Valve | Standard LE | Specifications | Valve Standard LE Specifications

Valve Amplification Company
VAC Standard Preamplifier
&
Standard Preamplifier LE
Instructions
Manual issued - 7 April 2004
revised 07/15/2009
Revised 09/09/2009
Please read carefully before installing
Copyright 2004 and 2009 by Valve Amplification Company. All rights reserved.
WELCOME
Congratulations on your purchase of the VAC Standard Preamplifier, and welcome to the
family of VAC owners!
Your VAC is designed not to the latest fad but to substance, providing the highest quality
of sound. Time spent familiarizing yourself with this manual will be well rewarded.
It is our goal to provide instruments of the highest quality, be informative to all of our
customers, and to provide responsive, effective customer service.
Please feel free to contact us if we can be of assistance. We can be reached:
Telephone
Fax
E-mail
Website
941 952 9695
941 952 9691
info@vac-amps.com
www.vac-amps.com
We look forward to being of service, even as you have many years of enjoyment from your
VAC Standard Preamplifier.
Kevin M. Hayes
President, VAC
INTRODUCTION
The VAC Standard Preamplifier is an all new design, employing three Class A triode tube
sections per channel in a direct-coupled two stage circuit. This simple, elegant design
provides great speed, detail, punch, and musicality. Its moderate gain structure and low
output impedance provides an excellent match with a wide range of popular power
amplifiers.
The robust and massive external power supply makes available an extraordinary degree of
headroom, and keeps all e.m.f. fields and rectifier switching noise away from the audio
signal, thus preserving both the power and delicacy of the music.
The chassis is rigid and non-magnetic.
Optional features include triode MM phono stage, triode MC phono stage, and remote
control.
Page 2
GENERAL PRECAUTIONS & SAFETY NOTES
1.
DANGEROUS VOLTAGES EXIST WITHIN THE MAIN CHASSIS. DO NOT
REMOVE CHASSIS COVER UNTIL UNIT HAS BEEN SWITCHED OFF AND
UNPLUGGED FROM THE WALL OUTLET (POWER) AND ALL
COMPONENTS FOR 15 MINUTES. TUBES BECOME HOT IN USE, AND CAN
CAUSE INJURY. DO NOT EXPOSE CHASSIS TO MOISTURE. DO NOT PLUG
INTO AN AC SOURCE UNTIL ALL CONNECTIONS ARE COMPLETED AND
ALL COVERS ARE INSTALLED. DO NOT DISCONNECT THE POWER
SUPPLY FROM THE MAIN CHASSIS UNTIL THE UNIT HAS BEEN
SWITCHED OFF FOR 15 MINUTES.
2.
Complete all signal connections and connection between the power supply and the
main chassis before connecting the AC cord to the wall outlet and turning the unit on.
Similarly, always turn the amplifier off and remove the AC power cord before
detaching cabling. Failure to observe this sequence can result in damage to the
amplifier, speakers or associated components.
3.
At turn on, all volume controls should be full counter-clockwise and the mode switch
should be set to “Mute”. Allow the preamplifier to warm up for one minute before
you unmute the unit; failure to wait can cause a transient to be sent through your
power amplifier that might cause damage to your loudspeakers. Note: Mute is
automatically engaged when switching on units equipped with the remote control
option.
4.
For protection of your speakers and power amplifier, always switch amplifier to
“Mute” before switching the power off or on. Note: Mute is automatically engaged
when switching on units equipped with the remote control option.
5.
THE POWER SUPPLY CONTAINS NO USER SERVICEABLE PARTS. DO NOT
REMOVE THE BOTTOM COVER. LETHAL VOLTAGES ARE PRESENT
WITHIN THE CHASSIS. DO NOT OPERATE THE UNITS IF THEY ARE WET.
6.
THE MAIN CHASSIS CONTAINS VACUUM TUBES. DANGEROUS
VOLTAGES EXIST WITHIN THIS CHASSIS. NEVER REMOVE THE COVER
UNLESS THE UNIT HAS BEEN SWITCHED OFF AND DISCONNECTED FOR
AT LEAST 15 MINUTES. THE TOP COVER MUST ALWAYS BE LEFT
SECURELY IN PLACE.
7.
Take care to install your preamplifier securely in a sturdy, well designed stand so that
it will not fall or tip over (this could cause serious, possibly fatal injury).
Page 3
INSTALLING THE STANDARD PREAMPLIFIER
Physical requirements:
1)
Provide Adequate Ventilation.
2)
The chassis cover will become warm during normal use.
3)
This component must be installed in a secure, properly built (and ventilated) stand,
cabinet or enclosure. It is heavy, and could inflict serious injury or property damage
if it falls, or if the stand upon which it is placed tips over. This concern is particularly
important in households with small children who might try to climb furniture.
Basic Hookup:
1)
Connect line level inputs (CD, Tape, etc.) to the appropriate RCA input jacks on the
rear panel. With the exception of Phono (when fitted), all inputs are “line level”.
2)
Connect phono cables to the rear panel RCA input labeled “Phono.” Connect the
ground wire from the turntable or phono cable to the “Ground” terminal provided on
the rear panel. (See “Phono Section” for cartridge types appropriate for use.)
Connect output interconnects to your power amplifier.
3)
Connect the cable from the power supply to the main chassis. Be sure to insert the
connector properly, and fully tighten the locking collar.
4)
Connect the AC power cord to the IEC connector on the power supply. ALWAYS
connect power cord to component before plugging it into an AC outlet, and make
sure that unit’s power switch is set to “off” before making the final connection. For
best performance, try to route the power cord away from signal cables.
5)
Before turning the power switch to the “on” position, mute the unit by moving the
“Mute” switch to its clockwise (i.e.., muted) position, and set output level to zero by
rotating the “Volume” control fully counterclockwise. Note: Mute is automatically
engaged when switching on units equipped with the remote control option.
6)
Allow the preamplifier to warm up for a minute before you unmute the unit; failure
to wait can cause a transient to be sent through your power amplifier that might cause
damage to your loudspeakers.
As with all high performance audio products, the sonic characteristics of all VAC products
will continue to improve during the first several hundred hours of use.
Page 4
OPERATING THE STANDARD PREAMPLIFIER
Front Panel Controls:
Although most of the front panel controls (Volume, Power, Mute) are self explanatory, VAC
has outfitted this unit with several advanced features which bear further description:
Phono Section MM (option): When fitted, input “L6" will be connected to a discrete, pure
tube phono preamplifier, providing 37 dB of gain, suitable for use with MM (moving
magnet) and many high-output MC (moving coil) cartridges. Your VAC dealer can
recommend the proper phono cartridge(s).
Phono Section MC (option): As above, this will be fitted to “L6", and provides
approximately 60 dB of gain. It should not be used with high output pickups, which may
generate excessive distortion. Your VAC dealers can recommend the proper phono
cartridge(s).
Monitor: The small knob found at the lower left-hand corner of the faceplate switches
between “Source”, “Tape”, and “Cinema” (home theater pass-through mode). In the
“Source” position, input selection is determined by the Source Selector Switch. In the
“Tape” position, the Source Selector is overridden, and the Tape inputs are activated.
[Important: The Standard Preamplifier is outfitted with a full “tape loop”, including a line
level tape input and a fixed level recording output. In addition to driving the recording
inputs of a tape deck, this output can supply signal to any typical line level input, enabling
it to control a second zone in multi room installations.]
The “Cinema” position provides access to one of the Standard Preamplifier’s most unusual
feature. When set in the “Source” position, input choice is governed by the Input Selector
switch. This is the normal setting, and enables the unit to be used as a typical preamplifier.
Rotating the control clockwise to the “Cinema” position bypasses all preamplifier controls
(including volume) and passes the output from your surround sound processor (i.e., the front
left- and right-channel outputs of a multichannel processor) directly to your power amplifier.
In this case, the users’ analog stereo sources would be connected, as usual, to the line, phono
and tape inputs. A/V inputs (DVD, Laserdisc, DSS, etc.) would be connected to the home
theater processor, and the processor’s main outputs would be connected to the pair of rear
panel RCA jacks labeled “Home Theater Direct”. When the control is set to the “Cinema”
position, the Standard functions as a pass-through ONLY, and is controlled by the external
processor, preamplifier, or other component connected to the “Home Theater Direct” inputs.
Mute: On units without remote control, this is a two position switch. In the “Mute” position,
signal is blocked from leaving the preamplifier. Note: Mute is automatically engaged when
switching on units equipped with the remote control option.
Page 5
On units with remote control, this knob is spring loaded; moving the control clockwise will
toggle between the “Mute” and “Operate” condition. When muted, a red glow will be
observed in the LED. On occasion the preamplifier may seem not to have responded to a
turn of the “Mute” knob; this is due to “contact bounce” in the switch. Simply turn the knob
again until the desired condition is attained.
The preamplifier must be muted before power is switched on or off. When switching on,
always allow the preamplifier to warm up for a minute before you unmute the unit; failure
to wait can cause a transient to be sent through your power amplifier that might cause
damage to your loudspeakers.
STANDARD PREAMPLIFIERS WITH REMOTE CONTROL
The optional remote control allows for wireless adjustment of “Mute” and “Volume”.
The remote wand is powered by two “AAA” batteries. These should be of the alkaline type.
You will need to install them in the wand before using the remote. Since batteries can leak,
they should be removed from the wand if it is not going to be used for an extended period
of time.
Volume Up/Down: These buttons cause a motor to turn the volume control. Motorized
controls offer superior sound, as well as direct visual indication of volume setting. The front
panel control may also be used directly in the conventional way.
Mute: Pressing either side of the “Mute” button will toggle between the “Mute” and
“Operate” condition. When muted, a red glow will be observed in the LED indicator. Mute
is automatically engaged when switching on units equipped with the remote control option.
Always mute the preamplifier before switching power off or on. When turning on, allow the
unit to warm up for one minute before unmuting.
OBTAINING THE BEST PERFORMANCE
Precautions: Before removing cover, mute the preamplifier, turn power switch to “off”
position, disconnect the AC power cord from the wall, remove all interconnects, and wait
15 minutes. FOLLOWING THESE STEPS IS IMPORTANT TO PROTECT YOUR
SAFETY. To prevent loss, place cover screws in a small receptacle. To avoid the risk of
shock or other injury, reinstall cover before reconnecting the system or turning the unit on.
Page 6
MAINTENANCE
Chassis Care:
Although your VAC chassis and faceplate are extremely durable, their finish can be
scratched, chipped or damaged if improperly treated. Cleaning with a soft, damp cloth while
the amplifier is switched off and unplugged should restore the finish to its original lustre.
Never clean this component with harsh or caustic cleansing agents.
When shipping your unit, be certain to wrap the amplifier in the cloth, tissue or plastic wrap
in which it was originally packaged. Given the high gloss of the lacquered finish, make sure
there are no ridges or sharp surfaces in those parts of the cloth which contact the faceplate.
Use of a coarser cloth or failure to otherwise protect the faceplate may result in damage to
the finish. VAC is not responsible for cosmetic damage resulting from improper care or
packing.
Installing New Tubes:
Original Equipment Replacement
tubes are available from VAC.
These tubes ensure your Standard
Preamplifier will meet or exceed
all f a c t o r y p e r f o rman ce
specifications.
DANGEROUS VOLTAGES
EXIST
WITH THIS
COMPONENT. YOU MUST
FOLLOW THESE STEPS TO
PROTECT YOUR SAFETY.
Before replacing tubes, all power
must be turned off. Unplug the power cord from the wall, and remove all audio interconnect
cables. Wait 15 minutes before removing the top cover. Install the new tubes fully firmly in
their sockets, taking care to make sure that pin pattern corresponds to holes in tube socket.
Reinstall the top cover before reconnecting the unit.
NEVER INSTALL OR OPERATE THIS UNIT WITHOUT ALL COVERS IN PLACE.
In the event that trouble is encountered, check all signal, speaker and power connections.
If the problem persists, follow all safety precautions stated earlier in this section, and check
that all tubes are correctly seated in their sockets. If possible, try another tube. If the problem
persists, please consult your VAC dealer or contact the factory directly.
Page 7
GENERAL INFORMATION ABOUT TUBES
It is a truth that each brand of tube sounds different in a particular high resolution circuit.
This is because no two manufacturers make a tube type in quite the same way, and the
central tendencies of the performance parameters will differ slightly with each maker. This
sonic variability may at first seem a liability, but further thought will reveal that it is an
advantage. The owner of a tube amplifier can select those tubes which sound like the real
thing in his/her specific system. VAC can recommend the best tubes for your amplifier.
The tube types used in this component should last for 8,000 to 15,000 hours of use (two to
ten years for most users). There are always occasional exceptions, long or short. If you have
to replace a tube before, say, 3,000 hours, just replace the single tube. If you have to replace
a tube at 8,000 hours, replace them all and keep those still functioning well as spares
VAC will be happy to test tubes for concerned customers.
WARRANTY
Your equipment is warranted for a period of thirty (30) days from the date of purchase.
In addition, if the registration form is received by VAC along with a copy of your sales
receipt from an authorized VAC dealer within this thirty days, the warranty will be extended
to two (2) years (tubes excepted).
This warranty applies only to units sold in the United States of America through authorized
VAC dealers and operated within the United States by the original purchaser. It covers
factory service and, within the continental U.S., standard return shipping. For warranty
information outside of the U.S. contact the importer of VAC equipment for your country.
Units sold outside of the U.S. should still be registered with VAC. It is the responsibility
of the customer and/or dealer to ensure suitability of this equipment for any particular
application.
Your questions and comments are always welcome. Contact:
Valve Amplification Company, Inc.
1911 East Avenue North
Sarasota, FL 34234
Telephone 941 952 9695
Facsimile
941 952 9691
E-mail
info@vac-amps.com
Page 8
VAC STANDARD PREAMPLIFIER SPECIFICATIONS (typical)
Type:
Vacuum tube line stage with external power supply and home
theater (direct power amplifier) mode.
Options:
Remote control for volume & mute
Dedicated MM phono input
Dedicated MC phono input
Line stage preamplifier:
Gain:
Maximum input signal:
Main output:
Tape output:
24 dB
Essentially infinite (attenuation precedes line stage)
Inverting (you may reverse speaker connections if you wish to
compensate, or set your d/a converter to phase reversal)
Unity gain from selector, non-inverting
Phono stage preamplifier:
Gain:
Residual noise:
Overload:
Frequency response:
Notes:
37 dB (measured at tape output)
3 mV at output (S/N ratio approx. 69 dB)
117 mV @ 1 kHz = 8 volts RMS output
460 mV @ 10 kHz
RIAA +/- .25 dB
Does not invert absolute phase.
Tube compliment:
Phono option:
2 x 12AX7 low noise (early units); 3 x 12AX7 low noise (later units)
(The phono stage is located on circuit board at left side of chassis)
Line stage:
2 x 12AU7/6189A & 2 x 12AX7 (line stage)
Warranty:
Three years parts and labor, excluding tubes.
Page 9
STANDARD PREAMPLIFIER REGISTRATION FORM
mail to VAC soon as possible.
Name
______________________________________________________________
Address
______________________________________________________________
______________________________________________________________
Telephone
______/______-_____________
E-Mail __________________________
Dealer name ______________________________________________________________
" address
______________________________________________________________
Purchase date ______________________
Salesperson
Serial Number __________________________
______________________________________________________________
How did you first learn of VAC products?
__________________________________________________________________________
What other brands and models did you consider?
__________________________________________________________________________
__________________________________________________________________________
What made you decide on the VAC?
__________________________________________________________________________
__________________________________________________________________________
Please provide any comments on VAC products or your dealer
__________________________________________________________________________
__________________________________________________________________________
What magazines do you read regularly?
________________________________________________________________________
________________________________________________________________________
What are your hobbies?
________________________________________________________________________
What are your favorite types of music?
________________________________________________________________________
________________________________________________________________________
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