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QUICK SET UP GUIDE
1 Unpack unit carefully
. Make sure that it is in good
condition. It is important you keep the custom packaging
for any warranty/service as this provides maximum
protection.
2 Fit the valves if necessary.
Or if fitted check that they are seated properly. (see also
valve replacement). The smaller 6922 valves should be
firmly pushed into place.
Handle the 205D (or 300B) valves carefully. They have
four pins, two are slightly larger, please observe this
when fitting. All four valves are marked with the socket
they should be inserted into.
The single rectifier valve (274B/GZ34/5AR4) should be
fitted into the power supply. Please note orientation!
Connect the multipin plug to the power supply unit.
Connect the power supply to your wall socket.
3 Connect the HP205D to your source unit
(e.g. CD
player) or from the “Record Out” of your amplifier.
“Loop Out” Facility
This enables you to connect the HP
205D between a pre-amplifier and power amplifier for
example, or it may be used as
a “record out”. Using the
“Loop” facility does not require the HP 205D to be
switched on.
For best results use a screened RCA-RCA cable to avoid
noise pick up.
3.1 For Bluetooth connection see next page.
4 Connect to mains
supply using the attached mains
lead to wall supply.
Outside the UK you may need to
change plug or cable, the welded plug must be
removed and replaced with a suitable type.
Please then
remove fuse and dispose of carefully away from children.
The
replacement plug should be wired in the following way Brown to Live
terminal, Blue to Neutral terminal and Green/Yellow to Earth terminal.
5 Connect your headphones and SWITCH ON!
The power LED indicator should light up and unit will take
approximately 40 seconds to start working. All valves
should have a visible orange glow from the cathode
heaters.
With the volume control set to minimum (fully
anti-clockwise) there should be no sound coming from
your headphones except a barely discernible hum.
5a, Headphone Impedance
The right hand knob marked
L M and H
refer to the
matching impedance of your headphones and are
banded as follows:
Low
8-200 Ohms
(ideally 70 centred on 40-125)
Med
60-600 Ohms (ideally 200 centred on 125-400)
High
250-2000
(ideally 600 centred on 400-950)
The
“centred on” figures will give the best matching
impedance, highest power and lowest distortion. The
HP205D is designed for high quality headphones which
are generally higher impedance and less efficient. Low
impedance
high
efficiency
headphones
are
not
recommended.
6 Your unit should now be functioning
. If not check
you have selected either
“INPUT” or “BLUETOOTH” (if
fitted), the volume is not set to zero and that you have a
an input signal. The best sound quality will be when the
unit has warmed up for about 10 minutes.
7 Health and Safety
. The valves when operating have
moderately high surface temperatures. Keep out of reach
of children and pets.
Under no circumstances operate with valves
removed!
Like all valve amplifiers there are potentially lethal
voltages inside (300v DC), which when switched off
can take up to 15 mins to discharge!
Do not remove
bottom panel unless you are a competent engineer.
There are no user serviceable parts inside. Like other
household electrical appliances do not leave unattended
whilst switched on.
Allow for ventilation!
Do not cover the unit!
Do not allow to get wet!
Do not operate if there is possibility of lightning outside.
It is essential to install the HP 205D on a stable non
slippery surface when it cannot be easily be moved by
accidental pulling of the headphone cable.
Connecting inputs & outputs
Many problems with hi fi equipment involve connecting
leads which are usually either
‘Bad, or Wrong
co
nnection’
. So it’s worth making sure that you have
good connections and that your leads are the right way
round. Use a well screened RCA cable.
Inputs
The amplifier will work with any standard piece of hi fi
e.g. CD, Tuner, Tape Deck, Mini Disc, TV, Video
Recorder, DVD etc.
General points
•
Leave some gap between the power supply and
HP205D to minimise noise.
•
Some m
obile phone ‘breakthrough’ is normal.
•
Some initial noise will be heard until the valves are
fully warmed up.
•
Do not store in damp conditions this could damage
to transformers and other components.
•
300B valves are more microphonic.
Headphone types
The HP205D is designed to work with almost any
conventional moving coil headphones. We use Beyer
Dynamic, Audio Technica and Sennheiser for testing.
Generally high impendence (100
Ω plus) headphones will
sound better. High efficiency types will reveal more noise.
Connecting Leads
Use good quality connecting leads, which are no longer
than they need to be.
Leaving the amp switched on
Whilst the amplifier will sound at its best when it is
properly warmed up after about 5 minutes, there is no
advantage leaving it switched on when it is not in use. It
is using electricity and using up valve life. Conversely the
valves and other components are stressed more at
switch on; therefore do not switch on and off
unnecessarily.
Although the amplifier should sound
good within a few minutes, like most hi fi units it will
take a couple of months of regular use before it is
fully
‘run in’.
Cabinet Care
To remove dust from the cabinet and valves we suggest
gentle brushing with a soft paintbrush and a duster.
Finger marks can usually be removed with a damp cloth.
Always clean with the power disconnected.
