Unison Research C5P User manual

HIGH - END ELECTRONICS
BORN IN ITALY
C5P

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USER MANUAL
First of all may we sincerely thank you for choosing this Unison
Researchaudio 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 ResearchC5P.
Every Unison Researchproduct 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.

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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.
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
C5P 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 THE INPUTS AND
OUTPUTS

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On the rear of the amplifier you will find the sockets for
connecting the inputs and outputs.
IMPORTANT !
Ensure that both the preamp and power amp are switched
off before connecting up sources and outputs.
The phono input has an impedance selector to enable close
matching with various types of cartridge. Adjustment of the
impedance is carried out by means of the micro-switch placed on the
rear panel at the left corner of the C5P. The earth (ground) wire from
the turntable should be connected to the gold-plated terminal post
marked GND.
4. REMOVAL OF THE PROTECTIVE
VALVE COVER
The C5P 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.
- 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 C5P to the mains, ensure that your local
mains voltage is the same as that indicated on the rear panel.

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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 C5P 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.
The C5P takes about 15 minutes from switch-on to reach its best
performance.
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 C5P 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.

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High voltages are present within the C5P, which could cause
severe electric shock.
Do not operate the C5P 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 Researchauthorised 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.
In 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.
Valve replacement.
Replacement of the three line-level valves is carried out after
removal of the protective valve cage as described in Section 4.
For replacement of the phono valves proceed as follows:
- Remove the stainless-steel reflector plate beneath the
line level valves.
- Remove the screw securing the amplifier top cover
- Remove the top cover by moving it forwards.
Cleaning the C5P.
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.

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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 line & phono preamplifier
Mode of Operation: Pure Class A
Max output level: 20V
Input impedance: 50Kohm//47pF (line level)
Output impedance: ~800 Ohm
Distorsion: THD+noise at1 VRMS out: <0.1%
Output phase: non inverting
Gain: 21.5 dB
Bandwidth: 5Hz-100KHz 1 dB
Inputs: phono-CD-AV-tuner-rec
Outputs: 1 x power amplifier
1 x tape
Power consumption: 40 W
Valves (line): 3 x ECC83 (12AX7)
Valves (phono): 3 x ECC83 (12AX7)
Gain (phono): 52 dB approx
RIAA: passive, 0.2 dB (20Hz to
20KHz)
Impedance (phono input): 47K–100-50-22/
100 pF
Weight: 10 kgs.
Dimensions (wxdxh): 27.5 x 48 x h.20 cm

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DECLARATION OF CONFORMITY
for
C 5 P
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 C5P pag. 3
3. Connecting the inputs and outputs pag. 4
4. Removing the protective valve cage pag. 4
5. Connecting to the mains pag. 5
6. Operation pag. 5
7. Safety precautions and maintenance pag. 6
8. Technical specifications pag. 8
-Declaration of Conformity pag. 9
Unison Researchis the registered trade mark of A.R.I.A. Advanced
Research In Audio S.r.l..