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Old 04-13-2019, 04:37 AM
essrand essrand is offline
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Join Date: Feb 2018
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Quote:
Originally Posted by Bones13 View Post
As I understand it (quite possibly incorrectly) the "gain control" is a resistor ladder system placed at the end of the DAC I/V stage. I saw not mention of an active pre-amp on the website, but that might be what the I/V stage provides. Here is their description from the manual (available on the Bricasti site)

Copied and pasted:

On the left and right sides of the rear you will find the analog inputs and outputs. The lower sets of
connectors are the analog outputs, upper the analog inputs. Both channels are independently powered by
their own linear power supply insuring clean double regulated low ripple power and isolation from any
digital noise from the digital supply.

There are 2 PCBs in each analog section of the M12, layered on top of the other. The top one provides the
analog inputs, pure analog DSD conversion and the R2R ladder resistor level control yielding a pure analog
path when using the M12 as an analog line stage, the signal then passes to the output buffer and connectors
on the lower board. There are 2 inputs, one balanced and one unbalanced and are selected from the front
panel input control.

The lower board contains the PCM dac, clocking and analog output buffers. Each channelís digital section
has its own Analog Devices 1955 DAC used for PCM conversion, it is coupled with a dedicated DDS
clocking circuit located millimeters away from the DAC, assuring extremely low jitter and minimal trace
length for the clock signal and precise clock synchronization of the left and right boards is handled by the
Sharc DSP on the main digital processing board.

The next stage after conversion is the current to voltage stage which creates the analog wave form, and this
is followed by an analog filter section. This is a fully differential analog design with fast high slew rate
analog operational amps.
At this hi gain stage is where the R2R resistor ladder for level control is inserted
for the analog gain control. This is followed by discreet 2 transistor designed output buffer sections,
balanced and unbalanced, each separately buffered and isolated. The balanced output level will reach a
maximum of +16.5 dbm and the unbalanced of 8dbm with the front panel controlled analog attenuator set
at full scale of +8 dB.

I hope that helps. I do love mine
Thanks for the detailed reply.

I bought one last week. It should get to me in a week or so, will let you know how it works out !
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