12 Silicon chip Australia’s electronics magazine siliconchip.com.au
on how to hook up the digital audio
output of a television which carries
Dolby Digital/DTS digitally encoded
surround sound signals to the input of
a standard amplifier, such as the one
I built based on your SC200 modules.
You pointed me to an item
on eBay (www.ebay.com.au/
itm//263547481266) which I then
purchased and hooked up to my now
finished amplifier.
I was astounded by the improved
sound quality with the new decoder,
compared to the low-cost stereo com-
mercial DAC I had been using previ-
ously.
Although I am only using it in ste-
reo mode at the moment, the effect was
not just to improve the frequency re-
sponse: I now notice much greater spa-
tial detail in the sound, perhaps best
described as an overall real increase
in natural sound reality.
The bass is better defined and has
a greater impact, especially notable
with very low-frequency sound ef-
fects. These comments apply to all
sound sources, whether HDMI or opti-
cal digital. I have not tried to compare
the Dolby decoder on the DVD player
against the new unit.
I think this would be a fantastic
unit to build into the Tiny Tim am-
plifier described in the October & De-
cember 2013 and January 2014 issues
(siliconchip.com.au/Series/131). It
should give excellent sound quality, as
well as the ability to handle surround
sound encoding.Avoiding leaking batteries
Regarding the question “Why do
batteries leak more in modern equip-
ment?” asked by R. B. in the February
2019 issue, I have also had trouble in
the past few years with equipment be-
ing damaged by leaking alkaline cells.
Because electronic devices can be
very costly and are easily destroyed by
leaking cells, I do not buy bulk packs of
cells any more. I think that these may
contain cells which have been sitting
around for longer and so are closer to
the end of their shelf life compared to
those in the smaller packs.
My suggestions are: only use cells
from reputable manufacturers; meas-
ure battery current flow in devices
which are switched off to ensure there
is no ‘phantom load’; if possible, re-
move the cells from devices when they
are not in use; and use Vaseline on a
cotton bud to coat the springs and endcontact plates, to try to minimise dam-
age if a cell does leak.
Anthony W. S. Farrell,
Kingscliff, NSW.Praise for Silicon chip DAC design
Being of advancing age, I spend a
lot of time listening to my consider-
able collection of CDs (both old and
newer). I also watch a few DVDs of
the music variety.
Recently I felt the urge to avail my-
self of the newer Blu-ray technology, so
I took myself off to our local electron-
ics store. Imagine my dismay when I
discovered that out of the ten or fifteen
players on display, not one had analog
stereo outputs.
They all had only digital coaxial
and/or TOSLINK sockets. I bought
one anyway, paying about $170, and
ordered a relatively cheap digital-to-
analog converter on eBay. The result-
ant sound was a little less than encour-
aging, due at least in part, to the fact
that it operated from a single 5V DC
supply. I believe it was let down by the
analog stages following the DAC chip.
Enter the Silicon chip Stereo Digi-
tal Converter (September-November
2009; siliconchip.com.au/Series/4).
I managed to buy one of the last kits
from Altronics. I understand that once
they have sold out of the current stock,
they will be discontinued. The kit
was straight forward to assemble and
thankfully worked first time (phew!).
I can only say that the definition
and dynamic range this converter pro-
vides is outstanding. It has opened up
a whole new dimension that I have not
heard before from my CDs, even com-
pared to players with analog outputs
I have owned in the past. My hearing
is quite good for my age, having been
told recently by an audiologist that I
have the hearing of a 30-year-old – well
under half my actual age!
One other problem with the current
crop of players under several hundred
dollars is that they don’t have a front
panel display, or if they do, there is
no track number displayed, only the
elapsed time for each track. One has to
turn the TV on to get that information,
which kind of defeats the purpose if
you only want to listen to music.
You need a dedicated CD player
or a Blu-ray player costing upwards
of $1,000 plus to get those features,
which were standard on pretty much
all CD players just a few years ago.
For the record, the rest of my music