User's Guide and Operating Information
™
eVo2
™
eVo4
™
eVo6
Digital Power Processor
Audio Power Amplifiers
Bel Canto Design, LTD.
212 Third Avenue North
Minneapolis, MN 55401
Phone: (612) 317.4550
Fax: (612) 359.9358
©2002-2004 Bel Canto Design, LTD
Design Features
• High efficiency Digital Power
• Damping Factor >100
Processing output stage for cool
operation
• High thermal stability in all stages
• Regulated, low noise supplies for all
analog stages
• Analog signals are processed at small
signal level, all large signal power is
generated using the switching output
stage
• Audio Grade decoupling capacitors
and resistors used throughout
• 700 watts of continuous power
output capability in Balanced
Mono mode
• Soft clipping insures graceful over
load
• High efficiency ‘green’ amplification
• Optimized balanced and single-
ended input stage
• Comprehensive protection circuitry
outside the signal path
• THD and IMD <0.05%
The eVo Digital Output Stage and Digital Power Processor
The Bel Canto Design eVo digital out-
put stage is of unique simplicity. The
output uses 2 N channel MOSFET
switches switching between the
power supply rails. These switches
turn on and off within 30 billionths of
a second and provide an onresis-
tance path to the supplies of a few
thousandths of an ohm. These
switches switch alternately between
the supplies at a rate over 600,000
cycles per second (600 kHz). When
no audio signal is present, the ratio
between the time at the positive sup-
ply and the negative is balanced to
provide no audio frequency output.
The switching stage is isolated from
the loudspeaker by a single LC filter
stage. This 80kHz second order filter
is used to reject high frequency ener-
gy and maintain linear phase
Furthermore, the digital power
processor adds small levels of high
frequency dither to insure that an
inherently linear output stage charac-
teristic is maintained from very low
to very high output levels. The audio
frequency information modulates the
output stage by changing the time
relationship between the positive and
negative supply rails. The critical
timing information is controlled by
the digital power processor and the
effective switching frequency is
changed over a 200 kHz to 1500 kHz
range. This spreads the digital ener-
gy created by the amplifier over a
wide bandwidth, greatly reducing the
energy at any one frequency. This
permits using a simple LC filter to
remove the high frequency energy
and maintains excellent phase
response.
response.
© 2002-2004 bel canto design, Ltd.
page 3
eVo User’s Guide 042104
Design Features (cont’d)
Feedback is taken before the LC filter
Warm-Up
and fed back to the digital power
processor. This feedback is used to
insure that any variations in the
switching speed of each output
device are compensated for, optimiz-
ing the linearity of the output stage.
The eVo amplifier’s sonic perform-
ance will continue to improve over
the first several weeks of operation.
Because of the very low standby
operating power we recommend
continuous power-up unless the sys-
tem is not to be used of an extended
period. This will prolong the amplifi-
er’s life and insure optimum perform-
ance at all times..
Warning!
Do not connect power to this amplifier yet!
This amplifier, like any electrical component, can be dangerous and cause injury
unless correct handling procedures are observed and used. Before powering
this amplifier it is necessary to read and follow proper setup and use procedures.
Do not open up your eVo amplifier (do not remove the chassis cover). There
are no user serviceable parts inside. Any tampering of internal parts will imme-
diately void your warranty.
Complete and mail the Owner's Registration Card immediately in order to
activate your warranty.
© 2002-2004 bel canto design, Ltd.
page 4
eVo User’s Guide 042104
Unpacking your new Evo
The box containing your eVo amplifier contains the following parts:
1 (one) - eVo audio power amplifier
1 (one) - eVo 2/4/6 User's Guide
1 (one) - Power Cable for connection to utility power [6' 7" - 2 meters long]
Carefully unpack each piece and
check for shipping damage. If there
is any damage, or if a piece is miss-
ing, please contact your dealer or Bel
Canto Design, Ltd. Save all packing
materials as the packing is specially
designed to protect the amplifier for
shipping or transporting. If you lose
or damage the packing materials or
carton, please contact your dealer or
distributor before attempting to
transport the amplifiers.
Warning!
The eVo amplifier’s
power supply is preset
for the proper national voltages
before you receive it. The power
cable will have the correct plug for
your local power system. If you
believe this is not true, please con-
tact your dealer immediately. Do
not attempt to alter or change power
settings yourself!
© 2002-2004 bel canto design, Ltd.
page 5
eVo User’s Guide 042104
Initial Setup
Please refer to the front and rear panel diagrams, as needed. [Page 8]
Line Level Inputs
Two inputs per channel are provided.
Warning:
The RCA jack is a standard input that
accepts single-ended sources. The
female XLR jack allows true balanced
hookup operation using the standard
pin configuration:
Always disconnect power
to the amplifier when
changing cables.
Pin 1 Ground
Pin 2 Input +
Pin 3 Input -
Optimizing Input Grounds
System ground optimization is criti-
cal to achieving low noise perform-
ance. This is especially critical when
using the RCA inputs.
to the power ground at the amplifier.
Try connecting the RCA ground to
chassis ground by depressing the
RCA/XLR switch button (RCA posi-
tion). If this button is depressed and
there is ground noise or hum then try
setting this switch in the XLR posi-
tion.
The XLR/RCA switch is used to opti-
mize the grounding at the amplifier
inputs. Setting the XLR/RCA switch in
the RCA position connects the RCA
ground to the chassis and the power
cable.
Putting this switch in the XLR posi-
tion effectively lifts the RCA ground
on the amplifier input and can pre-
vent ground loop noise. This is espe-
cially useful for systems using more
than one amplifier chassis or when
using the eVo4 or eVo6 amplifiers in
a system.
If using Balanced XLR cables then
leave the switch in the XLR position,
otherwise the negative XLR input will
be shorted to the amplifier ground.
If using the RCA inputs and the
Preamplifier has a floating ground
then using the RCA switch position
will give the lowest noise operation.
This will connect the system ground
These procedures should be ade-
quate to correctly ground most
systems.
© 2002-2004 bel canto design, Ltd.
page 6
eVo User’s Guide 042104
Loudspeaker Connection and Power Output Options
post until the center plug comes out.
Warning!
Do not connect speaker terminals to
a chassis or earth ground connection.
The Anti-Phase operation of the out-
puts would result in one of the active
outputs being connected to ground
and cause the amplifier to go into
protection mode and shut itself off.
Also when connecting the amplifier
in balanced-mode mono operation
both terminals are driven actively
and can not be grounded.
Make certain that any
output terminal is not connected to a
chassis or earth ground.
Connect loudspeakers to the outputs
of the eVo amplifier using the 5-way
binding posts located on the rear of
the amplifier. The red or black center
plug in the output post can be
removed for use with banana type
connectors. Unscrew the binding
Balanced Mono Mode Operation
High-power balanced mono operation
can be obtained with the simple push
of a button. Connect one input cable to
any of the 4 input jacks on an eVo2 or
input jack sets on an eVo4 or eVo6.
Then depress the MONO/STEREO
mode button. Connect the loudspeaker
to the output terminals indicated for
mono-mode operation on the back
panel.
© 2002-2004 bel canto design, Ltd.
page 7
eVo User’s Guide 042104
Power On and Operation
The front panel switch or rear panel
12 volt trigger input is used to power
on the amplifier. When using the 12
volt trigger the front panel switch
should remain in the off (out) posi-
tion. The eVo amplifiers have been
designed to remain powered up at all
times, their very low standby power
is conducive to this. The blue front
panel LED remains on when the eVo
is in normal operating mode. When
the amplifier shuts down in protec-
tion mode a small red LED lights next
to the front panel power switch. If
this occurs, remove power and
insure that no output terminal is con-
nected to ground or to another termi-
nal. Restore power and the amplifier
should return to normal operation.
If not then there may be an internal
fault and the amplifier should be
returned to an authorized service
center. Contact your dealer, distribu-
tor or Bel Canto Design.
eVo2
eVo4
eVo6
© 2002-2004 bel canto design, Ltd.
page 8
eVo User’s Guide 042104
Amplifier Placement
We do not recommend placing
weights or other objects directly on
the eVo. This may mar or scratch the
chassis finish. Dampen a soft cotton
cloth with warm water for cleaning
the outer surfaces.
eVo Amplifier Placement
Within Your System
The most typical arrangement places
the eVo on the lower shelf of a rack
or shelf unit; some users prefer to
have the eVo on its own stand.
Because the eVo runs so cool it can
be placed in many system locations
without compromise.
Specifications
eVo2
eVo4
eVo6
Output power
@ 8 Ohms
2 Ch.
120 W
240 W
23dB
1 Ch.
400 W
700 W
29dB
4 Ch.
120 W
240 W
23dB
2 Ch.
400 W
600 W
29dB
6 Ch.
120 W
240 W
23dB
3 Ch.
360 W
600 W
29dB
@ 4 Ohms
Gain
Bandwidth
1Hz -80KHz ˇ3dB
1Hz -80KHz ˇ3dB
< 0.05% THD at 1WRMS
>100, below 100Hz
100k/200k Bal
1Hz -80KHz ˇ3dB
< 0.05% THD at 1WRMS
>100, below 100Hz
100k/200k Bal
THD and Noise
Damping Factor
Input Impedance
Inputs
< 0.05% THD at 1WRMS
>100, below 100Hz
100k/200k Bal
XLR & RCA
XLR & RCA
XLR & RCA
Outputs
2 pr. 5-Way
4 pr. 5-Way
6 pr. 5-Way
Ide Power Draw
Dimensions-inches WxDxH
Dimensions-mm WxDxH
Weight
15 Watts
30 Watts
45 Watts
17.5 in x 14.5 in x 4.5 in
44.5 cm x 37 cm x 11.5 cm
36 lbs (14.5 kg)
17.5 in x 18.5 in x 4.5 in
44.5 cm x 47 cm x 11.5 cm
40 lbs (18kg)
17.5 in x 18.5 in x 4.5 in
44.5 cm x 47 cm x 11.5 cm
42 lbs (19 kg)
Features and specifications are subject to improvements and changes without prior notice.
© 2002-2004 bel canto design, Ltd.
page 9
eVo User’s Guide 042104
Bel Canto Design, LTD.
212 Third Avenue North
Minneapolis, MN 55401
Phone: (612) 317.4550
Fax: (612) 359.9358
©2002-2004 Bel Canto Design, LTD
eVo™ is a trademark of Bel Canto Design, LTD
|