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Whoever follows the Pacific Microsonics  threads, or whoever use Pacific know that both Models one and two have an interesting idiosyncrasy: at maximum sampling rate, when Pacific runs in dual-wire mode, the clock runs at half speed. It does not make since to have A/D running at 176K but clock at 88K. So, it would be responsible to ask: what is the purpose to slave DAW if the processor does not care the right sampling reference?

I was under this presumption for a couple year but last might I suddenly come to me and I concluders that it does not matter. Let me to explain my rational. Be advised that I have no specific knowledge in the field or consulted with knowledgeable people, this is just my take that is based strictly upon common sense, at least the way how I understand the common sense.

There are two arguments that I would like to bring up:

1)  Pacific Microsonics was designed and built by very knowledgeable people who very much knew what they did. Furthermore Pacific was made in “no expense spare mode”, so it is not such a thing the some functionality was not implemented because they wanted to keep it cheaper. So, if Pacific teal decided to output a half-speed clock at in double-wire mode then they feel that it was how it needs to be done.

2)  What is double-wire mode? It is what one wire cares a half sampling rate and another wire cares another half. The double-wire is not stereo and not dual mono.  In stereo we have two different signals that fluctuate by own rules cared in two wire. In dual-wire AES/EBU each wire cares a half of the very same signal and a half of sampling frequency. In dual-wire digital both wires are running from the very same clock and if the signal in dual-wire divided not identically (I do not know if it is possible) then the fluctuation clock marks across the wires are absolutely identically as there is just one clock for both wires. So, what is the clock slaving? It is some king PLL driven phase-locking of one clock to another clock.  The key in here is to get reference and to trace the rate of change. Since the master clock is only one for both wires then the slave clock might look for the sampling marks in any of the wires ion case it reads samples from AES/EBU. In case the clock reference delivered to slave clock by own 75-ohm BNC word clock cable this cable can care ANY sampling frequency as long phase-wise it reflects the masterclock.

I think this is why Pacific Microsonics  Model 2 does not output 176K clock and Model 1 does not output 88K clock. In fact I do not think that Model 2 even has 176K clock and Model 1 has 88K clock. They most likely have 44K and 48K (1X) clocks and multipliers. So, it is very possible that my concern about the half/clocking in dual-wire mode with Pacific was just my own self-inflicted worry.

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