The CORON DS8 (DC861) is identical to the DS7 plus a colored noise generator with bicolor filter and a balance pot to mix the noise generator and the VCO sound before it reach the output VCA.

The Noise generator allow to synthesize analog Hihat or snare drums and other kinds of noisy sounds.

The vintage box is quite similar to the DS7 one with more pots and switches on the top side, and red labels on the panel instead of withe ones for the DS7..

Schematic

Here is the updated wiring diagram for the rev 1.1 board . Clic on the picture to view it full size...

There is now a pad named J102 ( R100) . It is a CV input to modulate the VCO pitch by external voltage sources . An attenuator pot can be added to this input. Notice this CV input is not 1V/Oct but it will work fine with modulations between 0..5V . It is also advised to add an attenuator pot on this input ...

The noise generator is a very classic design with a pair of transistors. It is colored by a switchable 2 colors 1 opamp filter ( hi/lo)...It is simple to replace the switch by a rotative selector and a set caps of different values to get more "colors"...

The DS8 clone (prototype v1.0) at the end of assembly.

 

DS8 Builder's FAQ:

I often receive same questions about the DS8 construction so here are anwsers :

Q) What is R31 value ? What does 'NC' mean ?
A) R31 is marked as 'NC' ... NC mean = Not Connected ... forget this resistor ! Not used...

Q) What is R8 value ?
A) R8 value is 22k like the DS7 .

Q) The output level is low ... What can i do ?
A) The output level is sized to be around -10dBu nominal. To increase it : replace R30 ( 100k) by a 330k or 470k resistor . This should be enough for most of applications, including modular synthesizers patches ... Another solution: use a good preamp...