VTL TL2.5 User manual
VTL
TL2.5 Line Stage Preamplifier
Owner’s Manual
MAKING TUBES USER FRIENDLY
VTL TL2.5 Preamplifier
Information in this document is subject to change without notice. No part of this document may be
reproduced or transmitted in any form or by any means, electronic or mechanical, for any purpose, without the
express written permission by VTL.
Version History:
Version 5.0 March 24, 2009
Part Number: OM-0490
Copyright ©2009 by VTL Amplifiers Inc. All rights reserved.
4774 Murrieta Street, Suite 10
Chino, CA 91710, USA
Phone 909.627.5944 • Fax 909.627.6988
Table of Contents
CHAPTER 1 ...............................................................................................................................1
INTRODUCTION ..........................................................................................................................1
Electrical Safety Notice..........................................................................................................1
Water and Moisture ...............................................................................................................1
Location and Ventilation........................................................................................................2
Servicing ................................................................................................................................2
CHAPTER 2 ...............................................................................................................................3
GETTING STARTED.....................................................................................................................3
TL 2.5 Front Panel Controls..................................................................................................3
The Preamplifier’s Back Panel..............................................................................................5
The Remote Control Hand-held Unit.....................................................................................6
Fitting the Batteries to the Remote Control...........................................................................6
Connecting Your Preamplifier to your system.......................................................................7
Powering your system on.......................................................................................................9
Using the Preamplifier with the Remote Control...................................................................9
Powering the system off .......................................................................................................10
CHAPTER 3 .............................................................................................................................11
OPERATING THE PREAMPLIFIER ...............................................................................................11
Connecting and Selecting Source Components....................................................................11
Power On Stages..................................................................................................................11
Connecting the TL2.5 to a Home Theater System................................................................11
Using the Tape Loop to monitor recordings........................................................................12
Connecting a second pair of amplifiers...............................................................................13
Connecting to the Turntable ................................................................................................13
CHAPTER 4 .............................................................................................................................16
CARE AND MAINTENANCE OF YOUR VTL PREAMPLIFIER.........................................................16
BREAK IN PERIOD ....................................................................................................................16
Tube Life ..............................................................................................................................16
Changing Tubes...................................................................................................................17
Changing the Main Fuse......................................................................................................19
Cleaning...............................................................................................................................20
Troubleshooting...................................................................................................................20
CHAPTER 5 .............................................................................................................................23
SPECIFICATIONS.......................................................................................................................23
TL2.5 Preamplifier Owner’s Manual
VTL i
CHAPTER 6.............................................................................................................................24
WARRANTY .............................................................................................................................24
APPENDIX...............................................................................................................................25
Warranty Registration .........................................................................................................25
Service Notes........................................................................................................................25
TL2.5 Preamplifier Owner’s Manual
VTL ii
CHAPTER 1
Introduction
Congratulations on your purchase of a VTL pure tube preamplifier.
his hand crafted equipment is designed to deliver superb performance for
your listening pleasure for many years to come. Please take a moment to read
through this owner’s manual. You will get an idea of the installation
procedures needed to connect this preamplifier to the rest of your audio
system, as well as the various functionality this preamplifier can perform. Please take
enough time to get familiar with the features of this product. After you have finished
reading this manual please keep it in a safe place for future reference.
T
The VTL team is proud that you have selected our pure tube preamplifier as a new
member of your home audio system. This preamplifier is designed to give you the
convenience and flexibility to manage all your audio and video sources while at the
same time giving you the musical experience that is the most alive and the truest to
your source, and we hope you’ll get many hours of enjoyment from it.
Electrical Safety Notice
Electrical voltage from power cables is hazardous. We recommend that the power
cord connected to this unit be used with a properly grounded outlet. To prevent
electrical shock do not remove the cover of this preamplifier while the unit is powered
on.
Prior to connecting this preamplifier to any audio or video equipment in your system,
make sure this unit’s power (and the rest of the equipment connected to its input and
output channels) is turned off. Adding or removing input or output cables to the
preamplifier while the system is powered on can cause damage to the system.
Water and Moisture
The preamplifier should be used away from water or moisture. If liquid enters the
preamplifier it must be immediately returned to your dealer for servicing. In this case
you should under no circumstances try to power the unit on - there are hazardous
voltages present in this unit that can cause serious injury if they come in contact with
you.
TL2.5 Preamplifier Owner’s Manual
VTL 1
Location and Ventilation
Install this preamplifier in a location which is stable and well ventilated. If the
preamplifier is placed in a built-in installation, ensure that there is adequate room for a
supply of air to flow through the ventilation openings. Allow at least 3 - 5 inches
clearance on the top and around the sides of the preamplifier. Be sure the preamplifier
is at least 10 inches away from your amplifier to prevent possible noise introduction
into your system. Tiptoes or other isolation accessories may prove useful in reducing
mechanical vibrations. Do not place the preamplifier next to heat sources such as
radiators, stoves or other appliances. Do not place preamplifier on the floor where
small children can tamper with the equipment. If it is not possible to place
preamplifier out of the reach of small children it is recommended that you remove
power cables when the equipment is not in use.
Servicing
Do not attempt to service the preamplifier beyond the procedures described in this
manual. For all other service and questions, please contact your authorized VTL
dealer or the factory.
TL2.5 Preamplifier Owner’s Manual
VTL 2
CHAPTER 2
Getting Started
After you open the carton you should find the following items inside:
• The preamplifier, with a power cord
• The remote control hand-held unit with two AA batteries
• This User Manual, VTL Quality Assurance test document, VTL product warranty
registration card
Remove each item from its packaging material and check to make sure that no physical
damage has occurred during shipping of the unit. There should be no rattles inside
either of the preamplifier or remote control units. Look through the vent slots and
check to see that the tubes appear properly seated firmly in their sockets. Contact your
VTL dealer immediately if physical damage is detected.
TL 2.5 Front Panel Controls
TL2.5 Preamplifier Owner’s Manual
VTL 3
You can operate the various controls and switches from the front panel to access the
full functionality of the unit. The Status indication LED shows the various operating
modes of the unit.
The Status LED indicates the power on status of the preamplifier. When the unit
is powered on, the LED light will first blink to indicate the preamplifier is in mute,
and then after 30 seconds, the blinking will go away. The Status light continues to
stay on to indicate that the system is in the “ready” state.
The Input Selector can be used to select the source component for the preamplifier.
You can choose any one of the six inputs by turning the selector knob to the
location as marked above the knob.
The Tape Monitor can be used to select whether the input source is coming from
tape monitor or not. If you wish to use the preamplifier to monitor an ongoing
recording session from the tape deck, you can select this switch to Tape Monitor
mode. In this state the playback from the preamplifier will come directly from the
tape deck. In the default operating mode of the preamp, this switch stays n the
down position. This means that the input source will not come from the tape deck,
but will be dependent on the input selection made on the preamplifier.
The Surround Processor:This switch can be used to change the control of your
audio/video system to the surround processor when the switch is turned to the
Processor In position. In this mode, the surround system will only control all of the
channels of your system, and the preamplifier is in the unity gain mode. In this
mode the volume control and the amplification stages of the TL2.5 are bypassed
completely, and the signal is passed to the front left and right amplifiers at precisely
the same volume as the surround processor is putting out. In the default operating
mode of the preamp, the Processor switch stays in the down position. This means
that the preamplifier will not be receiving the signal from the surround processor.
The Balance Control knob can be used to set the left and right channel level. When
the line on the knob is in the 12 o’clock position this indicates that the left and
right channels are equally balanced - you will feel a center detent in the control to
indicate this exact position.
The Volume Control knob changes the loudness level of the output from your
speaker system. Turning the knob clockwise will increase the volume level.
Alternatively, turning the knob counter-clockwise will decrease the volume level.
The Mute switch is a momentary toggle switch to allow you to switch the system
into the mute state if the preamplifier is currently in the operating state - press the
switch down. If the preamplifier is currently in mute state, clicking this switch
down again will change the system back into the operating state.
TL2.5 Preamplifier Owner’s Manual
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The Status LED indicates whether the preamplifier is in operating state or in muted
state. When the LED light is on, the preamplifier is in operating state. When the
LED light is on and flashing, the preamplifier is in mute state. The LED is off
when the system is powered off.
The Remote Receiver window allows the transmission of signal from the remote
hand-held unit to be received by the preamplifier. Keep this window clear from
any obstruction to allow maximum signal transmission.
The Power On/Off switch can be used to turn the preamplifier on and off. Press
the switch up to turn the preamplifier ON and press the switch down to turn the
unit OFF. The Status LED should be on and off respectively, according to the
setting of the Power On switch.
The Preamplifier’s Back Panel
From the Preamplifier’s back panel, you can access the input, output, ground and
power connectors, the main fuse holder, and the serial number of the unit.
GND
Left
Right
Manufactured by:
TL 2.5 Stereo Preamplifier
VTL Amplifiers Inc.
4774 Murrieta Street Suite 10
Chino, CA 91710 USA
(909) 627-5944
For continuous protection
against fire hazard replace only
with fuse of same type and rating.
To prevent electric shock do not remove cover. No user serviceable parts inside.
Refer servicing to qualified personnel. To prevent fireor shock do not expose this appliance to rain or moisture.
Phono/Aux 2
Aux 1
CD
Tape
Tuner
Video
In
Tape
OutIn
Outputs Processor
BA
Inputs
1 A Slo Blo (120V)
.4 A Slo Blo (240V)
FUSE
Main Fuse Serial Number and
Model Number Tag
AC Power Connector Preamplifier Outputs Processor Inputs Tape Monitor
Inputs and Outputs Line Stage Inputs Phono Stage
Input Phono Ground
Connector
TL2.5 Preamplifier Owner’s Manual
VTL 5
The Remote Control Hand-held Unit
The Remote Control hand held unit which comes with this TL2.5, allows you to
perform some basic functions from the comfort of your seat:
• Increase/decrease the Volume Control by pressing the up and down
arrows respectively on the remote control hand-held unit.
• Set the system in mute or operate modes by pressing the
mute button on the remote control hand-held unit. This
is a toggle control that changes the operating state from
one to the other each time it is pressed.
pure tube
VOLUME MUTE
REMOTE NP-2
If the TL2.5 is in mute, pressing the up arrow to increase the
volume will remove the mute to allow you to hear the change
of the volume adjustment. The volume down command will
not change the mute state.
When you first press the buttons on the remote control unit,
there is a delay of a few seconds (about 1-2 seconds) before
the TL2.5’s completes the processing of the signal sent by the
remote. Wait for the response from the TL2.5 before pressing
another button on the remote unit. During this processing
period, selection of other remote functions will be ignored. If
more of one button is pressed at once then the remote will
perform no function. While the TL2.5 is in the warm up
mode, with the LED blinking, the TL2.5 will not be able to
react to commands from the hand held remote.
Fitting the Batteries to the Remote
Control
1. The back cover of the remote control is a sliding cover
that is removable by pressing down on the arrow and
sliding the cover off in the direction of the arrow to reveal
the battery compartment. Remove the cover and put it
aside for re-installation later.
2. Locate the battery holder and insert the two AA batteries (supplied) in the
marked positions, + to + and - to -.
TL2.5 Preamplifier Owner’s Manual
VTL 6
3. Being careful not to damage the cover or the remote shell, replace the
back cover and slide it back into position with a snap.
4. After power up of the TL2.5, test the remote control functions and ensure
that all the functions are working correctly. If the functions are not
working then check that the batteries are in the correct mounting positions
and that they are not stale. If you still encounter problems then you
should call the VTL factory or your VTL dealer.
Connecting Your Preamplifier to your system
TL2.5 Preamplifier Owner’s Manual
VTL 7
1. Connect all source components (e.g. CD, Tuner, Tape, DAT, Video Player etc.)
to the inputs on the preamplifier. For example, connect the output cables from
the CD transport to the CD input connectors of the preamplifier. Make sure that
the preamplifier and the source components are powered off. Use appropriate
interconnects for the different sources. If a direction indicator is printed on the
cable make sure that the cable is connected to the source and the preamplifier in
the appropriate direction (arrows flowing in the direction the signal will travel, ie.
from the source to the preamplifier.) It is also important that the left and right
channels from the source components are connected to the corresponding left and
right channels of the preamplifier.
2. Connect the power amplifier to the output channel of the preamplifier. The
interconnect cable between the amplifier and the preamplifier links the left and
right input channels of the power amplifier to the left and right output channels of
the preamplifier. The low output impedance of the preamplifier is capable of
supporting long interconnects up to 35 feet, and can also easily drive transistor
amplifiers. There are two sets of output connectors available from the
preamplifier so that a second pair of amplifiers can be connected to the system.
The second pair can either be used for bi-amping or to drive a subwoofer in the
system. When connecting more than one pair of amplifiers in parallel it is advised
that you be aware of the different input impedance, sensitivities and resultant input
impedance. If you have any questions about this then you should contact either
you dealer or the manufacturers of your amplifiers, or contact the VTL factory
service department.
3. Connect the Surround Sound Processor to the preamplifier. To take advantage
of the Surround Processor loop capability, connect the Right and Left output of the
Home Theater processor to the Processor In on the preamplifier.
4. Connect the Tape Monitor input and output channels to the preamplifier. To
take advantage of the Tape Monitor capability, connect the Tape Out on your tape
deck to the Tape In on the preamplifier and connect the Tape Out on the
preamplifier to the Record In on your tape deck.
5. Connect the Phono stage to the preamplifier. If your preamplifier comes with
the optional phono board, you can connect the output from your turntable to the
Phono/Aux 2 input channel of the preamplifier. Use the Ground connector on the
preamplifier so that you can insert the ground wire from the turntable into the
space between the connector and chassis. Be sure to tighten the Ground connector
and make sure that it makes a firm contact with the wire.
TL2.5 Preamplifier Owner’s Manual
VTL 8
Powering your system on
After you have properly connected all your source and amplifier components to the
preamplifier you are ready to power your system on.
1. If you haven’t already done so, ensure that all the tubes inside the VTL
preamplifier are properly seated all the way into their sockets before connecting
the unit to an AC source.
2. Power on the source component(s) you intend to use for your listening session
3. From the preamplifier’s front panel Power On switch turn on the preamplifier.
Check to make sure that the Status LED indicates preamplifier warm up mode, as
indicated by the flashing Status LED. Check to ensure that the volume control is at
the minimum or desired level.
4. Once the preamplifier completes its warm up cycle the Status LED will stop
flashing to indicate that it has returned from the mute state into the operating state.
In case the Status LED do not behave as described above check to make sure that
the power cable is securely connected to the AC Power connector in the back
panel of the preamplifier, and that the power cable is plugged into the AC supply.
Contact your VTL dealer if the unit still will not power up after these checks have
been performed.
5. Adjust the Input Selector to the input source you would like to use. Make sure the
Tape Monitor and Surround Processor In switches are in default state (down
position) if you’re not utilizing these features.
6. Turn on the power amplifier(s) in your system.
7. Set the source component to play mode.
8. Turn up the volume control to the desired playing level. If the preamplifier is in
mute, (i.e. the Status LED is flashing), flip the mute switch again to reset the
system out of mute and into operating mode.
Using the Preamplifier with the Remote Control
1. Follow the power on sequence steps 1 to 4 as described in the previous section.
2. Refer to page 6 Fitting the Batteries to the Remote Control section for battery
installation instructions.
TL2.5 Preamplifier Owner’s Manual
VTL 9
3. Use the remote control’s volume button to adjust the desired playing level.
Increase the volume by pressing the up arrow button on the remote control.
Decrease the volume by pressing the down arrow button on the remote control.
4. If the system is in mute, (i.e. the Status LED on the preamplifier’s front panel is
flashing), press the round mute button on the remote control to reset the system
out of mute mode and put it into operating mode. Note that pressing the
volume up arrow on the remote control unit will also reset the system out of
mute mode. On the other hand, pressing the volume down arrow will not
affect the mute/operating state of the preamplifier.
Powering the system off
1. When you’re done listening to your system always turn your power amplifier(s) off
first. Allow a short time (15 - 20 seconds) for the amplifier(s) to power down after
you turn them off.
2. Then turn the preamplifier volume down. This is a precaution to avoid a sudden
surge in your system the next time you turn it on.
3. Turn the preamplifier and source components off, if you prefer to keep these off
when not in use. (You may keep your VTL preamplifier and your source
components on permanently if you prefer to keep them warm.)
TL2.5 Preamplifier Owner’s Manual
VTL 10
CHAPTER 3
Operating the Preamplifier
Connecting and Selecting Source Components
The Input Selection for the preamplifier is marked for Video, Tuner, Tape, CD,
Auxillary and Phono source components. The input connectors on the back panel of
the preamplifier are correspondingly marked Video, Tuner, Tape, CD, Auxillary and
Phono. Be sure to connect the proper interconnect cable from the source component
to the corresponding input connector of the preamplifier and in the correct channels.
If your preamplifier does not come with the phono option then you can also use
Phono/Aux2 as an additional input for any source you wish to use, including a separate
external phono stage that can produce a line level signal.
If you have installed the optional phono stage for your preamplifier the Phono/Aux2
input connector should be reserved exclusively for the phono input from your
turntable. Do not connect any other input sources to this connector.
Power On Stages
When you first power-on your preamplifier it goes through a warm-up stage which
takes approximately 50 seconds. During this period the preamplifier is in the muted
mode, as indicated by the blinking Status LED. After the warm-up stage is completed
the preamplifier automatically goes into the operating state. The Status LED turns
into a steady green light, indicating that the preamplifier is ready for use.
Connecting the TL2.5 to a Home Theater System
Your VTL TL2.5 integrated amplifier is designed to work in conjunction with
both the conventional two-channel and the home theater systems. If you have
both systems set up so that your front speakers are used for your audio as well as
home theater systems, then connect the external surround processor front left and
right main outputs to the TL2.5 Processor In input, so that it will be able up to drive
the front left and right speakers when the processor loop is engaged.
Under this configuration, when you are listening to your two-channel audio
system from sources connected to the line inputs of the TL2.5 set the Processor
TL2.5 Preamplifier Owner’s Manual
VTL 11
switch on the TL2.5 front panel to the default operating position (down). The
source components and the TL2.5 are now driving the front speakers, giving you
the full volume control and source selection.
When you want to use your system for home theater, set the TL2.5’s Processor
switch to the Processor position (up). Under this configuration the TL2.5 receives
the external surround processor's signal for the front left and right channels
directly from the external surround processor, and passes it directly to the power
amplifiers without amplification or attenuation. This means that in this mode the
volume control and the amplification stages of the TL2.5 are bypassed completely,
and the signal is passed to the front left and right amplifiers at precisely the same
volume as the surround processor is putting out. This gives the external surround
processor the volume control of these channels while controlling the center, rear
and subwoofer channels at the same time.
Caution: Before switching the Processor switch to either the up
or down position ensure that you adjust the volume of the
TL2.5 and the surround processor to a low level to protect your
system from high signals that might come through.
Caution: If you do not have a surround processor connected to
the TL2.5’s Processor In input, you may get a slight buzzing
sound when you set the Processor switch to the up position,
which comes from the open input of the power amplifier. This
slight buzz will not damage anything in your system.
Using the Tape Loop to monitor recordings
If you use a tape deck that gives you the capability of monitoring the recording, i.e.
listening to the recording while it is taking place, you can use the TL2.5’s Tape Loop
switch to take advantage of this feature. Connect the tape’s input and output cables to
the TL2.5’s Tape Out and Tape In connectors, respectively, as per the instructions in
the Getting Started section of this manual. While the tape deck is in recording mode, set
the preamplifier to Tape mode (switch in the up position.) This allows the preamplifier
to play back the recording simultaneously while the tape is recording. The volume of
the Tape monitor input is regulated by the main volume control on the TL2.5 in this
mode.
Caution: Before engaging the Tape monitor switch be sure to turn
the volume control all the way down. If your tape deck does not
have a monitor feature (sometimes called a 3rd head), then
connecting to the TL2.5’s Tape Loop may result in a loud hum
through the system whenever the Tape Loop switch is engaged.
TL2.5 Preamplifier Owner’s Manual
VTL 12
In this case the output from the tape deck should be connected to
the regular line input marked Tape in the main input cluster on the
TL2.5.
This loud hum will not damage your TL2.5, but may damage other
components in the system if sufficiently loud enough.
Connecting a second pair of amplifiers
If you wish to use two pairs of amplifiers to drive your loudspeakers in a bi-amplified
mode you can connect the amplifiers to each of the two outputs of the preamplifier.
One pair would go to Output A and the other to Output B on the back panel of the
preamplifier.
Consult your speaker and amplifier manuals for additional installation instructions on
this mode of usage. Your dealer should also be able to give you guidance with this
procedure.
Connecting to the Turntable
If your TL2.5 Preamplifier is equipped with the optional internally retrofittable phono
stage, you can use the phono stage with either MM or MC cartridge. The VTL factory
standardly configures the TL2.5 phono stage to work with a MM cartridge. If you would
like to alter the standard setting, please follow the instructions below or contact your dealer
for assistance. The following drawing shows the location of the 12AX7 tubes used in the
phono stage. The 12AX7 tube used in location V2 is for the MC stage only and should be
of the type 12AX7 JJ, a tube with higher gain than the 12AX7s used in the MM stage in
locations V1 and V101.
TL2.5 Preamplifier Owner’s Manual
VTL 13
+
+
+
++
+
+
+
+
R9
R109
C6
QC:
TEST:
+
+
+
FIL
FIL GND
B+
B+ GND
PCBA: 320-0628
PCB:360-0625-200VER2.0
U1
C6A
C106A
R8
R108
C9 C8
R1
R2
R4
R3
R101R102
R103
R104
R5
R6
R105
R106
R7
R107
R10
R12
R110 R112
R113 R13
R14
R14B
R13B
R17
R117
C106
C108
C109
C9A
C2
OUT
RIGHT
C109A
OUT
LEFT
C102
R114
C105
C101
R114B
C104
R113B
+
C5
C4
C1
MM IN
C3
C11
C12
C107
C103
+
++
RIGHT
LEFT
MC IN MC IN
C112
C110
C109
C9
C10
C1A
C7
RIGHT
MM IN
LEFT
MC JP MC JP
LEFT RIGHT
12AX7
V101 V1
12AX7
12AX7
V2 V1 and V101
use Sovtek 12AX7
in these locations
V2 use 12AX7 JJ
in these locations
1. Remove the top cover of the TL2.5:
Turn off the TL2.5 preamp and remove the power cord. Use a #2 Phillips screw
driver and remove the 6 screws on the top and 2 screws on each side of the
preamplifier. Keep the screws in a safe place so that you can put the cover back
onto the unit when you have completed the following installation.
Check to make sure that the optional phono PC board is installed to the left of the
line stage PC board in your preamplifier. If you have any questions, please call
your dealer or the VTL factory for assistance.
2. Selecting MM
Jumpers on Phono PC Board: (near MM Input pads) There are two small
black jumpers located on the phono PC board near the left and right MM
Input pads. To set the phono stage for MM, lift the black pin jumper and
connect the jumper to one pin of the header only (does not matter which pin).
Do this for both headers (one per channel).
Tubes on Phono PC board: If you are using the phono board for MM only,
the tube in socket V2 can be removed.
Jumpers on RCA Input PC board: there are two sets of jumpers for
configuring the phono board to MM. Please change the connectors on the
TL2.5 Preamplifier Owner’s Manual
VTL 14
two configuration boxes and put the them across pins 4 and 5 and pins 9 and
10 respectively.
3. Selecting MC
Jumpers on Phono PC board: (near MM Input pads). To set the phono stage
for MC, make sure both pins of the header are connected by the jumper.
Tubes on Phono PC board: (MC) – For MC mode, install the 12AX7A China
tubes to the tube sockets closest to the edge of the board (V2).
Jumpers on RCA Input PC board: there are two sets of jumpers for
configuring the phono board to MC. Please change the connectors on the
two configuration boxes and put the them across pins 3 and 4 and pins 8 and
9 respectively.
4. Replace the cover
Put the cover of the preamplifier back onto the unit, and insert and tighten all
10 screws.
5. Connecting the turntable to the preamplifier
Connect the RCA input cables from the turntable to the Aux2/Phono RCA inputs
of the preamplifier. Loosen the binding post of the ground connection and place
the ground connector(s) from the input cables to the binding post.
6. Power the preamplifier and your amplifiers on and check to see that there
is no hum in the system. There should be a mild rush from both channels
at high volume, with no hum present. If you experience hum or any other
anomaly then please call the VTL factory for clarification.
TL2.5 Preamplifier Owner’s Manual
VTL 15
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