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DCX2496 DAC volume control PCB

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bdipoala

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Joined 2004
#1
I have a few PCB's left over from a board run. The boards provide a 100 step digital volume control function for the DCX2496. The level can be adjusted using any universal IR remote control that supports Sony codes. Adjustments can also be made with a digital rotary control. All 6 channels of the DCX balanced outputs are adjusted simultaneously. The board has a few extra level controls for a sub woofer or whatever.

The board provides a 0 to 1.00V output to drive a digital panel meter to indicate the volume level.

The board also can provide an optical digital input that replaces the electrical type on the A input.

If you are not happy with behringer’s op-amp board, I have made a couple of replacement boards that are simpler single stage / signal channel. One board has balanced outputs using new XLR connectors and the other is unbalanced with consumer levels and RCA connectors. See attached picture with balanced outputs

The boards could also easily be used for any DAC project using an eval board or you own design.

I am asking $90 for the bare volume control PCB and $30 for the op-amp PCBs’.

If you would like me to send you better pictures, email me at bdipoala@aol.com
 

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#3
I have been getting alot of questions on my vcontrol PCBs so I am posting the below description to help answer most of the questions. see attached.

I will contine to buy additional batches of PCB's as long as there is a demand for them.
 

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#10
I need three sets. That's a positive on that. ie, soonest.

Let me know soonest. Well..at least one set, for now. Need the output borad as well, which is why I say 'sets'.

And while I'm asking for the world, what in the world made you use digital pots? Are thes digitally controlled VCA's, or are they actual digital VCA's? Digital is yuck, which is the entire 'why' of upgrading a DCX to improve fidelity.

If they are digital VCA's, do you think it would take much to go to an analog unit? Too many d/a a/d d/a thingies going on in there for my taste. The one cycle of the behringer itself is bad enough. The result might be mud. :xeye:

dang. now I have to buy Jan's board too. maybe scratch the output board and I'll buy Jan's unit, now that I remember it exists. Tthe behringer is now available again (which is why I'm even bothering), so I'm back on target again, due to behiringer's complete screw up that lasted nearly two years. idiots.
 
#12
Here's a circuit description from an earlier post from Bdipoala; The Vcontrol PCB provides a means to adjust the output levels of the DCX2496. The Vcontrol PCB can be placed inside the DCX chassis. All connections are made with the DCX's ribbon cable assemblies. No need to cut traces or modify anything on the DCX PCBs'. Electrically, the control circuit is connected between the DAC ( DSP PCB) and the op-amp output circuit (analog IO section PCB) of the DCX. The output level is controlled using 100 step digital potentiometers. The digital pots are effectively passive devices with little to no impact on the signal quality. 12 digital pots are ganged so that all the channels are changed simultaneously. The pots are AC coupled by using 10uF AL capacitors; there is provision for bypassing the AL caps with .1uF polypropylene capacitors for lower distortion, higher performance. Alternatively, high performance caps like Black Gate's may be used (smoke them if you've got them, they have been discontinued). The pots have a linier taper, which is not ideal, but in use this is not very noticeable. The key thing is that the level can be adjusted to the desired point without sacrificing sound quality. Something Behringer did not provide. Hope this helps
 
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