices anywhere near water (for example in a bath room, a
damp cellar, near swimming pools, or similar environments). Otherwise your are
dealing with an extremely high risk of electrical shocks! RS-2 should also not be
installed near equipment which produce strong magnetic fields or extreme heat.
Be careful to not insert any object into any of the PSU chassis openings. You can
otherwise easily come into contact with dangerous voltage or cause a damaging
short circuit. Never allow any fluids to be spilled or sprayed on the RS-2 PSU. Such
actions can lead to dangerous electrical shocks or fire!
Never cover up the ventilation slots on the top of the PSU unit. If, during
operation the sound is interrupted or indicators no longer illuminate, or if
abnormal odor or smoke is detected, or if liquids are spilled on the unit,
immediately disconnect the power cord plug and contact your dealer.
Service and Repairs
Unplug the RS-2 PSU from all power and signal connections and contact your
local dealer when you think repairs are needed – or when moisture or foreign
objects may accidentally have reached inside the PSU housing, or in cases when the
any of the RS-2 system devices may have fallen and shows any sign of having been
damaged. This also applies to any situation in which the units have not been
subjected to any of these unusual circumstances but still is not functioning
normally or their performance is substantially altered. In cases of damage to the
power supply and cord, first turn off the main circuit breaker before unplugging the
power cord. All repairs are done at HUM audio Devices factory or in some cases at
authorized dealer's site.
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Do not open any of the RS-2 devices ourselves -
there are no user serviceable parts inside !
Replacement parts
Be sure that any authorized service technician uses original replacement parts
or those with identical specifications as the originals. Incorrectly substituted parts
can lead to fire, electrical shock or other dangers, including further equipment
damage. HUM Audio Devices can only guarantee quality of performance if correct
replacement parts are used.
Always be sure to ask a service technician to conduct a thorough safety check
and ensure that the state of the repaired device is in all respects up to factory
standards.
Cleaning
Do not use any solvents, as these can damage the chassis, rubbers or wood
finish. Use a clean, dry cloth (if necessary, with an acid-free cleaning oil). Great
for cleaning RS-2 's anodised mic body and front panels is dry micro fibre cloth.
Disconnect the device from power source before cleaning.
Declaration of CE Conformity
The construction of these units is in compliance with the standards and
regulations of the European Community.
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Active and Passive mode
There are two ways of using RS-2 microphone system:
1) Passive mode
This mode is similar to other ribbon microphones, when you decide to use
your favourite mic preamps. In this case you don't need to connect PSU and Remote
Controller at all, and have mic level signals directly from RS-2 mic body to your
external preamps.
When you have set up RS-2 with PSU and Remote units for active mode, but
decide to use passive mode – there is no need to disconnect the whole system, just
power off the PSU and RS-2 mic becomes passive. Because all functions and power
supply are controlled and switched by top class relays, there are no thumps and
other sound artefacts during power cycle or changing system connections. It is
always safe and convenient to change between modes of operation at any moment.
In passive mode you can of course use rotary RS-2 mic head, to record M/S
signals, but you must remember to decode it later somewhere in the chain, or in
the DAW.
Although passive mode can give you good results, we strongly recommend to
use RS-2 in active mode, when you benefit from all useful, unique features and the
best sound. Try, and we believe you will not want to loose them.
2) Active Mode
In this mode you connect all RS-2 system units, and have access to all
features and functions localized on RS-2 Remote Controller. In this situation you
have also line level signals coming out straight from L-R connectors on bottom of
RS-2 mic body, so you can connect directly your converters, tape or signal
processing units. When connecting RS-2 L/R outputs to a mixing console in active
mode, always use console's line inputs, unless you are searching for a special
effects when intentionally overdriving mic inputs.
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Installation and connections (Active mode)
This mode uses all the precisely crafted circuits, top Lundahl mic and line
transformers, high-end discrete class A preamplifiers based on legendary Jensen
JE990 opamps, passive transformer-based M-S matrix and passive lo-cut and eq
circuits, which are all built into the RS-2 mic body.
Active mode gives you strong benefits because ribbon mics are very sensitive
to preamp you use and also to quality and length of audio cables. In other words –
up to now you were always doomed to loose part of your sound when using any
ribbon mic, even not knowing about that. Our design eliminates all these
shortcomings. Extremely short signal path, noiseless and ultra linear preamplifiers
with high gain, and all other high-end circuits are precisely tailored to give you the
best sound you wish to have from ribbon mic.
RS-2 system connection scheme in Active Mode:
RS-2 microphone set has XLR cable for connecting Remote Controller and
special high quality 14-pin cable for connecting PSU included in the RS-2 set. 6
meters of 14-pin cable length should be more than enough in all typical studio
situations. In case when you need this cable longer than standard - you can order a
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longer one. XLR cable for Remote Controller is also 6m long, and in case when you
need more - you can connect any XLR cables you have in studio. There are no
special requirements on this cable, just every working cable with properly soldered
pins are adequate. We guarantee correct remote operation up to 100m, and even
more. Remember to use clean, direct line between studio rooms – no mic splitters
or trafos, they change line impedance which will cause remote malfunction.
XLR wiring scheme:
FEMALE MALE NOT
1. View from front
(mates to other connector)
2. Pins 1 and 2 are reversed when looking
at the other end (with solder points)
Because all control signals from Remote Controller and it's DC power are
conducted via single XLR cable, you have big degree of freedom in connecting the
Remote Controller. You can easily use existing studio cables or multicores to do
connectons between studio rooms, or if you are setting the RS-2 mic in studio room
or record yourselves - you can also take the RS-2 conroller with you to tweak the
sound there.
Power Supply Unit
Sound quality of all audio equipment strongly depends on good power supply.
That's why we designed very high quality PSU for RS-2 system.
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PSU is based on custom shielded trafo with individual voltages for audio and
control parts of RS-2 system, and best Linear Technology voltage regulators. You
have also soft start and protection during power cycle, so no thumps and other
sound artefacts are present on your monitors. Although it is safe to turn on/off PSU
or reconect RS-2 system on working monitors, it is good to get into the habit of
muting the monitors output before making any substantial changes in any of your
audio connections.
We strongly recommend using good quality, custom shielded AC cable
included in RS-2 set to power the unit.
Always connect the RS-2 PSU to the AC outlet with
correct voltage stated on the back panel.The unit
is prepared to use in a country of purchase.
Be sure also to use correct fuse adequate to
operating voltage !
There is possible to change voltage – contact your local dealer in case you
need to do that.
Hand Lever operation
RS-2 microphone swivel has a special rotatable hand lever with built-in
spring mechanism. Together with locking clutch action it provides fast and
convenient change of microphone angle position.
Thanks to the spring mechanism you can tighten or loose the lever fully even
when only small rotation angle is possible. To make full use of this feature - just
pull the lever towards the grey arrow , rotate to a new required starting position
(black arrow ) and release. Then you can continue to tighten or loose the lever.
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Stereo L/R (Blumlein) and M/S modes
In active mode, RS-2 can record 2 channel audio in three modes: Stereo L/R
(Blumlein), M/S encoded and M/S decoded into L/R, with stereo image fully
controlled by tweaking Remote Controller gain pots. Rotatable mic head can easily
change RS-2 recording mode from Stereo L/R to M/S, without any need to change
stand and mounting position. Spring mechanism in rotatable head bearing will
gently lock the head in choosen position.
There are two possible configurations when designer considers stereo ribbon
motors arrangement: from point of wiev of microphone, or from point of wiev of
sound source. We choosed configuration from microphone point of view. You can
imagine it like looking on the piano: left (bottom) ribbon looking on left hand, and
right (upper) ribbon looking on the right hand. This arrangement is taken into
consideration because it seemed more natural to us. Both motors have typical
figure of eight pattern.
Besides stereo and M/S applications of course you can always use any of the
two RS-2 channels for recording mono sources, like vocals. When you decide to
record mono source, it is good idea to rotate head to M/S position and turn Remote
Controller SIDE gain pot to zero, than sing or play instrument to the upper ribbon.
Of course you can be creative here and instead of recording mono track, you can
make use of M/S mode and gradually increasing SIDE gain expand the stereo image.
Useful Remote Controller DIM switch reduces preamps gain to minimum to
avoid unwanted sounds in monitors during mic position change or rotating the head
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