Balanced Audio Technology VK-33SE User manual

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VK-33SE
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-33SE
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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Vacuum Tube Current Sources in VK-33SE
Your VK-33SE incorporates a unique feature that allows you to optimize its sound to tailor it to your
individual taste or system requirements.
The Vacuum Tube current sources incorporated in the VK-33SE, being part of the signal gain stage, have a
direct effect on the unit’s sound. Changing the tube type used in that circuit allows the user an extra degree
of control over the sound of the unit.
In its standard configuration the VK-33SE current sources use the Russian 6C19 tubes. That tube is
basically a miniature version of the famous 6C33 tube, and provides, in our view, the best combination of
sonic characteristics and electrical performance.
However, the unique design of the VK-33SE allows you to also use other tube types in that application.
Currently, the user has the following three choices for vacuum tube Current Sources:
1. The standard 6C19 tube current source as installed from the factory.
2. The 6H30 SuperTube current source which requires the purchase of the X-PAK accessory.
3. The 5881 tube current source.
In order to change the tube type the user needs to remove the installed Current Source board, and replace it
with either another board, designed for a particular tube type, or install the 5881 tubes as a direct plug-in.
Only the 5881 tubes can be used directly upon the removal of the 6C19 current source board.

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Please consult the factory regarding options for other tube types that may be available in the future.
WARNING:
The following procedure should only be performed by qualified personnel
To change the current source:
1. Turn the unit OFF and wait at least 5 minutes to allow the tubes to cool down and the power
supply charge to dissipate.
2. Remove the six screws holding the current source board.
3. Pull the current source board straight up to disengage its connectors.
4. Install the new current source board making sure its connectors are properly aligned. Board will
be positioned properly when the mounting holes in the circuit board align with the standoffs.
5. Install the six mounting screws.
6. Turn the unit ON.
TABLE OF CONTENT
CURRENT SOURCES 3
CHANGING CURRENT SOURCES 4
INTRODUCTION 6
Package Content 6
Physical Placement 7
Connecting to your system 7
FRONT PANEL CONTROLS 8
VK-33SE Power On sequence 8

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Turning the VK-33SE Off 8
PHASE Button and LED 9
MONO button and LED 9
MUTE button and LED 9
INPUT selection 9
VOLUME knob 9
DISPLAY format 10
FUCTION button 10
DISPLAY Brightness function 11
MUTE function 11
VK-33SE PROGRAMMABLE FUNCTIONS 12
Parameter Definitions 13
PROGRAMMING THE VK-33SE 13
BALANCE adjustment 13
VOLUME offsets 14
PHASE 15
MONO/STEREO 15
MAXIMUM gain 15
FIXED gain 16
DISPLAY MODE 16
INPUT NAME 17
REMOTE CONTROL FUNCTIONS 18
Volume Up/Down 18
Mute 18
Fade 18
Input 18
Display/Power 19
Fuse Protection 19
Servicing 19
Cleaning 19
RESETTING THE VK-33SE 20
SPECIFICATIONS 21
WARRANTY 22
INTRODUCTION
Thank you for your purchase of the Balanced Audio Technology VK-33SE
preamplifier. Please read this owner's manual to obtain the full benefit of the
VK-33SE in your system. It will provide you with the needed safety information
and operating procedures for this exceptional unit.
WARNINGS:
To prevent the possibility of serious injury, electrical shock or fire:

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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-33SE 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-33SE 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-33SE preamplifier on top of other units, nor vice
versa.
CONNECTING THE VK-33SE TO YOUR SYSTEM
Balanced Components
Use balanced XLR interconnects. All input and output connectors are clearly
marked on the back panel.
Note: The VK-33SE XLR connectors are wired as follows:
Pin 1: common/shield
Pin 2: positive
Pin 3: negative
For the VK-33SE, 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-33SE 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-33SE 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-33SE can be turned OFF by pressing and holding the Standby button.
VK-33SE Power-On sequence:
When you turn the VK-33SE 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-33SE 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-33SE OFF:

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The unit can be turned OFF by pressing and holding the Standby button. It will
automatically mute.
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-33SE 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.