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USER MANUAL
First of all may we sincerely thank you for choosing this Unison
Researchaudio component. All our products are made with great
care and pride, and and we hope that your new purchase will give you
many years of satisfaction and musical pleasure.
Please take a little time to read the following notes. They will
help you to get the best from your new Unison ResearchP30K.
Every Unison Researchproduct is the fruit of great
experience in electronic design as well as a profound knowledge of
vacuum tubes and how to get the best performance from them. It is
also the result or our passion for making unique and valuable pieces
of audio equipment in which traditional craftsmanship and advanced
electronics join together in harmony.
All our products are made using fine quality materials and each
one is inspected at various stages of the production process to ensure
that it meets our own very high standards.
All the wood detailing is made by expert craftsmen from prized
solid hardwoods and hand-finished using organic laquers to enhance
the natural beauty of the wood. As well as having visual appeal, the
wood parts serve the more serious function of helping to damp
resonance in the metal chassis, with clear benefits to sound quality.
1. UNPACKING
Please check that the packaging is intact and that the product has
not suffered from rough handling during transport. If you are in any
doubt, we recommend that you contact your Authorised Dealer for
advice before proceeding to instal it.
Note that some accessory parts (in particular the valves) may be
packed separately for safety in transport. Please refer to section 4 for
guidance on correct fitting of these items.

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IMPORTANT !
After unpacking allow time for the product to reach normal
room temperature before connecting up and switching on. This is
to allow any condensation to dissipate, which might otherwise
cause damage to the electronics. Remember also that
condensation can form when moving the amplifier from a cold
place to a warm room.
Keep the packaging in a safe place. Any time you need to
transport the amplifier it will be best packed safely in its original
carton.
2. FITTING THE VALVES &
AMPLIFIER PLACEMENT
Remove the protective valve cage as detailed in para. 4
Insert the valves in their respective sockets, taking care that the
orientation and position of each (V1, V2 etc) is correct.
Refit the protective valve cage.
When choosing the best position for your Unison Research
P30K please bear in mind the following guidelines.
Valves are sensitive to shock and mechanical vibration which in
turn can affect the quality of sound. For this reason avoid placing the
amplifier close to the loudspeakers. Placement on a sturdy and
resonance-free shelf or equipment support will enable the amplifier to
perform at its best. Always remember to allow adequate ventilation
above and around the valves.
3. CONNECTING INPUTS AND
OUTPUTS
IMPORTANT
Ensure that both the preamp and power amp are
switched off before making the following connections !
Using RCA phono interconnects of suitable quality, connect
the outputs from your preamp to the inputs on the rear panel of the
P30K. (Red = Right Channel, Black = Left Channel)

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On the rear panel of the P30K you will find three sets of
outputs to the loudspeakers, marked 4 Ohm, 8 Ohm and 16 Ohm.
These outputs will accept loudspeaker cables terminated in any of the
following ways: spade terminals, bare wire or 4mm plugs.
Connect your loudspeaker cables to the output which is closest to the
nominal impedance value of your loudspeakers. If in doubt, consult
your loudspeaker User Manual or refer to your Authorised Dealer for
advice.
Remember when connecting the loudspeaker cables to
respect the correct phase (red = +/black = -) for each channel.
P30K in Mono Use
The P30K is supplied from the factory for use as a stereo
amplifier. It may however be used as a mono amplifier by making the
following adjustments:
- with the amplifier switched off, move the stereo/mono
switch on the rear panel to the mono position. Unscrew
and remove the red (+) loudspeaker output terminals.
- referring to the printed instructions on the rear panel,
insert the three gold links as indicated.
- Replace and retighten the terminals. Note that this
operation modifies the output impedance and provides
double the power output from the P30K.
- N.B. In mono use you may insert the input from your
preamplifier into either Left o Right input.
The P30K has been designed and built to withstand both
short-circuit and no-load conditions, even for prolonged periods of
time. However, we do not recommend you try this out ! Remember
that it is good practice to ensure that all input and output connections
are securely made and correct when the equipment is in use.
4. REMOVAL OF THE PROTECTIVE
VALVE COVER
The P30K is supplied with a protective cage for the valves. This can
be removed to allow valve fitting and replacement. A hexagonal key
is supplied for this purpose. To remove the cage proceed as follows:
- Insert the hexagonal key into the square holes at each
corner on the top of the valve cage.

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- Locate the four screws holding the valve cage in place,
and unscrew each one by two turns.
- Slide the valve cage to the left until it is free from the
screws and then lift it clear.
- Replacement of the valve cage is the reverse of the
above procedure.
5. CONNECTION TO THE MAINS
Before connecting your P30K to the mains, ensure that your
local mains voltage is the same as that indicated on the rear panel.
Never connect the amplifier to AC mains if the local voltage
is higher than that indicated on the rear panel!
The mains fuses are situated in the fuse-holder which is integral
with the IEC mains socket. The correct value of mains fuses is
indicated on the rear panel and in the technical specifications at the
end of this manual. Always replace fuses with new ones of the same
type and value !
6. OPERATION
Warning! Switch on the P30K only after all the input and
output connections (including loudspeaker connections) have
been made and checked !
Before switching on, ensure that the volume control is at zero
(fully anti-clockise), and allow around 30 seconds from switch-on for
initial warm-up and stabilisation of the valves before turning up the
volume.
Note that good practice for switch-on and switch-off is as
follows: Switch on the Preamplifier first, then the Power Amplifier.
When switching-off, reverse the above sequence.
The P30K takes about 15 minutes from switch-on to reach its
best performance.

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If you need to make adjustments thereafter to the source or the
outputs, always remember to turn the volume down to zero before
doing so.
When switching on the P30K for the first time, we recommend
you check that the sound image is correct by playing a piece of music
that you are familiar with. If there is any doubt it will be best to
double check all the connections before proceeding.
7. SAFETY PRECAUTIONS AND
MAINTENANCE
Never operate the amplifier with either the bottom or top covers
removed.
High voltages are present within the P30K, which could
cause severe electric shock.
Do not operate the P30K unless the protective valve cage is
securely fitted !
Do not open the amplifier !
There are no user adjustments inside, and none other than those
described in this manual.
For technical assistance or product service please refer to your
Authorised Dealer or to a Unison Researchauthorised Service
Centre.
Do not spill liquid into the amplifier !
If liquid should be accidentally spilled into the amplifier remove
the mains plug from the wall socket immediately and seek assistance
from an authorised Sevice Centre before attempting to operate it
again.
Before inserting the mains plug into the wall socket ensure that
the switch on the amplifier is in the “OFF” position.
If you do not intend to use the amplifier for a long period of time
we strongly recommend you unplug from the mains at the wall
socket.
Cleaning the P30K.

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Cleaning should be carried out after switching off and allowing
the amplifier to cool down.
Use a soft dry cloth.
Do not use solvents or alcohol-based detergents.
Do not rub hard on the screen-printed legends on the top cover.
The wood parts are made from natural solid hardwood and will
benefit from occasional cleaning. Do not use anything abrasive, just a
touch of natural wax polish from time to time. This will keep the
lustre and patina of the wood in perfect condition.
Never operate the amplifier when covered! Adequate ventilation
is essential at all times!
Never attempt to remove the valves when the amplifier is
switched on. Always switch off and allow it to cool down.
Valves are shock sensitive, especially when hot. Take care not to
subject the amplifier to shock or vibration.
Replace the valves using others of the same type and quality. If
in doubt, refer to your Authorised Dealer for advice.

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8. TECHNICAL SPECIFICATIONS
Type : valve amplifier, stereo/mono
Mode of operation: pure Class-A
Output stage: single-ended parallel ultralinear
Valves: power output stage 4xKT88,
driver stage 2xECC83
Output power: 30 watt per channel stereo
60 watt per channel mono
Output Impedance: 4-8-16 stereo
2-4-8 mono
Weight: 28 kgs.
Dimensions (w x d x h): 27.5 x 46 x h.20 cm

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DECLARATION OF CONFORMITY
for
P 30 K
Amplifier
Manufacturer
A.R.I.A. Advanced Research In Audio srl
Via E. Barone, 4
31010 Dosson di Casier (TV)
ITALY
Statement of Conformity
Based on test results using appropriate standards, the product is in conformity with
Electromagnetic Compatibility Directive 89/336/EEC
92/31/EEC
93/68/EEC
Low Voltage Directive 73/23/EEC
93/68/EEC
Sample test
Standard used:
EN 55013-1 : 1993 (and subsequent modifications)
Limits and methods of measurement of radio disturbance
characteristics of broadcast receivers and associated
equipment
EN 61000-3-2 : 1995 (and subsequent modifications)
Electromagnetic compatibility. Part3: Limits – Section 2:
Limits for harmonic current emissions (equipment input
current 16A per phase)
EN 61000-3-3 : 1995 (and subsequent modifications)
Electromagnetic compatibility. Part3: Limits – Section 2:
Limitation of voltage fluctations and flicker in low-voltage
supply systems for equipment with rated current 16A
EN 60335; EN 61305-1; EN 61305-3; CEI 84-2; CEI 84-3; CEI 84-8.
The tests have been performed in a typical configuration.
This Conformity is indicated by the symbol , i.e. « Conformité européenne ».

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INDEX :
- Introduction pag. 2
1. Unpacking pag. 2
2. Valve fitting and placing the P30K pag. 3
3. Connecting the inputs and outputs pag. 4
4. Removing the protective valve cage pag. 5
5. Connecting to the mains pag. 5
6. Operation pag. 6
7. Safety precautions and maintenance pag. 6
8. Technical specifications pag. 9
- Declaration of Conformity pag. 10
Unison Researchis the registered trade mark of A.R.I.A. Advanced
Research In Audio S.r.l..