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N_Cook N_Cook is offline
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Default Studiomaster powerhouse vision 12

On 12/12/2016 12:37, Nightlight wrote:
Hi,

I received this desk in bits, literally, in a huge bag and have slowly been
rebuilding it.
There were a number of different revision boards probably from other
studiomaster desks in the bag also.

The modules I,ve used in the desk are as follows

Control/graphics R1A8 - 2

Power amps R1A5 - 4

Aux board R1A9 - 1

PSU R1A1 - 4

Insert pcb R1A3 - 4


The problem I have is no sound from the power amps.

I have traced the l&r signals from the "Amp" volume control on the Aux
board
to CONN 2 (14W) pins 9 and 10 which then goes
via ribbon cable to the control/graphics board CONN 6 pins 9&10 labeled as
*AMP-L* and *AMP-R*.

According to the many studiomaster schematics I managed to find the signal
then leaves the control/gfx board via CONN 2
a 14 WAY to the insert board and PSU board for splitting to the power amps.

Thing is, CONN 2 on the c/g board is 16 WAY, it has to be as the
connectors on
the insert board and psu are also 16 WAY and here lies the problem.

The power amps are expecting the I/P on their CONN 1's pins 9&10 ( IN-
, IN+
) Not AMP-L ( or AMP-R )!!!

I was thinking the c/g board was the wrong revision. The only schematics I
have for the C/G board are for R8C8B-3.

Any ideas folks?

thank you,

Night...


____


What makes you think there is the making of 1 full amp, in that collection?