Wright Audio L-5 Instructions Manual

Wright Audio

Stereo Preamplifier Instructions

L- 5

Please take a few moments to read this manual. Doing so will enable you to thoroughly enjoy your
new audio system's quality and fully utilize its versatility. But first some cautions. Most 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 down. However, a faulty part or other conditions
may cause a transient to be passed to a power amplifier or crossover. To avoid
costly damage, get in the habit of turning the preamplifier on first and letting it warm
up for a couple minutes before you turn on your external crossover or power
amplifier.

When shutting down, it is best to turn off the solid-state devices first and the
preamplifier last.

1. Never touch the exposed pins on the Control Unit's back panel when the
power supply interconnecting cable is unplugged from the Control Unit.

2. Connect the unit to an electrical outlet providing 50 to 60 cycles AC and the
voltage marked on the power supply. The unit will operate satisfactorily when
operated within 5% of that shown on the unit. Any other voltage will void the
warranty.

3. 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.

4. The power cord should be unplugged from the AC outlet when the unit will not
be used for an extended period of time.

5. The unit must not be exposed to excessive moisture. Never use any more
than a cloth lightly moistened with water to clean it.

6. The tubes become warm to hot in normal operation.

7. Never switch or disconnect input or output cables while the system is turned
on. Doing so may damage your speakers.

8. Opening the unit voids the warranty.

9. Tubes must be replaced at the end of their useful listening life, which is about
4000 hours, or approximately 4 years of 'average' use. Operation past this
point will not provide quality sound. Wright Audio always supplies the proper
replacement tube types at reasonable prices.

10. Do not open the covers of the control unit or the power supply. Lethal voltages
exist within, even when the power cord is disconnected from the outlet.
Only a qualified service technician familiar with vacuum tube technology must
service your preamplifier. Preferably, it should be returned to Wright Audio if
there is a malfunction.

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11. Always install tubes of the identical numbers as shown on the unit’s rear plate.
Inserting any other tube number may likely damage the preamplifier. Tube
numbers are always marked on the tube. If in doubt of a tube type, contact us.

INSTALLATION AND OPERATING NOTES

1. Position the Preamplifier so that children or pets can not inadvertently touch the tubes.

2. Locate the unit so there is adequate ventilation, with at least 3 inches of space above it.

NOTE: Always make sure the RCA plugs interconnecting the Preamplifier, all other
components and the Power Amplifiers 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.

INPUTS

Insert the appropriate plugs to the Preamplifier's inputs. The inputs are all electrically
similar and are interchangeable.

If you are not using a signal processor such as an equalizer, the Processor/Spare 3 input
becomes the 7th Line input (Spare 3) and is selected by the marked front panel switch.

OUTPUTS

RECORD 1, 2

Connect the inputs of one or two recording devices to these outputs. The front panel
Record switch directs the signal from the input selector to each of the two outputs to
prevent interaction from the record amplifiers and also serves to isolate the outputs from
the rest of the amplification chain. All 3 (Record 1, 2, 3) outputs may be used for a
headphones amplifier with a volume control. When not using these outputs, leave this
switch in the 'Off' position.

RECORD 3 (LINE)

This output is unaffected by the Volume Control, is identical to the RECORD 1 and 2
outputs and is suitable for driving a separate line distribution amplifier or transmitter for
multi-room sound distribution. It also may be used for connecting to a third recording
device. It is activated in the RECORD 3 position. Leave the front panel RECORD switch
in the 'Off' position when not using this output.

HIGH IMPEDANCE / HIGH PASS ROLLOFF

The high pass Rolloff Control on the front panel is active only on this output. It is used for
bi-amplification and is connected to a power amplifier with an input impedance of between
100K and 500K ohms driving the main speaker system.

LOW IMPEDANCE / FULL-RANGE

This output is for connection to a power amplifier for full-range use or an external plate-type
crossover / amplifier / subwoofer system with an input impedance of not less than 25K
ohms.