AVID HIFI Reference User manual

Reference
High Performance Power Amplier
USER MANUAL

2
Topic Page
Welcome 3
Cauon 3
Key Reference Power Amplier features 4
Setup Procedure 5
Placement 6
Connecng the mains supply 6
Cable Selecon 6
Balanced and Unbalanced inputs 7
XLR connecon Standard 8
Output Connecons 9
Troubleshoong 10
Specicaons 11
Declaraon of Conformity 11
Warranty 12
Table of Contents

3
Welcome to your AVID Reference Power Amplier
Congratulaons on purchasing your AVID Reference Power Amplier. Using the highest quality materials and
built to the highest industry standards, your AVID Reference amplier should provide you with many years of
trouble-free enjoyment.
The Reference Power Amplier is available as either a mono unit (two required) or as a Stereo unit.
The basic instrucons are common to both units. Any dierences will be highlighted in the text.
Please read this manual carefully to ensure you understand all the features and operang funcons available.
Cauon
• These units are heavy, and it is recommended that at least two people are used when moving the unit.
• Care should be taken to ensure that the unit is switched o and unplugged from the mains before
connecng or disconnecng any other equipment to your Reference Power Amplier This is to protect
your speakers from any momentary high-level signals which, due to the high power capabilies of the
amplier, could cause damage.
• Please allow adequate venlaon (see ‘Setup procedure’)
• There are no user-serviceable parts inside—please do not, under any circumstances, remove the amplier
cover, doing so would expose you to potenally lethal voltages and will void your warranty.
• Only clean your Reference Power Amplier with a dry micro-bre cloth.
• Take care to ensure the unit is not exposed to water or other liquids. If you believe water may have
entered the case, turn the unit o at the socket immediately and seek advice from your dealer before
aempng to use it again.

4
Key Reference Features:
High Power, High Current capabilies
Your Reference amplier has an over-sized transformer and power reservoir far in excess of what the amplier
will demand in normal use. This design, along with fast-acng localised smoothing capacitors ensure that no
maer what the dynamic demands, your Reference amplier will always have more in reserve.
Balanced and Unbalanced input
Giving great exibility, the Reference Power Amplier provides the opon of using either balanced (XLR) or
unbalanced (RCA) connecons. Balanced input guarantees the best noise performance allowing the use of long
cable runs while unbalanced inputs ensure compability and convenience with all modern line level sources.
Ecient, silent cooling
All AVID Reference Ampliers use silent, passive cooling using generous aluminium heatsinks. Each heatsink
accommodates mulple, paralleled output devices capable of delivering much higher current than typically
required by the most dicult loudspeaker loads, whilst maintaining the highest levels of reliability.
Sophiscated Protecon
Due to the high power and current capabilies of your Reference Amplier, it is necessary to ensure that any
risk of damage due to incorrect set-up or a fault in the system is minimised. All Reference Ampliers
incorporate a sophiscated system that monitors key parameters at all mes. The front panel houses a display
made up of four LED indicators. Aer an inial check phase, this display should show a single blue LED,
indicang normal operaon. Any other illuminated or ashing LEDs indicate a fault. In this event, please refer
to the troubleshoong secon.
The system monitors for short-circuits, clipping (indicator light), gross clipping (output muted), DC-osets,
internal fuse failure and overheang.
Unparalleled build standards
Constructed using the highest quality materials suited to their applicaon. A substanal 3mm-thick steel
chassis which is clad in thick anodised aluminium plates providing mechanical damping and is nished to
compliment our range of Reference products
High quality connectors
Gold plated connectors are used throughout to design of the Reference Ampliers to guarantee long-term
reliable connecons. High current binding posts accept both convenonal 4mm plugs or spade connectors are
used for loudspeaker connecons.

5
Setup Procedure:
 Place the amplier in its nal posion.
 This amplier uses silent, passive cooling and therefore you must ensure adequate venlaon is
provided. Allow at least 50mm all around the cabinet, and do not place the unit in a closed cabinet.
 Connect the output from the Pre Amplier to the Power Ampliers input using either balanced or
unbalanced cables.
 Set the balanced/unbalanced switch to appropriate posion
 Connect speakers to output of amplier.
Switch-on procedure
 Ensure Pre-Amplier volume control is set to minimum.
 Always switch-on input devices (turntable, CD etc) and the Pre-Amplier BEFORE switching on the Power
Amplier.
 Having checked that all connecons to, and from the amplier are correct, switch on the Power
Amplier, using the switch on its rear panel.
 The unit employs an an-surge device during the rst few seconds of start-up. This employs a high power
resistor which is designed to dissipate a lot of power as heat—over me, this device may become dusty,
and this dust may result in a short-term ‘burning’ smell. This is NORMAL and no cause for alarm. The
smell will dissipate aer a few moments.
 Aer a few seconds, the LED indicators should nish their test sequence, and a single BLUE LED should be
illuminated (if not, please check TROUBLESHOOTING page).
 Start your source and slowly increase the volume seng unl you reach the required sound level.
Switching O
 Your Reference Power Amplier may be le powered up safely for long periods, however it is
recommended that it is switched o if you are going to leave it unused.
 Always switch o the Power Amplier BEFORE switching o any other connected devices.

6
CONNECTING TO THE MAINS SUPPLY
WARNING:
• Only connect to the mains once all other connecons are in place.
• The Reference Power Amplier uses a dedicated high current mains lead—do not aempt to use another
type. Once plugged in, the mains lead locks in place—you must acvate the red toggle if you wish to
disconnect the cable.
• Inspect all cables for any damage—please contact your dealer if you have any concerns.
CABLE SELECTION
Generally it is best to keep loudspeaker cable lengths as short as possible—having the power ampliers close to
your loudspeakers is a good idea, even if this means having longer line-level connecons (XLR, rather than RCA).
There is an enormous choice when it comes to selecng interconnecng and loudspeaker cables and, as with
most things, geng a consensus of what is best is impossible, we would however make the following
recommendaons when choosing cables:
General
1. Keep cable lengths as short as praccal and the same for both right and le channels
2. Choose high quality connectors to ensure long-term reliability (disconnect and reconnect occasionally to
clean connecons)
Loudspeaker Cables
1. Minimise cable resistance—choose a cable with a large cross-secon of copper core. This is especially
important when using low impedance loudspeakers, or parcularly long cable runs.
2. Cables come in all kinds of construcon, and may aect the perceived sound balance—this is highly
subjecve point and is best le to the listener to decide as to which suits the system and your tastes
PLACEMENT
• Although the amplier generally runs cool, you should always ensure that adequate venlaon is
maintained. Avoid placing your Reference Power Amplier where it may be aected by external heat
sources, or damp condions.
• The Reference Power Amplier is very heavy, and must be placed level, on its dedicated shelf, or directly on
the oor.
• The amplier is ed with heavy-duty roller feet to make posioning the unit as easy as possible.
• Do not place any objects on top of the amplier, which could obstruct air-ow.

7
There are two methods of connecng analogue audio devices, using either “Balanced” or “Unbalanced”
connecons. By far the most common is unbalanced – the main reason for this is cost - fully balanced system uses
almost twice as many components as a typical unbalanced system.
Unbalanced inputs
A normal, unbalanced system uses interconnects with just two conductors (normally using RCA connectors)—an
inner core that carries the audio signal, and an outer sheath that acts as a “Ground” or 0V reference. In an ideal
situaon, this would be all that is needed. Unfortunately, as well as transferring the intended signal, a cable is also
very eecve at picking up radio frequency noise. This noise can be generated by many things, for example the
operaon of light switches, thermostats , or uorescent lamps will commonly produce RF ‘spikes’. The result is a
combinaon of the two signals, as illustrated below:
Unfortunately, once the signal has become corrupted with noise, there is no method of removing this noise
without further damaging the original signal.
Balanced inputs
A balanced input uses a clever technique where instead of having just one signal conductor, there are two (as well
as a Ground). The standard connecon for a balanced input is the 3-pin XLR connector.
This method sends the original signal along one of the conductors, and a second idencal, but inverted one, down
the second conductor. Now, if this signal is corrupted by the same noise signal, both signals will be aected
idencally. Note the orange plot, which shows the inverted signal, the signal remains inverted, but the noise is not;
this is because, being in close proximity to each other, the two conductors pick up the noise signal at exactly the
same me (and therefore phase).
Now when the two wave forms are recombined (by subtracng one from the other, the noise cancels
itself out, leaving the original, noise-free signal.
Balanced and unbalanced inputs
Original signal Signal + noise
Balanced Signal Balanced signal + noise Recombined signal

8
XLR connecon Standard
As menoned previously, balanced inputs use two signal
conductors and a single ground conductor. For correct
operaon, it is vital that the correct connecon standards are
used. AVID adhere to the EIA Standard RS-297-A to ensure
compability with all modern audio equipment.
By convenon, the two signals are referred to as the posive phase (somemes referred to as ‘hot’) and the
negave phase (‘cold’).
The standard pin connecons are as follows:
PIN Connecon
1Ground
2Posive (Hot)
3Negave (Cold)
Mixed systems
Whilst it is possible to connect unbalanced units to Balanced units, this is not the opmum method, and
ideally a balanced source should be always be connected to a balanced input —the fact that the Reference
Power Amplier ulises both connecon types, allows the use of both connecon types with minimal
compromise in performance.

9
OUTPUT CONNECTIONS
Both the Mono and Stereo Reference Power Ampliers have two pairs of output connectors per channel.
This makes the use of Bi-Wired connecons straight-forward. If you are only using a single-wired
conguraon, then you only have to use one pair of connectors—please see the diagrams below for
guidance.
BIWIRED CONNECTION
SINGLE-WIRED CONNECTION
Mono amplier—in single-wire mode, you may
use either of the pairs of connector. Connect ‘+’
connector to the ‘+’ connecon of the speaker,
and the ‘-’ connector to the ‘-’ connecon on
the speaker.
Stereo amplier—in single-wire mode, you may
use either of the pairs of connector. Connect ‘+’
connector to the ‘+’ connecon of the speaker,
and the ‘-’ connector to the ‘-’ connecon on
the speaker. Connect ‘L’ pair to the le
speaker and ‘R’ pair to the right speaker.
Mono amplier—in bi-wire mode, connect one
pair to the HF terminals of your speaker and
the other pair to the LF terminals. Connect ‘+’
connector to the ‘+’ connecon of the speaker,
and the ‘-’ connector to the ‘-’ connecon on
the speaker.
Mono amplier—in bi-wire mode, connect one
pair to the HF terminals of your speaker and
the other pair to the LF terminals. Connect ‘+’
connector to the ‘+’ connecon of the speaker,
and the ‘-’ connector to the ‘-’ connecon on
the speaker. Connect ‘L’ pair to the le speaker
and ‘R’ pair to the right speaker.

10
TROUBLESHOOTING
Operation of your Reference Power Amplifier is generally straight-forward. When
you first switch on the amplifier, it will carry out a short self-diagnostic test. During
this process, the out put will remain muted. The Indicator LEDs will cycle through a
pre-programmed sequence. After a few seconds, and assuming no fault was found,
you should be left with a single BLUE LED indicator—this is the normal operating
state of the amplifier.
Any flashing lights after the initial start-up phase indicates that a possible fault has
been detected. In this case you should immediately switch-off the amplifier and
consult the following table to check what steps need to be taken.
OUTPUT
ENABLED ERROR SPEAKER FAULT THERMAL FAULT CORRECTIVE ACTION
BLUE RED RED RED
ON OFF OFF OFF NORMAL OPERATION OK
ON RANDOM
FLASH OFF OFF OVER LOAD REDUCE VOLUME LEVEL
ON OFF RANDOM
FLASH OFF OUTPUT CLIPPING REDUCE VOLUME LEVEL
OFF 2 FLASHES OFF OFF EXTREME CLIPPING REDUCE VOLUME LEVEL
OFF 3 FLASHES OFF OFF INTERNAL FUSE FAILURE CONTACT DEALER
OFF 4 FLASHES OFF ON OVERHEATING
1. CHECK FOR ADEQUATE
VENTILATION
2. REDUCE VOLUME
3. CHECK THAT
LOUDSPEAKERS ARE
COMPATIBLE WITH THE
AMPLIFIER
OFF 5 FLASHES OFF OFF DC OFFSET
1. SWITCH OFF AMPLIFIER,
LEAVE FOR A FEW
SECONDS AND THE
SWITCH ON AGAIN. IF
PROBLEM PERSISTS….
2. CONTACT YOUR DEALER
OFF 6 FLASHES ON OFF SHORT CIRCUIT ACROSS
OUTPUT
CHECK LOUDSPEAKER
CONNECTIONS AT BOTH ENDS
BEWARE: THE AMPLIFIER CONTAINS POTENTIALLY LETHAL VOLATGES. THERE ARE NO USER-SERVICEABLE PARTS INSIDE
THE AMPLIFIER — ANY ATTEMPT BY AN UNAUTHORISED PERSON TO OPEN THE UNIT MAY VOID YOUR WARRANTY.

11
Specicaon
INPUTS
Line (RCA and XLR)
Nominal sensivity: TBC V
Input impedance: TBC kΩ
Maximum input: TBC Vrms
Frequency response: TBC Hz—TBC kHz ± 0.2dB
OUTPUT
Stereo Power Amplier (both channels driven)
Power: into 8 Ohms (<0.1% THD) TBC W
into 4 Ohms (<0.1% THD) TBC W
Mono Power Amplier
Power: into 8 Ohms (<0.1% THD) TBC W
into 4 Ohms (<0.1% THD) TBC W
Dimensions: 500 x 650 x 300mm (WxDxH)
Net weight (each): 68Kg (150lbs)
Packaging (each): 730 x 570 x 400mm (WxDxH)
Shipping weight (each): 81Kg (179lbs)
DECLARATION OF CONFORMITY
EC Declaraon of Conformity 06 December 2017
We declare that our Reference Mono & Stereo Amplier conforms to direcves
and harmonized internaonal standards:
EMC (89/36/EEC) Electromagnec conformity
BS EN 60065: 1994
Safety requirements for mains operated electronic and related apparatus for household and similar use.
CENELEC HD21/22 Flexible cables and cords
EN 55020: 1988 Electromagnec Immunity
EN 55013: 1990 Electromagnec Emissions
C. Mas Director AVID HIFI Limited

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Warranty Statement UK Residents
AVID HIFI Limited products are warranted against defects in materials and workmanship for a period of two years from the original date of
purchase, or no later than three years from the date of shipment to an authorized AVID agent, which ever comes rst, extending to ve
years subject to the product owner having submied the Registraon form (www.avidhi.com/register.htm). Also the following condions
being observed.
• The product must have been purchased through an authorized AVID dealer
• By default, the warranty is in favour of the original purchaser only, however warranes are transferable providing the new owner
completes the online product registraon form. In this case, warranty obligaon will pass from dealer to manufacturer.
• During the warranty period, AVID will repair, or replace any defects due to material or workmanship, without charge for parts or
labour.
• Should product need to be returned, a wrien descripon of the defect and a photocopy of the original purchase receipt must
accompany it. Receipts must show the model, serial number, date of purchase, name and address of purchaser and authorized
dealer and the price paid.
• Returned product must be packed in the original packing and returned to AVID or original dealer by the customer at his/her
expense. AVID will pay return freight of its choice.
• The warranty is void if the product has been used or handled other than in accordance with the instrucon manual supplied, abused
or misused, damage by accident or neglect or in being transported, or the defect is due to the product being repaired or tampered
with by anyone other than AVID or an dealer with prior authorizaon.
• The warranty is void if the product serial number has been removed, altered or made illegible.
• The warranty is void if the product has been taken out of the country of purchase.
• AVID shall not be held liable for incidental or consequenal damages of any kind arising from the sale or use of its products.
• The warranty applies to ex-demonstraon product, using manufacture date as purchase date.
• Where the product is sold under a consumer transacon (as dened by the Sale of Goods Act 1979) the statutory rights of the
purchaser are not aected by this warranty.
• Products are sold on the basis of specicaons applicable at the me of sale. AVID shall have no obligaon to modify or to update
products once sold.
Outside UK
AVID has formal distribuon in many countries throughout the world. In each country the AVID importer has contractually accepted the
responsibility for the product warranty. Warranty should normally be obtained from the imporng agent or distributor from whom you
obtained your product. In the unlikely event of service required beyond the capability of the importer, AVID will, of course, back up the
warranty.
• Where product has been either supplied directly or there is no current distributor, AVID accepts responsibility for the warranty
period. Returned product must be packed in the original packing and returned to AVID by the customer at his/her expense.
AVID will pay return freight of its choice. The warranty is only valid in the country of purchase.
• Products outside their original desnaon requires that units with remaining warranty be returned to the country of purchase for
the warranty to be valid. Customer is responsible for freight both ways and all associated import and export charges.
• Foreign distributors are not required to provide warranty service, repair or change AC mains voltage on units that they did not origi-
nally import and sell.
• Foreign distributors may at their discreon oer service for a fee.
MISCELLANEOUS. ANY IMPLIED WARRANTIES RELATING TO THE ABOVE PRODUCT SHALL BE LIMITED TO THE DURATION OF THIS
WARRANTY. THE WARRENTY DOES NOT EXTEND TO ANY INCIDENTAL OR CONSEQUENTIAL COSTS OR DAMAGES TO THE PURCHASER.
WARRANTOR. Inquiries regarding the Limited Warranty may be sent to the following address:
AVID HIFI Limited. Bicton Industrial Park, Kimbolton, Hunngdon. PE28 0LW ENGLAND

13

14
AVID HIFI Ltd
Bicton Industrial Park,
Kimbolton, Huntingdon,
Cambridgeshire.
PE28 0LW
ENGLAND
Tel: [phone] — Website: www.avidhifi.com - Email: [email protected]k
Company Registered No: 5435528 — VAT Registration No: GB 694 9858 48 — Directors: C. Mas & S.J. Mas
Updated 3rd January 2018