CAAS Audio EPre User manual

CAAS Audio
Elysian Pre-amplifier (EPre)
User Manual

Table of Contents
Elysian Pre-amplifier (EPre) Overview..................................................................................................................................3
CAAS Audio EPre Features.....................................................................................................................................................................4
CAAS Audio EPre Specification...............................................................................................................................................................5
Important Precautions (Mandatory).......................................................................................................................................6
EPre ront Panel Explained..................................................................................................................................................7
EPre Rear Panel Explained..................................................................................................................................................7
Getting Started......................................................................................................................................................................8
Installation................................................................................................................................................................................................8
The Mains Supply.....................................................................................................................................................................................8
The Input Output Options.........................................................................................................................................................................8
Operation..................................................................................................................................................................................................8
arm Up Period.......................................................................................................................................................................................9
Partnering Equipment & Components......................................................................................................................................................9
CAAS Link................................................................................................................................................................................................9
Ground Lift & Ground Loops....................................................................................................................................................................9
Maintenance..........................................................................................................................................................................9
Warranty (3 Year Guarantee)..............................................................................................................................................10
Page 2

Elysian Pre-amplifier (EPre) Overview
The Elysian Pre-amplifier (EPre) is a reference standard balanced pre-amplifier designed to produce the
highest audio playback quality possible.
The EPre is machined from a single piece of extremely high grade aluminium, incorporating a dual monaural
pre-amplifier with dedicated transformers and power supplies for the left channel, right channel and digital
sections.
The EPre is a true reference design which has met our aim to produce an outstanding sounding,
unsurpassed pre-amplifier with a remote controllable relay switched volume control and both single ended
and balanced inputs and outputs.
The EPre houses six (three per channel) separate zero feedback, class A operating (with zero switching
distortion), DC coupled amplifier modules. This unique topology allows selection of the correct amplifier
module and allows the EPre to configure the most direct and purest signal path possible for any input /
output configuration.
The purest most direct connection will be achieved when operating in either single ended (RCA) to single
ended (RCA) or balanced (XLR) to balanced (XLR) mode. When the EPre is configured to operate in either
of these modes, the signal path will consist of just the relay switched volume control and a single (or parallel
for balanced) zero feedback J ET buffer amplifier.
Volume control is achieved through a state of the art 128 step, silver contact relay switched, fixed precision
resistor volume control. This is a state of the art complex system of switching relays, however sonically it out
performs all standard potentiometer based volume controls.
The EPre has an extremely low noise floor with greater spacial refinement, dynamic accuracy and fine detail
retrieval than any other pre-amplifier on the market.
All the analogue signal sections of the EPre are DC coupled from the input to the output and have a very
short signal path. Ultra low frequency DC servo circuitry (NIDS) is used to maintain extremely low DC
operating levels.
The EPre is fitted with twelve dedicated discrete regulated power supplies for both Left and Right analogue
channels and seven separate regulated supplies for the digital sections.
The power supply is a key component in achieving the maximum performance from the audio sections and
for this reason the EPre is fitted with a high specification mains filter and three separate transformers, one for
the analogue sections and two for the digital sections.
The CAAS EPre has been designed to produce the highest audio quality possible. This has been achieved
through the following CAAS Audio proprietary technologies.
Page 3

CAAS Audio EPre Features
•Single chassis dual mono construction
•Single block aluminium construction
•Three (3) pairs of balanced (XLR) inputs
•Two (2) pairs of single ended (RCA) inputs
•One (1) pair of balanced (XLR) outputs
•One (1) pair of single ended (RCA) outputs
•irmware controlled relays and circuitry.
•128 step silver contact, relay switched, fixed precision resistor volume control
•Remote control volume, input select and mute function.
•CAAS Link (12V trigger for CAAS power amps)
•DC Coupled from input to output
•Ultra linear, ZERO feedback, J ET Class A buffer stage for the purest signal transfer
•Switched amplifier modules for the most direct signal path possible
•Separate transformers for the left analogue, right analogue and digital sections
•19 regulated power supplies: 12 dedicated discrete regulated power supplies (analogue sections)
and 7 regulated supplies (digital sections)
•Solid aluminium hand held remote control
•Available in All Silver or All Black.
•350mm (W), 330mm (D), 80mm (H), 8.6kg.
Page 4

CAAS Audio EPre Specification
Gain:
SE-to-Balanced +6dB to -44dB & Mute (128 steps), RCA-to-XLR
SE-to-SE 0dB to -50dB & Mute (128 steps), RCA-to-RCA
Balanced-to-Balanced 0dB to -50dB & Mute (128 steps), XLR-to-XLR
requency Response <1Hz to >100kHz (-3dB) DC Coupled
20Hz to 20kHz (+/-0.1dB)
Analogue Input 4V RMS (Max) per phase
Analogue Output 4V RMS (Max) per phase
Input Impedance >27 kohms (RCA)
>27 kohms per phase (XLR)
Output Impedance 60 ohms per phase (XLR)
60 ohm (RCA)
THD < 0.01% @1kHz (0dB level, 2V RMS)
Crosstalk <-90dB
Output SNR (A-WTD) ~100dB
Output DC Offset <+/-1mV
Power Consumption < 20W (Idle), < 0.5W (Standby)
use Rating T500mA
Analogue Inputs 2 x L/R Pair RCA
3 x L/R Pair XLR
Analogue Outputs 1 x L/R Pair RCA (Variable)
1 x L/R Pair XLR (Variable)
Mains Transformers 3 x 15VA (toroidal)
Dimensions 350mm (W), 330mm (D), 80mm (H)
Weight 8.6kg
Remote Solid aluminium
All specifications are subject to change at any time.
Page 5

Important Precautions (Mandatory)
Water and moisture
The EPre should not be used near water. Care should be taken not to allow the EPre to fall into water or
other liquids and ensure that liquids are never spilled onto or into the EPre.
Power sources
The EPre voltage and current rating is indicated on the rear panel of the unit. This will state either 240Vac or
120Vac. Two T1A time-lag fuses are included for 120V versions and two T0.5A fuses are included for the
240V versions. The input frequency rating of the power supply is 50Hz to 60Hz. The EPre typically draws
less than 20W during the normal operation. Please verify that the indicated voltage requirement is consistent
with the mains voltage in your location.
rounding
We provide a standard IEC AC mains cable that fits into the rear of the EPre. The EPre is equipped with an
earth ground provided by this cable and connection. DO NOT defeat this ground, the EPre should always be
grounded. It is dangerous to operate the EPre without a ground connection. Additionally the EPre may not
function correctly without a ground connection.
Power and Signal cables
The EPre is supplied with a power cable that meets UK legislated requirements. As with all audiophile
equipment the power cable should be the last item attached and the first item removed whenever equipment
is added or removed from the audio chain. Any cables (power or signal) should never be connected or
removed while the equipment or supporting equipment is powered up. ailure to pay attention to this
precaution may result in damaged equipment.
Ventilation
Audio equipment may run hot. The installation must allow for this heat dissipation. We recommend free air
circulation around the product. This can best be achieved by leaving at least a 20cm gap around the unit.
The EPre should not be installed or situated near any other source of heat (e.g. central heating radiator or on
top of an amplifier).
Servicing
To reduce the risk of fire, electrical shock or other injuries, the user should not attempt to service the EPre.
Please do not open the EPre. There are no user serviceable parts inside the EPre. Opening the EPre will
invalidate any warranty offered. Servicing must be referred to qualified service personnel only.
Burn in period
As is usual with high end audio equipment, when you first power up the EPre, you may not experience the
maximum performance of this pre-amplifier, the EPre can require a burn in period of up to 100 hours.
Additionally the performance of the EPre can vary slightly over its warm up period.
Page 6

EPre Front Panel Explained
(1) (2) (3) (4) (5) (6)(7)(8)(9)(10)
1. IR sensor (for remote control).
2. Standby LED (red for standby).
3. Standby / On select button.
4. Volume control knob.
5. Input select button (toggles through inputs).
6. 1 LED (Balanced input 1 selected, XLR).
7. 2 LED (Balanced input 2 selected, XLR).
8. 3 LED (Balanced input 3 selected, XLR).
9. 4 LED (Single ended input 4 selected, RCA).
10. 5 LED (Single ended input 5 selected, RCA).
The selector switch on the front panel cycles through the inputs. By pressing and releasing this button, you
can toggle through the inputs, 1, 2, 3, 4, 5 and then back to 1 etc... Input 1 is the default turn on selection.
These inputs can also be selected using the remote control.
EPre Rear Panel Explained
(2) (6) (8) (10) (12)
(1) (3) (4) (5) (7) (9) (11) (13) (14)
1. Mains power input and use.
2. Power switch.
3. CAAS Link (12V trigger for the control of CAAS power amplifiers).
4. Single ended RCA inputs 4 & 5 (Right channel).
5. Balanced XLR input 3 (Right channel).
6. Balanced XLR input 2 (Right channel).
7. Balanced XLR input 1 (Right channel).
8. Balanced XLR output (Right channel).
9. Single ended outputs (Left & Right channels).
10. Balanced XLR output (Left channel).
11. Balanced XLR input 1 (Left channel).
12. Balanced XLR input 2 (Left channel).
13. Balanced XLR input 3 (Left channel).
14. Single ended RCA inputs 4 & 5 (Left channel).
Page 7

etting Started
Thank you for purchasing a CAAS Audio Elysian Pre-amplifier (EPre). The Elysian range have been
designed to meet the highest standards of performance, sound and build quality.
The EPre should arrive in a well packaged box weighing slightly under 10kg. This should mean that your
EPre arrives in pristine order. If this is not the case please contact your retailer immediately.
While unpacking, please take care to always lift with bent knees and a straight back, using your leg
muscles to lift, in accordance with government HSE guidelines.
Installation
The EPre is a single chassis dual mono pre-amplifier.
The EPre analogue audio circuitry operates in class A mode and therefore the EPre will operate warm to the
touch. or this reason adequate ventilation is mandatory. Place the EPre in its preferred listening position,
taking care to insure that it has adequate ventilation (CAAS recommend > 20cm all around & >30cm above),
is not close to any heat radiating sources and is installed on an equipment stand capable of supporting in
excess of 10kg weight.
Ensure when connecting the power cable that any extension leads necessary are rated at 13A or above. (Do
not use extension cables unless absolutely necessary).
The Mains Supply
The EPre is available in two standard mains input versions; the 240V UK and European and the 120V USA.
Please check the rear of your unit to make sure the right input voltage is marked.
The Input Output Options.
The EPre has two pairs of single ended (RCA) inputs and three pairs of balanced (XLR) inputs on the rear of
the unit. All inputs are DC coupled from input to output (this is done for maximum sound quality) so please
ensure that the source components do not exhibit a large output DC offset.
When connecting the interconnect cables, observe the flow polarity of your cables. Only ever connect and
disconnect the cables while the amplifier is powered off or in standby mode (front panel red LED illuminated).
Take care not to short circuit the connectors or cables at any time as this may damage the EPre. Once you
are certain that all cables are correctly fitted at both ends, you are ready to power up the EPre.
Operation
Power the EPre up by turning the switch on the rear of the unit to the ON (I) position. This is a mechanical
switch and will disconnect the product from the main supply. Once turned on the front red standby LED will
illuminate (the EPre is in standby mode). Press and release the front panel standby button once (the button
next to the red standby LED), this will switch the EPre ON and the first blue LED (input 1), on the other side
of the volume control will illuminate. All the EPre audio circuity is powered down while in standby mode and
only powered up when the EPre is fully switched on. Once switched on, the EPre may take as long as 20
minutes to reach optimum performance.
Once fully ON the EPre remote will operate and all functions can be accessed (volume up, volume down,
input select and mute). To select a different input, press and release the input select button either on the
remote or on the front of the unit (next to the blue LEDs at the right of the volume control). Each press will
toggle to the next input so keep pressing and releasing until you have the right input. The input numbers on
the front panel (above each LED) directly relates to the rear panel inputs.
Page 8

Warm Up Period
Although the EPre will produce exceptional performance from the first time it is switched on, this
performance will improve as components settle in. The greatest improvement to performance will occur in
the first 50 hours of operation. After 100 hours or so the pre-amplifier performance will remain consistently
high.
Each time the pre-amplifier is switched on, the EPre will require at least 20 minutes to reach its optimum
operating conditions.
Partnerin Equipment & Components
The Elysian Pre-amplifier is a perfect match for CAAS Audio's DAS and E100 mono-block power amplifiers.
The Elysian Pre-amplifier has a buffered output stage with a low output impedance and hence a good to high
damping factor, therefore interconnect cable choice and power amplifier choice may be less critical than with
some pre-amplifiers (specifically passive ones). Nevertheless, to maximise the audio performance, CAAS
Audio recommend keeping interconnect cable lengths to an absolute minimum and ensuring that both left
and right cables are identical in both length and type.
CAAS Link
CAAS Link is a proprietary control system design to allow connection and control between CAAS Audio
products. The EPre CAAS link incorporates a 12V trigger. When The EPre is in standby mode 12V DC is
applied to the CAAS Link port. When the CAAS Link cables are connected between the EPre and any CAAS
Audio power amplifiers, this connection will automatically power down the CAAS Audio power amplifier(s).
When the standby / on button is pressed and the EPre is switched ON, the power amplifier(s) will
automatically switch on as well.
Note: The main power switch must be ON for the CAAS link to operate.
Important: CAAS Link is only to be used with CAAS Audio products.
Ground Lift & Ground Loops
The Elysian Pre-amplifier is not fitted with a ground lift switch. CAAS Audio believe the practice of
disconnecting grounds to be detrimental to the overall system quality and in some instances dangerous. The
Elysian Pre-amplifier has been designed to minimise internal ground loops and reduce the effect of
connecting equipment ground loops. The Elysian Pre-amplifier should operate with no audible mains hum. If
mains hum (and / or ground noise) is present then the resulting noise is due to the preceding source
components, the power amplifier or mains pick up on unconnected inputs and not the Elysian Pre-amplifier.
Maintenance
The following routine maintenance should be performed on a periodic basis:
Clean the exterior surfaces of the unit with a soft, dry, lint-free cloth. Do not use alcohol, benzene, acetone-
based cleaners, or strong commercial cleaners. Do not use a cloth made with steel wool or metal polish. If
the unit is exposed to a dusty environment, a low-pressure blower may be used to remove dust from its
exterior.
Page 9

Warranty (3 Year uarantee)
To reduce the risk of fire, electrical shock or other injuries, the user should not attempt to service the EPre.
Please do not open the EPre. There are no user serviceable parts inside the EPre. Opening the EPre will
invalidate any warranty offered. Servicing must be referred to qualified service personnel only.
This warranty is offered in relation to purchases made in the United Kingdom, Eire and European Economic
Area (EEA) only and shall be governed by the laws [applying in the country in which purchase of the product
takes place]. Consumer statutory rights applying under the laws [pertaining in the country of purchase] shall
not be adversely affected by any terms and conditions contained herein. All CAAS Audio products are
covered by a standard 3-year manufacturers’ warranty. This covers parts and labour, subject to terms &
conditions. This warranty is not transferable outside the European Economic Area.
If a CAAS Audio product is defective in normal domestic use, due to a fault in materials or workmanship,
CAAS Audio will at its discretion (and subject to the terms contained herein) either repair or
replace it free of charge within a reasonable time after return of such product to CAAS Audio during the
warranty period. This warranty is offered to the first purchaser only and covers the cost of parts and
associated labour required to correct such defects in materials or workmanship arising and advised to your
retailer or CAAS Audio during a period of three (3) years from the original date of purchase.
This Warranty does NOT cover:
1. Damage to CAAS Audio products while in the possession of a shipper, retailer, or consumer and not
caused by defects in materials or workmanship.
2. Damage or defects caused by abnormal or unreasonable use (including repairs or alterations of
products by a person or company other than CAAS Audio).
3. Damage to CAAS Audio products arising due to or from normal wear and tear.
4. Damage resulting from misuse, neglect, abuse, accidents, acts of nature, improper installation,
improper removal or cleaning.
5. Damage resulting from failure to follow the instructions in the user manual or repair or attempted
repair by unauthorised personnel or company.
6. Initial set-up, check-ups or charges incurred for installation of the product.
7. Any cause other than a product defect due to a fault in materials or workmanship.
8. Any product where the serial number has been defaced, modified or removed.
9. Any CAAS Audio product purchased outside the European Economic Area.
Note: The term “Damage” includes, malfunction, deterioration and failure to meet specifications.
CAAS Audio will pay for all parts and labour covered by this warranty. The purchaser must pay all shipping
charges if it is necessary to return the product to CAAS Audio or your retailer. However, if the required
repairs are covered by this warranty CAAS Audio will pay for the return shipping to any destination within the
UK & Eire. Whenever warranty service is required you must present the original dated sales receipt or other
proof of purchase.
The equipment should be packed in its original packing. Do not return your product to CAAS Audio without
consulting with and approval from CAAS Audio. If you are returning any product, you should use a reputable
carrier - do NOT post. CAAS Audio cannot accept responsibility for the unit while in transit to the retailer or
CAAS Audio.
Please ensure that your equipment is insured by you during any transit or shipment for repair.
This warranty applies from the date of purchase for the duration of three (3) years. Under no circumstances
will this change. If a product is returned for repair or servicing or other, the remainder of the warranty from
the original date of purchase is the warranty given on the repair, service or other and NOT a further three (3)
year warranty.
Page 10