Balanced Audio Technology VK-33 User manual

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VK-33
WARRANTY REGISTRATION FORM
Unit Serial Number:
_______________________________________
Customer Name:
_______________________________________
Address:
_______________________________________
_______________________________________
Date of Purchase:
_______________________________________
Purchased From:
Dealer Name:
_______________________________________
Address:
_______________________________________
_______________________________________
IMPORTANT NOTE:

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In order to receive the full five year product warranty, please
mail this completed form together with a copy of your sales
receipt to Balanced Audio Technology at the address below,
within thirty days of purchase.
Failure to do so will result in the product being warrantied for
one year from the date of manufacture.
1300 First Stat Blvd. Suite A Wilmington DE 19804 Tel: [phone] Fax: 302-999-
8818

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VK-33
Vacuum Tube
Balanced Stereo Preamplifier
Owner's Manual
1300 First Stat Blvd. Suite A Wilmington DE 19804 Tel: [phone] Fax: 302-999-
8818

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TABLE OF CONTENT
INTRODUCTION 4
Package Content 4
Physical Placement 5
Connecting to your system 5
FRONT PANEL CONTROLS 6
VK-33 Power On sequence 6
Turning the VK-33 Off 6
PHASE Button and LED 7
MONO button and LED 7
MUTE button and LED 7
INPUT selection 7
VOLUME knob 7
DISPLAY format 8
FUCTION button 8
DISPLAY Brightness function 9
MUTE function 9
VK-33 PROGRAMMABLE FUNCTIONS 10
Parameter Definitions 11
PROGRAMMING THE VK-33 11
BALANCE adjustment 11
VOLUME offsets 12
PHASE 13
MONO/STEREO 13
MAXIMUM gain 13
FIXED gain 14
DISPLAY MODE 14
INPUT NAME 15
REMOTE CONTROL FUNCTIONS 16
Volume Up/Down 16
Mute 16
Fade 16
Input 17
Display/Power 17
Fuse Protection 17
Servicing 17
Cleaning 17
RESETTING VK-33 18
Warranty 19
INTRODUCTION
Thank you for your purchase of the Balanced Audio Technology VK-33
preamplifier. Please read this owner's manual to obtain the full benefit of the
VK-33 in your system. It will provide you with the needed safety information
and operating procedures for this exceptional unit.

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WARNINGS:
To prevent the possibility of serious injury, electrical shock or fire:
DO NOT operate with the cover removed.
DO NOT expose to rain or moisture.
DO NOT defeat the ground power-plug.
DO NOT replace fuse with anything other than the same type and rating as supplied
by the factory.
Package Contents
Included in the box should be the following:
Description Quantity
VK-33 Preamplifier 1
Power Cord 1
Spare Fuse 1
Torx Wrench (T-15) 1
Spare Top Cover Screws 5
User’s Manual 1
VK-R3 Remote Control (If ordered)
Save all the packaging material in a safe dry area for the unlikely event that
you need to return the VK-33 to the factory for service.

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PHYSICAL PLACEMENT
It is recommended that you provide at least 6" of free space around the unit for
proper ventilation.
Mount the unit on a hard surface with proper ventilation underneath.
Do not stack the VK-33 preamplifier on top of other units, nor vice versa.
CONNECTING THE VK-33 TO YOUR SYSTEM
Balanced Components
Use balanced XLR interconnects. All input and output connectors are clearly
marked on the back panel.
Note: The VK-33 XLR connectors are wired as follows:
Pin 1: common/shield
Pin 2: positive
Pin 3: negative
For the VK-33, use the Main 1 XLR Output for connection to your balanced power
amplifier. The Output 2 is configured as an RCA connector output.
Single-Ended Components
Single-ended components have RCA connectors. The VK-33 preamplifier is
designed to work with mix of single-ended and balanced components connected
to its inputs and outputs. If more single ended components need to be
connected to the preamplifer, then the XLR inputs or outputs can be used for
that in conjunction with RCA/XLR adapters. These adapters are available from an
authorized Balanced Audio Technology dealer at a nominal charge.
Two types of adapters are available:
Input Adapters: RCA Female to XLR Male
Output Adapters: RCA Female to XLR Female.

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VK-33 FRONT PANEL CONTROLS
STANDBY Button and LED
The Standby button is used to turn the unit ON and OFF and to switch the
preamplifier into its Standby mode. The LED indicates the status of the unit’s
power circuitry and has four state:
LED OFF Display OFF Unit is in OFF state
Display ON Unit is in ON state
LED Flashing Unit is going through its Power-ON routine
LED ON Unit is in its STANDBY mode
When the unit is plugged into a power line, it will stay in the OFF state until the
Standby button is pushed. The LED will then start blinking and the unit will go
through a 50second warm-up sequence. At the end of that sequence it will turn
ON.
Pressing the button again will switch the unit into its Standby mode.
The VK-33 can be turned OFF by pressing and holding the Standby button.
VK-33 Power-On sequence:
When you turn the VK-33 On, it will automatically go through a gentle power-on
sequence. This sequence takes 50 seconds, during which time the display and
the Standby LED will be flashing, indicating the status of the unit.
1. The number on the display during this time indicates the volume setting.
This will usually start at 000. This setting can be changed during this time
by using the volume knob or Volume Up/Down buttons on your VK-R3
remote control transmitter. In addition, such functions as Phase, Mono,
input selection and Mute can be changed during this time either from front
panel or through the remote control.
2. Normally the VK-33 will be not muted (Mute LED on the display is OFF) and
will begin playing at the end of the 50 second delay. If so desired, the unit
can be put in the MUTE mode during this delay interval either by depressing
the front panel MUTE switch or by using the MUTE button on the VK-R3
remote control transmitter.
Turning the VK-33 Off:
The unit can be turned OFF by pressing and holding the Standby button. It will
automatically mute.

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PHASE button and LED
This button allows the user to invert the absolute polarity of the signal to
compensate for some recordings that are made out-of-phase. The LED indicates
whether the unit is in its INVERTING or NONINVERTING mode. This function is also
accessible via the VK-R3 remote control.
LED OFF Non Inverting operation
LED ON Inverting operation
MONO Button and LED
The Mono button allows the user to switch the VK-33 in Mono operation when the
two channels are summed together. This may be useful, for example, while
listening to old monophonic recordings. This function is also accessible via the VK-
R3 remote control.
LED OFF Stereo operation
LED ON Mono operation
MUTE Button and LED
The Mute button disables the preamplifier output. It is recommended that the
Mute be engaged any time the signal cables are changed or any other system
configuration changes are being made. This function is also accessible via the VK-
R3 remote control.
LED OFF Unit in Play mode
LED ON Output Muted
INPUT selection buttons 1through 5
These allow the user to select any of five available inputs to be played. The
selected input number together with its name will be indicated on the unit front
panel display as well. This function is also accessible via the VK-R3 remote
control.
VOLUME Knob
This knob performs different function depending upon the unit’s mode of
operation. In normal mode it works as volume control knob.
It is also used as a data input device in various Function modes to program the
unit. For example, it is used to set the BALANCE adjustment when the VK-33 is

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switched into its Balance mode. More on that in the corresponding sections of
this manual.
The volume control knob on the VK-33 is linked to a digital encoder and is of a
continuously rotating type (there are no stops).
DISPLAY FORMAT:
The VK-33 Vacuum Fluorescent Display (VFD) is capable of showing up to twelve
alphanumeric characters. Its format depends on the mode of operation. In the
normal PLAY mode the display has the following format:
1. One character indicating the selected input number.
2. Four-character input name. That name is fully programmable (See the
programming functions) and can include up to four character from the
Latin, Cyrillic or Greek alphabets or digits.
3. Balance adjustment indicator. Characters L or R indicate that the balance is
shifted in the corresponding direction. A BLANK character means that the
gains of both channels are identical.
4. Volume setting - three digits with the full range of 000 to 140 (See
programming section on Maximum Volume Setting)
FUNCTION Button
This button puts the unit in its programming mode. In addition to its normal PLAY
mode, there are eight programmable functions in the VK-33:
BALANCE Adjustment
RELATIVE VOLUME setting
PHASE setting
MONO/STEREO setting
MAXIMUM volume setting
FIXED volume setting
DISPLAY (Volume) mode
INPUT NAME assignment
Pressing this button while in PLAY mode will switch the unit into programming
mode. Once in the programming mode, pressing the Function button will switch
the unit into its NEXT programmable functions. The unit will stay in the
programming mode until the exit command is issued. To EXIT the programming
mode at any time, press and hold the Function button for about TWO seconds.

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DISPLAY Brightness Function
Changing the Display Brightness: The VK-33 display can be dimmed
or turned completely OFF by simply pressing the DISPLAY button on your
VK-R3 remote control transmitter.
Each press will reduce the brightness of display and LED indicators in steps
from full ON to OFF, and then one press back to full ON. The LED indicators
will dim but never turn completely OFF. With the display OFF, issuing any
remote control command that would normally require a display change (i.e.:
Volume, Input selection, Fade) will automatically turn the display back ON.
MUTE Function:
The VK-33 has two mute modes: manual and automatic. The blue LED above the
Mute button goes ON when the unit is in MUTE state. To MUTE the VK-33,
depress the MUTE button located on the right side of the front panel. Depressing
this button again will return the unit to its normal operation and turn the mute
LED off.
When the unit is powered up it automatically self-mutes until the proper operating
points of the circuitry are reached. It will then automatically go into Play mode,
provided the Mute function was not activated (the blue Mute LED is Off).
Turning the VK-33 OFF even for short time, will make the unit reset its power
sequencing circuit and mute its output. It will then require 50 seconds for the
unit to become operational again.