I've been thinking a bit on how to do things like these in as "clean" was as possible. By "things like these" I mean DSD ADC interfacing, for example, but changing channels on the fly is virtually the same.The USB Multichannel feature can be added quite soon after initial release - the DSP EQ software will take longer to implement.
The only "clean" solution known to me is to make DSD a preference possibility and indicate (on the display) whether the recorded PCM data are DSD or real PCM. If some application opens the MDAC2 for 44.1KHz where it has been "set" to DSD, it would fall back to normal PCM.
Multiple channels may be a problem if the device has already announced only 2ch, but I guess you (or Dominik) could make it so that MDAC2 chaining will be detected on device initialization (power on or USB re-plug), ... multichannel "hot plug" might not be very useful.
Ok John, level with us-
a)have ever had the urge deep down to design an entirely proprietary digital crossover active speaker system?
b) do there exist enough bulk foil resistors *in the world* for a 7.2 m-dac crossover system employing 7 3-way speakers (23 channels)
2nd, 3rd & 4th MDAC2's L2 / L3 for multichannel systems can be offered at GBP300 each + PCB "at cost" (so long as the offer is not abused)
Is there any reason for the slaves to be L3 instead of L2, besides standalone use?
How many inputs are left with 3 slave dacs?
Only for those who require 8 ADC inputs (multi-track studio recording), otherwise the L2 and L3 are identical. So must systems would be L3 for the Master unit (for a pair of ADC inputs) and L2's for the expanded audio channels.
With the current rear panel arrangement with all 3 BNC's dedicated to Digital outputs, 3 Optical inputs remain (and USB), but note SPDIF can only support 2 audio channels (this is not relevant to Active speaker set-ups where the expand channels are just EQ'ed for each driver as you are still processing a "Stereo" input).
John
It's very interesting to read all this technical stuff although most of it is way over my head. Like everyone here I'm really looking forward to the improvements you'll make to an already fantastic DAC.
Can you please confirm that L2 will include ClockLock? The last table of MDAC2 options showed "Wordclock & Video Clock Synchronisation" on L3 only, or is this something else? I don't need ADC but would like the opportunity to clock lock if I had a suitable transport or player. Is optical the best way to do this, as it does limit the transports we could use?
Thanks
Martin
I just had a quick try and it sounded the same.
Can you please confirm that L2 will include ClockLock? The last table of MDAC2 options showed "Wordclock & Video Clock Synchronisation" on L3 only, or is this something else? I don't need ADC but would like the opportunity to clock lock if I had a suitable transport or player.
Is optical the best way to do this, as it does limit the transports we could use?
Quite recently someone had an issue with A0.10 - No sound with USB upon bootup, or some such... sadly I've got my head so buried in the MDAC2 design everything else is rather a blur...
Yes, that was me. I don't regard that as a stability issue, though. Just a bug - for which there was a work-around. A.10 is perfectly useable.
- Richard.
"+1" for multi-purpose BNC connectors, a neat idea if it can be done (ie. via multiplexers).Making the BNC connectors "Definable" to allow multi channel expansion is just one example of this "natural" progression
On the MDAC it defaults to 0dB when I plug my headphones into my Little Dot Headphone Amp. Is there any benefit or point in lowering the dB on the MDAC and raising the volume on the amp, or vice versa, does it affect the sound quality or add to your listening pleasure.
I just had a quick try and it sounded the same. Just wondering.
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....I like to stress that just as with the Analogue PCB, the final Spec. of the digital PCB is in a state of "Flux" until I actually complete the design - the design just flows with my ideas as I work on the PCB. .....)