[sdiy] USAMO

Nantonos nantonos at epona.net
Thu Mar 26 16:24:58 CET 2015

Hello Ove,

Thursday, March 26, 2015, 3:46:30 PM, you wrote:

> On 26 March 2015 at 15:12, Nantonos <nantonos at epona.net> wrote:
>> As a standalone box, its not sample-accurate with anything else.

> I think you are perhaps misreading the claim? In the simplest setup,
> you have an audio interface with one audio channel outputting audio,
> and one audio channel outputting encoded MIDI to this box. Assuming
> the channels of your audio interface are locked to each other, you can
> predictably start an audio sample and a MIDI message at the same
> sample position, on the two different channels.

Yes. I was thinking more of synchronisation at the output of this box,
but you are correct that it is reasonable to assume adequate
synchronisation between audio channels at the output of the audio
interface (input to this box).

> You could also start
> the MIDI message one sample position later etc. You would still have a
> decoding delay,

Right. Unless that decoding delay is under 5us (at 96kHz) then it is
no longer sample-accurate.

I'm perfectly fine with Expert Sleepers advertising that their box is
significantly better than alternative methods of sending MIDI data
(ideally with measurements to support their claim). I do feel that the
specific term "sample accurate" has a specific meaning, i,.e. less
than 0.5 of the sample period, and that this is a misleading claim.

>  but if this box is well designed, this delay will be
> constant and can be compensated by sending the MIDI message earlier if
> you need/want such precision.

I'm not clear how one would introduce such a timing offset, could you
give an example? (Not saying it can't be done, just that I don't know
how it would be done and have never seen that function in the DAWs
which I use - Studio one 2 and Reaper).

>  You would only need a wordclock if you
> wanted to sync multiple DACs/ADCs so the sample input/output doesn't
> drift between individual DACs/ADCs.


Best regards,
 Nantonos                            mailto:nantonos at epona.net

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