BRYSTON BAX1 Black BAX-1_MANUAL.pdf

BAX-1 Active DSP Crossover

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 uninsulated “dangerous voltage “ within
the product’s enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons.

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 manufactur-

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

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

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.

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.

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

er’s instructions.

time.

14. Refer all servicing to qualified service personnel. Servicing is required

other apparatus (including amplifiers) that produce heat.

when the apparatus has been damaged in any way, such as pow­er-supply cord or plug is damaged, liquid has been spilled or objects

ized 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

have fallen into the apparatus, the apparatus has been exposed to rain or moisture,
does not operate normally, or has been dropped.

15. Do not open. NO USER SERVICEABLE PARTS INSIDE

an electrician for replacement of the obsolete outlet.

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.........................................................................4

Welcome ................................................................4

Description ............................................................4

Features ................................................................. 4

Shipping Box and Packing Material ...................... 4

Installation ...................................................................4

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

Connecting to A/C Power ...................................... 5

Connecting to an Audio System ...........................5

Connection Diagram .............................................5

Choosing Amplication.........................................5

Connect to Network ..............................................5

First Run ................................................................. 5

Bass Adjustment ..........................................................6

A Word About Room Tuning ..................................6

Measuring In Room Response ..............................6

DSP Filter Setup ....................................................7

Front Panel ..................................................................8

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

Specications and Dimensions ..................................9

Network Connection .................................................10

Firmware Update.......................................................10

Remote Control .........................................................11

Serial Protocol ..................................................... 11

Command Format ............................................... 11

General

Welcome

Thank you for your purchase of a Bryston
Active Loudspeaker System! Our class leading
loudspeakers and ultra high performance DSP
crossover platform combine with your choice

of Bryston amplication to form a unique high

performance playback system through which you
can hear details you never thought possible. We
welcome your feedback and hope you enjoy your
new Bryston Active Loudspeakers for many years to
come.

Description

Fully active loudspeakers dispense with passive
crossovers that are built into conventional
loudspeakers in favor of crossovers inserted before

amplication is applied. The benets are many
including increased exibility with lter shapes,
the ability to make ne-grained adjustments
which result in improved on and o axis response
(these are oen competing objectives in passive
loudspeakers), direct coupling of the loudspeaker

to the driver which avoids losses inherent in passive
crossovers and more. Bryston Active Loudspeakers

combine decades of research into acoustics,
electronics, amplication as well as state of the

art components to recreate your recordings with

stunning realism. The BAX-1 Active DSP Crossover is

a core component of this system.

The BAX-1 is a state of the art DSP crossover that

has been specially programmed at the factory

for compatibility with your specic model of

Bryston Active Loudspeakers. It is comprised of
two channels of analog to digital conversion which
convert incoming full range analog audio from your

preamplier to an equivalent digital audio signal

sampled at 96kHz and decimated to 24 bits. This
signal passes to a high powered DSP core which

performs the 3-way crossover function for each
channel and any user selected lters desired for

altering the bass response of the loudspeakers
in the room. Three bands of audio per channel
are then passed to 6 digital to analog converters

followed by fully discrete balanced analog outputs

which in turn feed 3 amplier channels per
loudspeaker. The BAX-1 only accepts balanced input

and provides balanced output. No single ended

audio connections are available. If you require
single ended connections, XLR to RCA adapters can

be used.

The system can be user controlled through a simple

and intuitive web-application for setup. Network
connection is required for those who desire to

tailor the bass response of the loudspeaker to the

room and for rmware updates but is not otherwise

necessary.

Features

Bryston BAX-1 includes the following features:

• 6 DACs and 2 ADCs by AKM

• Audio sensing auto-power on

• Network connectivity for control and rmware

updates

• Balanced XLR input and output

• Three position gain switch

• Available in either 17 inch or 19 inch wide

C-Series dress panel in silver-toned (clear

anodized) or black anodized aluminum.

Shipping Box and Packing Material

Please keep the original shipping box and all
packing material. This will ensure the BAX-1 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 BAX-1 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

Ventilation

The BAX-1 is a cool-running line level component.
It generates far less heat than ampliers and many

other components. It can be safely placed inside

furniture or an equipment rack. However, it should

4

BAX-1 Active DSP Crossover

not be tightly enclosed. Some airow is desired.

Connecting to A/C Power

Please check the Data Plate on the right rear of

the crossover to verify power requirements agree
with your location. Plug the IEC-320 C14 end of the
power cord into the BAX-1, then plug the other end

into an approved and grounded A/C receptacle.

Connecting to an Audio System

Though the BAX-1 is a DSP driven digital audio
component, all audio connections are analog only.
This is to accommodate a broad range of pre-amps
and front-ends while operating the digital circuitry
at optimum conditions. Contrary to some beliefs,

converting analog to digital inside the crossover

does not create a compromised sonic experience.

From your stereo preamplier, connect the le and
right outputs to the BAX-1 le and right inputs using
good quality balanced XLR cable. The le and right

channels each have 3 outputs marked low mid
and high. The low output for each channel goes to

the amplier designated to drive the bass section,
mid should drive the midrange, and high drives the

tweeters of your speakers.

Connection Diagram

The connection diagram below shows one channel

connected of a Bryston BP-26 Preamplier → BAX­1 Crossover → 21B³ Amplier → Model T Active

Loudspeaker.

Choosing Amplication

Bryston Active Loudspeakers have been optimized

for use with Bryston ampliers however other brand
ampliers may be suitable as well. Each amplier

used must have the same gain as there is currently

no provision to compensate for mis-matched
ampliers within the DSP.

Connect to Network

Connect the BAX-1 to your network router using a
CAT-5 or better ethernet cable.

First Run

Upon rst run, the BAX-1 has not yet been

programmed for your model loudspeaker and the
power LED will blink green. You must program the

BAX-1 for your model by connecting to the web
interface. From your web browser, navigate to
http://my.bryston.com. The website will scan your
network for connected Bryston equipment and

TRIGGER

HIGH LOWMID RIGHT

WARNING

Do not connect positive
terminals to negative
terminals. Do not
connect any speaker
terminals to ground.
Risk of hazardous
energy. Make proper
speaker connections.
Use class 2 wiring.

AVERTISSEMENT

Ne connectez pas les
bornes positives aux
bornes négatives. Ne
branchez aucun
terminal d'enceinte sur
le sol. Risque d'énergie
dangereuse. Effectuez
les connexions
appropriées des

ACTIVE CROSS-OVER

TRIGGER

OUT

OUT

HIGH LOWMIDIN

LEFTIN

BAX1

TRIGGER IN

STATUS

ETHERNETUSBRS232

AC IN

MADE IN

Peterborough

FABRIQUE AU

Ontario

CANADA

5

generate a link to your BAX-1. Click that link.

Click the Terminal button. Enter the text below and
click CMD.

%2370INIT222.
The BAX-1 will respond #70INITUnlocked.

Depending on which model speaker you are pairing
with the BAX-1, enter the following:

%2370APPS_ModelT. For Model T
%2370APPS_MiddleT. For Middle T
%2370APPS_MiniT. For Mini T
%2370APP_TRex. For T Rex

The BAX-1 will restart and be ready for operation.

Bass Adjustment

Further, narrow bandwidth anomalies are less

audible than wide bandwidth anomalies. Your
focus should be correcting broadband deviations
from zero before attempting to correct narrow band
issues.

Finally, do not obsess over getting absolute at

response!

Measuring In Room Loudspeaker
Response

Though you can attempt to equalize the response
of your loudspeakers by ear, it is strongly advised

to measure the response in your room instead.

There are numerous inexpensive measurement
microphones and free soware available to

accomplish this. For those unaccustomed to

measuring loudspeakers, Bryston recommends that

your dealer do the setup and calibration for you.

Enter the DSP menu of the BAX-1. Select Pink Noise,
set the level in -dB (entering 40 results in output
40dB below full scale). Press the button “Click to

Update Source” and both loudspeakers will be
playing pink noise.

A Word About Room Tuning

The BAX-1 permits some degree of loudspeaker
tuning below approximately 150Hz. Many

competing systems provide full bandwidth

adjustments, or attempt to automatically tune

loudspeaker response based on measurements
taken by microphone. Bryston certainly advocates
tuning loudspeaker performance based on

measurements, but electrically altering loudspeaker
response is a last step, not a rst step. DSP

application is most certainly not a replacement

for proper loudspeaker placement, well informed
gear choices, proper room construction and wise
room treatment. In other words, take care to
choose upstream equipment and cables wisely, and

position your speakers carefully in the room before

attempting corrections with the BAX-1. It is for this

reason we limit the adjustment window to 9dB per
band.

Use your measurement system of choice to measure

frequency response. It may be useful to limit your
measurement band to 20-160Hz. Note the center
frequency, magnitude and width of any peaks or

dips.

Using the 10 band parametric equalizer, enable the
lters with the center frequency nearest to those

you wish to correct. Note that each EQ band can

accommodate the following adjustments: Center
Frequency can be adjusted up to 10Hz above
nominal for each band, magnitude can be -10 to
+3dB, and Q can be set between 1 and 5 where 1 is
broad and 10 is narrow. Filter changes are reected

in real time. You should both hear the changes and

see them reected in your measurements.

Monitor the graph near the bottom of the page
to see your changes. Also note that an aggregate

maximum gain of 3dB is permitted.

6

BAX-1 Active DSP Crossover

DSP Filter Setup

Bass equalization can be access through the web

user interface by clicking the DSP tab. This can be
done from the listening position from most modern

web enabled devices. See “Network Connection” on
page 10 for details on how to connect the BAX-1

to your network.

precision shown with each button press or tap.

3. Memory

Store a preset by creating a correction curve,
then pressing SAVE ALL. Reset all lters to at
by pressing RESET ALL. Recall a saved preset by
pressing RECALL ALL.

4. Audio Output

Normal function of the BAX-1 is to pass audio

received at the input jacks on the back of the
unit. You can also engage a built in sine single
tone generator and pink noise generator for
testing. Press the desired audio source then
press ‘Click to Update Source’ to engage the

1

desired audio source.

5. Peak Gain Indicator

2

3

4

5

A maximum aggregate gain of 3dB can be
achieved by the system. If two lters with
overlapping bands are engaged and maximum
gain would exceed 3dB, the 2nd lter is
restricted to a gure that maintains no more

than 3dB peak gain. Peak gain is limited to
ensure internal electronics are not creating
distortion.

1. 10 Band Parametric EQ

For each band you would like to edit, enter
desired center frequency, boost or cut in dB,
and width. Center frequency can be the preset
value or raised by up to 10Hz. Boost cut range is

-10.0 to +3.0 dB, and Q is 1.0 to 5.0 where 1 is the
widest and 10 is narrowest.

2. Increase / Decrease

Especially useful when making adjustments

from a touchscreen device, these buttons will

increase or decrease the selected value by the

6

6. Correction Curve

The result of your applied lters is indicated
in graphical form here. Ideally, this will be

the opposite of your measurements before
compensation is applied. Note that this graph is

20-160 Hz and shows -12 to +4dB

7

BAX-1 ACTIVE DSP CROSSOVER

RIGHTPOWER

LEFT

12

Front Panel

1. Power Button

Press this button to toggle the BAX-1 on or into

standby mode.

Unlit BAX-1 is not receiving power. Plug unit into

AC mains power.

Red Plugged into AC Mains but in standby

mode.

Green or

Blinking

BAX-1 is on and operational.

Blue

Secondary power supply failure. Contact

Red

Bryston technical support.

2. Audio Channel Indicators

The le and right channels both feature LEDs

which indicate the incoming audio status of
each channel.

Unlit BAX-1 is not receiving audio to the

indicated channel

Green or

Blinking

Orange

BAX-1 is receiving audio at the indicated

Blue

channel

Audio received is too loud to be processed

without distortion. Reduce preamplier

volume.

Preampliers and ampliers that do not feature

balanced audio connections can be connected

to the BAX-1 by using commonly available XLR
to RCA adapters.

Each channel also includes a trigger out jack

on a ‘mono’ 3.5mm jack which can be used

to trigger the power state of compatible

downstream ampliers. The tip is +12V and
sleeve is GND. When the BAX-1 is powered on

either by actuating the front power button or

through the trigger input, voltage is applied to

the trigger outputs.

4. RS232 Input

The BAX-1 can be controlled via two-way RS232
using a connector terminated by a 3.5mm TRS
‘stereo mini plug’. Terminate the plug as follows:
Tip: Transmit
Ring: Receive

Sleeve: Ground

5. USB Control Input

USB is provided for diagnostic information by
Bryston technicians.

Rear Panel

3. Channel Input Output

The BAX-1 includes Le and Right channel

input and output. Analog audio is received
through a balanced audio interconnect from a

stereo preamplier to the le and right channel

inputs respectively. The internal DSP divides

and processes that signal into 3 bands - low,
mid and high to drive the bass, midrange, and
high frequency amplier channels respectively.

8

6. Status LED

LED lights to indicate the following status:

Red: Standby Green: On
Amber: Starting up Blinking Amber: Updating rmware
Blue: Self programing. Do not power o

7. Ethernet Input

Ethernet connectivity is provided for user access
to a web based interface which is useful for

rmware updates and control over the internal

DSP. Discrete commands can also be sent by

custom integration systems. See page 10 for

BAX-1 Active DSP Crossover

LEFT

POWER INLET

IEC 320-C14

TRIGGER IN

STATUS

RS232

USB

ETHERNET

TRIGGER

OUT

IN

LOW

MID

HIGH

TRIGGER

OUT

BAX-1 ACTIVE DSP CROSSOVER

RIGHT

IN

LOW

MID

HIGH

5 7 8

3 9

partial documentation or the HELP tab from the

BAX-1 web interface for full documentation.

8. Trigger Input

Power/Standby can be toggled from a master
component such as a preamp using this input.

The connector is a standard 3.5mm tip sleeve
commonly referred to as a “mono mini plug”.
Signal should be AC or DC between 3 and 12
volts. When voltage is present at the tip, the BAX­1 will remain powered on. The BAX-1 powers o

when voltage is removed.

9. IEC Power Inlet:

The IEC -320 C14 power inlet accepts IEC-320
C13 equipped power cords such as the unit

provided. Use only appropriate power cords that
have been approved for your region.

10. Data Plate

The data plate is located on the bottom of

the unit. It indicates hardware version, serial
number, and A/C mains voltage of your unit.

104 6

Specifications and Dimensions

Max Voltage Input:

Output:

Frequency

20Hz - 20kHz: ± 0.1dB

Response

Noise Balanced Out:

Single Ended Out:

IMD ≤0.0003%

THD + Noise 20Hz-20kHz : ≤0.0009%

Weight 4.7kg | 10.3 lbs

Dimensions Inches: 17 or 19 W x 2.75 H x 11.11 D

Cm: 43. or 48.3 W x 7 H x 28.2 D

Power

Standby:

Consumption

at 120V/60Hz

* System operates at unity gain and only boosts or
attenuates bands as set by the user in DSP.

On:

4.0V

5.6V (+3dB)*

-140dB

-140dB

0.4W

22W

9

Network Connection

You may connect your BAX-1 to your local area
network using CAT5 or better cable to facilitate use
of the built in web-based user interface or to control

and monitor the unit using an automation system.

Once connected to the network, you may access the

web user interface with a web browser by entering
the host name into the address bar. The host name
is formatted like so where the last 6 digits are the
serial number of your unit:
http://bax1-000000

Some web browsers and networks ignore NetBIOS

names such as above. In this case, you will need to

use the numerical IP address of your unit to access

the web user interface. You can nd the IP address

by logging into your network router or with popular
network information apps on iOS and Android such
as Fing.

Installed Version

Available Version

To update the rmware:

1. Download the rmware le by clicking the
“Download Internet File...” button. Save the le

in an easy to remember location.

Firmware Update

As with many other Bryston products, the BAX-1
may receive occasional rmware updates to ensure

reliable operation and add new features. Check
your installed version and for any new updates by

using the File menu on the BAX-1 web user interface.

Internet connection must be available to show
correct information.

2. Click “Go to Choose .bin...” button. You will be
taken to a mostly blank page.

3. Click “Choose File” or “Browse”. Navigate to the

location to which you downloaded the BAX1.bin
le in step 1. This is most likely your Downloads
folder. Click the le and press “Open” or “OK”

You will be returned to the upload page. Press

the Upload button to initiate rmware upgrade.

4. Uploading takes up to 5 minutes. The power
LED will turn o during the update.

5. Do not power o. The BAX-1 will reboot itself.

You may check the web user interface to verify

that the new rmware version agrees with the

version you just downloaded. You may need to
force refresh your browser window to see any
changes.

10

BAX-1 Active DSP Crossover

Remote Control

The BAX-1 can be controlled and monitored through

a variety of mechanisms including TCP/IP when

connected to your local area network, USB, RS232,

and DC trigger.

Serial Protocol

The BAX-1 can receive commands and can send

responses to each command. It can also (optionally)
broadcast automatic responses to certain system
events such as front panel button presses.

Commands can be sent over RS232, RS485 (with an
RS232 to RS485 interface) and TCP/IP using HTTP

cmd.cgi.

The RS232 input is a 3.5mm mini-jack congured as:

Tip Ring Sleeve

Transmit Receive Ground

Command Format

RS232 # 7 D2 C1 C2 C3 C4 P1 P2

TCP/IP %23 7 D2 C1 C2 C3 C4 P1 P2

... CR

... .

Responses are returned in the same format as

commands. Note that responses may contain up

to 320 characters. All characters preceding the # or
%23 and following <CR> or . are ignored. Do not

insert #, spaces, <LF>, <TAB> or other non-ASCII
characters inside the command string.

The following are selected commands most
pertinent to initial setup and everyday operation.
Find complete documentation by accessing the

BAX-1 web UI or by contacting Bryston.

Comm. Param. Description

SDSP

Set DSP Parameters

QS or ? Display list of all FILT

command options

FILTnnfsggqq

select lter number nn(01...10),
set frequency  (030...120Hz),
set lter gain or reduction, s=1 +,
s=0 for ­set lter gain gg (00...30, 0.1dB)
set lter Q factor qq (10...50, 0.1)

The command format always begins with a
command start character.

The next two digits are the Device ID. The rst of
which is always “7” for BAX-1s, and the second will
be “0” except when using RS232/RS485 in a multi­drop conguration.

Next are C1 through C4 which comprise the

command name. These are typically uppercase
ASCII letters.

Following the command name are the arguments
or parameters for that command. These are two or
more ASCII characters.

The command is always terminated with a carriage

return character. For RS232, this is ASCII code 13.

TCP/IP commands are terminated with a
period (.)

Example:
#70MPWRQS<CR> command: query power status

MPWR

INIT

ex: #70FILT0305002530. for lter 3=50Hz,

-2.5dB, Q 3.0

FILTQS Displays last settings as

above

FILTSAVE

FILTRECALL

DSRCxx

Save lter values to EEPROM
Recall saved lter values
from EEPROM
Set DSP source xx=00 for
analog inputs, 02 for sine, 04

for pink noise

Switch between On and
Standby

00 O (standby)
01 On
02

QS

Toggle On/Standby
Query Status

Re-initialize parameters

00 Re-initialize all but TCP/IP
01 Re-initialize all inclding TCP/

IP

11

Bryston Limited | 677 Neal Drive | Peterborough, Ontario K9J 6X7

Canada | Phone: [phone] | www.bryston.com

300067-5

02-20-2018