Bryston 2.5B3 Owner's Manual

2.5B3 Amplier

Owner’s Manual

Important Safety Instructions

The lightning flash with arrowhead symbol within an equilateral triangle, is

intended to alert the user to the presence of un-insulated “dangerous volt­age “ within the product’s enclosure that may be of sufficient magnitude to constitute
a risk of electric shock to persons.

The exclamation point within an equilateral triangle is intended to alert the user
to the presence of important operating and maintenance (servicing) instructions

in the literature accompanying the product.

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Do not use this apparatus near water.

6. Clean only with dry cloth.

7. Do not block any ventilation openings. Install in accordance with the

manufacturer’s instructions.

8. Do not install near any heat sources such as radiators, heat registers, stoves, or

other apparatus (including amplifiers) that produce heat.

9. Do not defeat the safety purpose of the polarized or grounding-type plug. A

polarized plug has two blades with one wider than the other. A grounding type
plug has two blades and a third grounding prong. The wide blade or the third
prong are provided for your safety. If the provided plug does not fit into your
outlet, consult an electrician for replacement of the obsolete outlet.

10. Protect the power cord from being walked on or pinched particularly at plugs,

convenience receptacles, and the point where they exit from the apparatus.

11. Only use attachments/accessories specified by the manufacturer.

12. Use only with the cart, stand, tripod, bracket, or table specified by the
manufacturer, or sold with the apparatus. When a cart is used use
caution when moving the cart/apparatus combination to avoid injury
from tip-over.

13 Any terminals marked with the preceding symbol are HAZARDOUS
LIVE and any wiring connected to these terminals must be installed
by an INSTRUCTED PERSON or with ready-made leads or cords.

14. Unplug this apparatus during lightning storms or when unused for long periods of

time.

15. Refer all servicing to qualified service personnel. Servicing is required when the

apparatus has been damaged in any way, such as power-supply cord or plug is
damaged, liquid has been spilled or objects have fallen into the apparatus, the
apparatus has been exposed to rain or moisture, does not operate normally, or has

been dropped.
WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS
APPARATUS TO RAIN OR MOISTURE. DO NOT EXPOSE THIS EQUIPMENT TO DRIPPING OR
SPLASHING AND ENSURE THAT NO OBJECTS FILLED WITH LIQUIDS, SUCH AS VASES, ARE
PLACED ON THE EQUIPMENT. TO COMPLETELY DISCONNECT THIS EQUIPMENT FROM THE AC
MAINS, DISCONNECT THE POWER SUPPLY CORD PLUG FROM THE AC RECEPTACLE.
THE MAINS PLUG OF THE POWER SUPPLY CORD SHALL REMAIN READILY OPERABLE.

BRYSTON LIMITED WARRANTY

Bryston analog audio products are warranted to be free from manufacturing defects for twenty (20) years from the original date of manufacture. The warranty includes parts and labour.
Bryston digital products and cables are warranted for five years from the original date of manufacture. The warranty includes parts and labour.
Bryston products having motorized moving parts, excluding motorized volume controls, are warranted for three years from the original date of manufacture. The warranty includes parts
and labour.
Bryston will remedy the problem by repair or replacement, as we deem necessary, to restore the product to full performance. Bryston will pay return shipping only for the full length of
the specific product's warranty.
In the event of a defect or malfunction, contact Bryston’s repair centers for return authorization. Products must be returned using original packaging material only. Packing material may
be purchased from Bryston if necessary. This warranty is considered void if the defect, malfunction or failure of the product or any component part was caused by damage (not resulting
from a defect or malfunction) or abuse while in the possession of the customer. Tampering by persons other than factory authorized service personnel or failure to fully comply with Bryston
operating instructions voids the warranty. This warranty gives you specific legal rights and you may also have other rights which may vary from province to province and country to country.
As of 2006-02-22 Bryston will only warranty Bryston products purchased through authorized Bryston dealers. Bryston products with a date code of 0608 or higher (date code format is
“yyww”, where “yy” is the two least significant digits of the year and “ww” is the week of the year) must be accompanied by a copy of the bill-of-sale from a Bryston authorized dealer to
qualify for warranty service. The warranty is transferable from the original owner to a subsequent owner as long as a copy of the bill-of-sale from the original authorized Bryston dealer
accompanies the re-sale. The copy of the bill of sale to any subsequent owner need ONLY include the Name of the Bryston Authorized Dealer and the Model and Serial number of the
Bryston product The warranty will only be honored in the country of the original purchase unless otherwise pre-authorized by Bryston.

BRYSTON SERVICE in CANADA: BRYSTON SERVICE in the USA:

Postal address: P.O. BOX 2170, Stn. Main
PETERBOROUGH, ONTARIO
CANADA K9J 7Y4

Courier address: 677 NEAL DRIVE
PETERBOROUGH, ONTARIO
CANADA K9J 6X7

PHONE: [phone]
FAX: [phone]
E-mail: [e-mail]

79 COVENTRY ST., Suite 5
NEWPORT, VERMONT
U.S.A. 05855-2100

PHONE: [phone]
FAX: [phone]
E-mail: [e-mail]

BRYSTON SERVICE outside Canada and the USA:

contact your local distributor or

CHECK OUR WEB SITE: www.bryston.com
E-MAIL BRYSTON DIRECTLY: [e-mail]
FAX BRYSTON DIRECTLY: 01-705-742-0882
PHONE BRYSTON DIRECTLY: 01-705-742-5325

Table of Contents

Important Safety Instructions ....................................2

General.........................................................................3

Welcome ................................................................ 3

Description ............................................................3

Features .................................................................3

Shipping Box and Packing Material ...................... 3

Installation and Usage ................................................4

Ventilation .............................................................4

Connecting to A/C Power ...................................... 4

Connecting to Loudspeakers:

2 Channel Mode .....................................................4

Balanced vs. Single Ended Input .......................... 5

Power Conditioners ..............................................5

External Control Voltage ....................................... 5

Connecting to Loudspeakers: Bridged Mode .......6

Front Panel ..................................................................7

Rear Panel .................................................................... 8

2.5B3 Specications ................................................... 10

Dimensions ................................................................ 11

General

Welcome

Thank you for your purchase of a Bryston 2.5B3
(Cubed) amplier! Decades of ongoing research
and development have produced our highest
performing ampliers yet. Our customers are
a tremendous resource to whom we look for a
measure of success. Please feel welcome to contact
us with feedback and suggestions.

Description

The 2.5B3 is a dual-mono design audio power
amplier with two channels capable of 135 watts
each intended for use in very high performance
professional audio systems. Robust yet beautiful
machined aluminum enclosures house our
proprietary industry-leading circuit designs
resulting in exemplary performance observed both
in the listening space and in the laboratory.

C-Series variants are available in your choice of 17
inch or 19 inch wide non-rack mountable aluminum
dress panels anodized in clear (silver toned) or
black. PRO ampliers feature 19 inch wide rack
mountable dress panels in a black anodized front

nish and also include individual channel trims
located on the rear panel.

Features

Bryston 2.5B3 includes the following features:

• Switchable gain: 23dB or 29dB

• Balanced (XLR or TRS) input. Pin 2 positive.

• Single ended (RCA) input.

• SoStart circuitry for managing inrush current

upon initial power up.

• Wired remote control AC/DC trigger input and
pass through with supplied connector.

Shipping Box and Packing Material

Please keep the original shipping box and all
packing material. This will ensure the amplier is
protected in future transport. In the unlikely event
you have a problem and must return it for service,
you must use the proper packing material. Ship
the amplier only in the original packing material,
as the unit is not insurable by carriers otherwise.
Replacement packing materials consisting of a
shipping carton with plastic foam inserts is available
from Bryston for a small fee.

Installation and Usage

ready to be powered on.

Ventilation

Bryston has deliberately chosen to omit fans from
our ampliers in an eort to minimize the noise
level in your listening environment. Instead, we use
only passive heat sinks which are fully capable of
maintaining a safe operating temperature of the
amplier even under loud playback conditions. For
them to work most eectively, air must be
permitted to pass freely through the heat sink ns
and around the amplier. Maintain a minimum of

3.5 inches of space to each side, top and back of the
amplier when in use. Do not stack the ampliers
immediately on top of one another in an enclosed
cabinet. If you must stack the amps, you may need
to utilize fans or another active cooling mechanism
to ensure uninterrupted operation. If you repeatedly
experience channels shutting down due to heat,
rearrange the ampliers to have more surrounding
free space, or employ an active cooling solution.

Heat sinks may be up to 100° Celsius! Take
caution to prevent burns! Never operate the

amplier in a vertical position.

Connecting to A/C Power

Please check the Data Plate on the right rear of the
amplier to verify power requirements agree with
your location. See “10. Data Plate:” on page 9.
Plug the IEC-320 C14 end of the power cord into the
amplier, then plug the other end into an approved
and grounded A/C receptacle. The amplier is now

Connecting to Loudspeakers:
2 Channel Mode

Connection to loudspeakers is accomplished by
attaching high quality speaker cable to the Output
Binding Posts (see “Rear Panel” on page 8) per
the following instructions.

The RED binding post is connected to the positive
channel output. Connect this post to the (+)
terminal on the loudspeaker.

The BLACK binding post is connected to ground.
Connect this post to the (-) terminal on the
loudspeaker.

The output binding posts provide three dierent
interconnect options. Combinations may be used
when bi-wiring. Cables should be kept as short
as practical and should never be terminated with
connectors that may become confused for AC
power connectors. Cables should be dressed away
from input and power cables.

To prevent the risk of equipment damage or
personal harm, use only Class 2 rated loudspeaker
wire properly terminated and connected securely to
the binding posts.

Banana plugs oer a quick disconnect option.
Before inserting a banana plug into the binding
post, be sure to tighten the post nut to avoid rattling
and to provide full insertion of the banana plug.

From Preamplier

2

1

3

4

To Loudspeakers

2

1

3