Advertisement
Bluetooth Operation
(Where fitted)
1. Attach antenna to rear of amplifier unit.
2. To start Bluetooth pairing operation switch the front
selector to "Bluetooth".
3. Now open the Bluetooth menu of
your phone (or other device) and
search for "iconaudio" in the list,
then "pair" with the HP205D.
4. Select and play music as required.
5. From your Bluetooth menu select
"LDAC" for best quality if supported.
6. Note the maximum range may be
limited by walls, furniture and other interference sources.
7. When the HP205D selector switch is changed to
"source" the Bluetooth receiver is switched off, so it will
be necessary to "pair" again before use. In some cases
this will occur automatically.
To give you the best sound quality from your phone or
other Bluetooth devices we have used a sophisticated
receiver which complements the design of the HP205D.
Use maximum volume level on your phone for best signal
to noise ratio.
Under some circumstances you may hear interference
from your phone or paired device is it is too close.
Occasionally strong wi-fi or other interference may be
heard. Switch off other unit or move to another location.
Features:
•
Uses the CSR8675 chip, one of the best available.
•
Bluetooth digital audio signal reception by I2S
digital signal transmission with ES9018 chip
decoding.
•
The analogue audio output is buffered by a Burr
Brown OPA2604AP dual op amp MOS FET chip.
•
Uses LDAC protocol and supports a sampling rate
of 24bit/96kHz, which exceeds the APTX-HD's 24-
bit/48kHz sampling rate.
•
Uses an advanced DC power supply with multi
stage voltage regulator to low noise and high
quality operation. The Bluetooth module, DAC chip,
op amp chip are powered independently. The op
amp uses dual (positive and negative) 13V power
Trouble Shooting
Amplifier Dead
Check the 500 mA (1 amp USA) "T" 20mm mains fuse
which is in the IEC mains socket on the rear of the power
supply. A spare in is in the little drawer. These are
available from Icon Audio should you have any difficulty.
The fuse in the UK mains plug (if fitted) should be a 3 or
5 amp fuse, although unlikely to fail.
If the amplifier is lit up but no sound there is also a
100mA "T" fuse inside the amplifier unit with a spare. If
fuses continue to blow there is fault which need the
attention of an engineer.
No sound
Have you selected the right input? Are the connections
OK? Is everything switched on? Are the headphones
connected? With headphones connected but to input
connection slight noise will be heard at full volume.
Distorted sound.
Try another source; if sound improves then it's probably
something wrong with the first source. If no improvement
try different headphones, if no improvement could be an
amplifier problem.
Hum Adjustment for V1, V2
The 205D DHT (Directly Heated Triode) valve uses the
heater filament for the "Cathode" which means that a
circuit is needed to "balance out" any hum for both left
and right channels. It is unlikely that will ever need
adjusting as it is pre-set in the factory, refer to a
qualified engineer. It will not help with hum problems
external to the HP205D.
Other Hum Problems
If you experience hum that increases with the volume
control this is external to the HP205D this could be
caused by poor grounding or using unscreened RCA
cables or a "ground loop". This may be checked by trial
and error by consulting your dealer. Example: Disconnect
other sources one by one. You could try a different wall
socket.
Other causes of low-level hum can be from adjacent
equipment, so experiment with moving equipment around
to see if this makes the hum better or worse.
One channel missing.
Usually 'bad' connection on either the input or the
headphones. Try swapping the connection over to
establish if the cause is:
(a) Input to the amp.
channel.
(b) Amplifier or headphones. Sound will not move.
Strange noises coming through headphones
Turn volume to minimum, if the noise persists there may
be a problem with amplifier, or external interference from
mobile phone, wi fi etc.
A valve problem may be checked by swapping the valves
over from left to right. A valve that is glowing does not
mean it is working properly; but a valve that is not
glowing cannot function.
Valve life and Replacement
Valve life depends upon such things as hours of use and
number of on/off cycles. As a very rough guide we would
estimate life of approximately 4 to 6 years. But this can
vary massively depending upon usage and the possibility
of sudden failure.
As a rough guide if the amplifier sounds good the valves
are probably fine. Valve can reduce by up to 30% without
any drop in performance.
What can happen?
A valve is at the end of its life or has failed if one of the
following happens:
•
The valves wear out reducing the sound quality
especially at high volume levels.
•
One of the glowing heaters fails, in the 205Ds or
the 6922s (two heaters in each valve).
•
A valve could get "noisy" or excessively
"microphonic" Tap them gently to find out).
205Ds are normally a little microphonic.
•
The emission (and therefore output and sound
quality) may fall giving low output.
•
The valve works intermittently.
•
An air leak causes the valve to fail and the silver
"getter" material to turn white.
Sound will move to the other
Page 4
Advertisement
