Welcome to the Going Stereo page of the Colour Classic Compendium
Colour Classic Compendium
Presented by Stuart Bell (stuartsmacs at dsl dot pipex dot com)
'Going Stereo' - giving your CC stereo sound capability
(Note, of course, that the standard CC logic board will only produce mono sound. You'll need to install the logic board from an LC520 or better to be able to make use of Alexey's findings.)
The above pictures show the twin speakers installed in Alexey's CC.
Alexey Danilchenko describes what's involved:
The Color Classsic analogue board was designed to handle stereo by providing two identical amplifier circuitries - one for each stereo channel. But by default only one for the left channel is used and the signal for the right channel added to the left before going into the amplifier.
The list of what is needed for modification:
(1) amplifier TDA7052A - from Philips (the same as IS2 on analog board)
(2) electrolytic capacitor equivalent to CS4 on analog board
(3) capacitor equivalent to CS2 on analog board
(4) capacitor equivalent to CS6 on analog board
(5) resistor equivalent to RS4 on analog board
(6) speaker connector (probably from spare analog board)
The other possibility is to cannibalise spare analog board for all those components. That's exactly what I've did - that's why I can't detail exact capacitor and resistor values.
The place for the second channel is just next to the first one - both ICs are close to the analogue board connector.
Modification (please note that everything should be soldered by low-power soldering iron to prevent overheating of the board and components):
step 1) solder the amplifier to the place denoted as IS1 (on the face of analog board) - make sure that all IC connectors placed correctly and isolated from each other;
step 2) solder the electrolytic capacitor (2) to the place denoted as CS3 (on the face of analogue board) - make sure that polarity is correct;
step 3) find and unsolder RS7 (back side of analog board - very close to analogue board connector);
step 4) solder just unsoldered RS7 to the place denoted RS2 (on the back side of analogue board - close to the IC soldered on the first step);
step 5) solder capacitor (3) to the place marked CS1 (on the back side of analogue board - close to the IC soldered on the first step);
step 6) solder capacitor (4) to the place marked CS5 (on the back side of analog board - close to the IC soldered on the first step);
step 7) solder resistor (5) to the place marked RS1 (on the back side of analogue board - close to the IC soldered on the first step);
step 8) drill two small wholes in the place marked as SS1 on the face of analogue board - the holes should have the similar layout to the already existing wholes at the place denoted SS2 (that's where existing speaker connector already attached)
step 9) solder (6) at the holes just made similarly to the existing speaker connector (be careful with polarity - should be the same as existing one)
step 10) connect speakers and test - the previously existing connector will be your left channel and newly added - right channel.
Thanks to Alexey for some brilliant photos to illustrate his work. Those below show the details of the circuit board work required. To follow them, extract each image and use a graphics program to display them at their original size - when all will become clear!