Wright Audio LT - 6P User manual

Wright Audio
LT - 6P
Stereo Preamplifier Instructions
Please take a few moments to read this manual. Doing so will enable you to thoroughly enjoy your
new preamplifier's quality and fully utilize its versatility. But first some cautions. ost are common
sense, but are here as reminders. These cautions apply to most tube and solid-state amplifiers, and
are not specific only to this product.
PLEASE NOTE: This preamplifier has been designed NOT to produce signal transients
during start-up or shut do n. Ho ever, a faulty part or other conditions may cause a
transient to be passed to a solid-state po er amplifier. To avoid costly damage, get in
the habit of turning the preamplifier on first and letting it arm up for a minute before
you turn on your solid-state po er amplifier.
When shutting do n, it is best to turn off the po er amplifier before the preamplifier.
1. Connect the unit to an electrical outlet providing 50 to 60 cycles AC and the voltage
marked on the back panel. The unit will operate satisfactorily when operated within
5% of that shown on the unit. Any other voltage will void the warranty.
2. These units have been supplied with a 3-prong grounding plug. This arrangement
is utilized as an added measure of safety. Do not defeat its purpose in any way.
3. The power cord should be unplugged from the AC outlet when the unit will not be
used for an extended period of time.
4. The unit must not be exposed to excessive moisture.
5. The tubes, particularly the 5AR4, become arm to hot in normal operation.
6. Never switch or disconnect input or output cables while the system is turned on.
Doing so may damage your speakers.
7. Opening the unit voids the warranty.
8. Tubes must be replaced at the end of their useful listening life, which is about
4000 hours, or approximately 5 years of 'average' use. Operation past this point
will likely not provide quality sound. Wright Audio always supplies the proper
replacement tube types at reasonable prices.
9. Do not open the cover. Lethal voltages exist within, even hen the po er cord is
disconnected from the outlet. Preferably, it should be returned to Wright Audio if
there is a malfunction.
10. Always install tubes of the identical numbers as shown on the unit’s bottom plate.
Inserting any other tube number may likely damage the tube and possibly the
preamplifier. Tube numbers are always marked on the tube. If in doubt of a
suitable tube type to use, please contact us.

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TUBE SHIELD INSTALLATION AND UNIT PLACEMENT
The tube shields have been provided for partial protection from children and pets as well as
accidental damage.
ake sure the unit is unplugged.
1.) Install the tubes in their sockets. The unit may be supplied with notations as to which
exact tube to go in which sockets for matching purposes.
Take care to align the gap in the pins on the small tubes hich indicates the correct
alignment before inserting. Be sure to press the tubes gently but firmly all the ay
do n into the tube sockets. Do not rock the tubes back and forth excessively as that
may break them.
The large, octal-based tube has a raised 'key' in its center post to indicate the
alignment.
2.) Position the preamplifier with its back facing you, center and install the shields in the slots
starting from the front of the preamplifier and moving in succession towards the back. A small
slotted screwdriver may be used, but only tighten to less than 'finger tight'. The screws do not
need to be tight, only snug to hold securely. Use a small coin such as a dime to secure the
screws for the 5AR4 shield.
3.) Locate the unit so there is adequate ventilation, with at least 2 inches of space above it.
INPUTS
Insert the appropriate plugs to the preamplifier's inputs. The inputs are all electrically similar
and are interchangeable.
NOTE: Always make sure the RCA plugs interconnecting the preamplifier, all other
components and the power amplifier are always fully inserted into the jacks with the outer skirt
of the RCA plug tight around the socket. It may be necessary to very slightly squeeze this
ground connection with your fingers or pliers to ensure a tight fit to the socket. This is
important to check even with new cables as manufacturer's tolerances vary.
OUTPUTS
FIXED LEVEL OUTPUTS 1, 2
Connect the inputs of one or two recording devices, a headphone amplifier with volume
control, audio-video 'pass-through' or any other suitable device not requiring a volume control
to these outputs.
The front panel Fixed Level Output switch directs the signal from the input selector to each of
the two outputs to prevent interaction from the external devices and also serves to isolate the
outputs from the rest of the amplification chain. When not using these outputs, leave this
switch in the 'Off' position. The preamplifier does not need to be powered on to activate these
outputs since they are completely passive.

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MAIN OUTPUTS
Each of these outputs is electrically identical and can be used interchangeably, but are
electrically isolated from each other. This makes them suitable for connecting both a main
power amplifier and a crossover / subwoofer system. Each output can drive up to about 50
feet of low-capacitance cable. Cable recommendations can be provided by Wright Audio.
CHANNEL VOLUME PRESETS, BASS AND TREBLE CONTROLS
The small controls beneath the Volume Control adjust the individual Left and Right Channel
levels. Normally, they are kept as high as possible (preferably always fully clockwise) where
they are nearly out of the signal path. Reducing the level of one channel or the other will
adjust the volume balance between the channels, and turning both counterclockwise will
adjust for higher-output source devices, higher-gain power amplifiers and / or very highly
efficient speakers.
For best sonics, the Bass and Treble controls operate passively and somewhat differently than
other types. When the controls are set exactly at midpoint, they are in the flat or neutral
position. To achieve that, when turning the knobs fully counterclockwise and fully clockwise,
the travel distance between those two points will be slightly unequal.
GENERAL OPERATING NOTES
Like most other components, your unit will require 2 or 3 days of operation about 2 hours per
day before it begins to sound its best. Also, if the system has been stored or inoperative for a
long time, or if you change interconnecting cables or other components, these situations will
require at least 2 or 3 days of 'break-in' time for the entire system to sound its best. This is
true for any high-performance audio system.
Operate your LT - 6P Preamplifier only when you are actively listening to it. Unlike solid-state
equipment, Wright Audio equipment reaches its optimum listening quality in about 15 minutes,
and it is simply a waste of power and tube life to leave it on any longer than necessary.
TROUBLESHOOTING
FUSE FAILURE
If the fuse fails, never replace it with a higher rating or other than a 'SLO-BLO' type. If the fuse
fails more than once consecutively, the 5AR4 tube should be replaced. If the fuse fails again
after the replacement, the unit should be returned to Wright Audio for servicing.
NOISE
Noise can originate from any electrical component in the system or in the quality of the
household AC po er. Be sure you have eliminated all other possible sources of noise
by substitution or isolation of the components and cables before contacting Wright
Audio.

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Any noise or hum caused by the preamplifier during the life of the unit will normally be traced
to dirty or otherwise poor connections at the input / output jacks, faulty cables, defective tubes,
poor tube pin-to-socket connection or worn controls and switches.
For poor RCA cable connections, the best remedy is to apply isopropyl alcohol to a cotton or
preferably a foam swab which can be used to clean the connection.
Liberal application of cleaner to the tube pins which are then inserted in the tube sockets
usually cures any noise originating at this source. Do not use spray-type contact cleaners
on the tube sockets or around the interconnect cable connections as this may damage
the finish or parts.
The application may need to be repeated for successful results.
TUBE REPLACEMENT
Replace the tubes only ith the numbers as sho n on the bottom of the preamplifier.
There are no tube type number substitutions. Al ays be sure the unit's po er has been
turned off and ait for the tubes to cool.
IN CASE OF A PROBLEM OR QUESTION
Your product was designed for at least a lifetime of operation with ordinary common sense
care, occasional tube replacement and relatively minor service. Please accord it with the
same care as you would a fine camera. However, damage can occur during shipping or in
storage conditions where mechanical shock and extremes of temperature or humidity can
render the unit faulty. Neither of these exposures may be visible to the eye.
Your continued satisfaction with our products is extremely important to us. We will be happy to
answer your questions pertinent to the installation and operation of your unit. Please feel free
to contact us in the event of any difficulty and we will endeavor to provide prompt service. If
the problem cannot be resolved through our combined efforts, we may wish to authorize the
return of your unit to us.
In the event the unit must be returned, an authorization number will be forwarded to you. This
number must be placed on the outside of the return box to identify it and avoid unnecessary
delay. Under no circumstances should your unit be shipped to Wright Audio without
authorization or it will be refused. Please pack it carefully in the original packing, if available.
If not, allow at least 3 inches of space all around between the product and the box.
All products should be double-boxed for shipping safely.
Ship prepaid via UPS or Fed Ex only. Be sure to insure the shipment for the full original cost.
Collect shipments will not be accepted.
WRIGHT AUDIO
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