I am trying to connect my MacBook to the SA30 to be able to stream a frequency sweep audio signal from the REW application to test the frequency response curve of DIRAC/speakers.
How do you connect the SA30 to a laptop for direct audio streaming?
There are several possibilities: USB, Micro USB and HDMI on the back of the SA30.
On my AVR-850, I did this with HDMI and it was simple - really struggling with the SA30 to carry out a fairly simple task.
The USB ports are for storage devices and maintenance only, at least with the current firmware anyway.
An optical cable, using either an optical out from your laptop, or via a USB to optical convertor box plugged into it, is probably the best way to do this.
If our amp is connected to your network, the Dirac Live software will allow you to perform the sweeps directly over the network.
My understanding of Dirac is the following:
Dirac carries out a frequency sweep to the Arcam SA30 and provides the uncorrected response.
Dirac then corrects this response to the target curve and calculates a predicted frequency response.
What it doesn’t seem to do is provide another frequency sweep to show you the actual corrected frequency response, which is what I am using the REW application to carry out.
I wonder why Dirac doesn’t do this?
It doesn’t, as Dirac is for correction, not measurement 
Never really seen room correction, that would measure AFTER correction is dane. In Dirac you can also change/alter the curve, so it would have to do another sweep after filter is ready. Question is, what would be the benefit of this, except for satisfying your curiosity. I don’t think it would be possible to make more adjustments based on this additional sweep.
So it would be only for you.
As others said, USB ports on SA30 are not DAC inputs (wonder why actually, on early photos micro USB port was marked as “USB audio” I think), so your only option is either analogue or spdif.
Or something like this:
Exactly! My question too! My guess, they are so sure that the actual response will match their filter that it is redundant. But I too would like to see the actual result as I suspect it changes at different volume levels.
Ken
There are a variety of ways to achieve this.
Some MacBook models have a Toslink digital output built into their headphone ports (obviously you need the right cable). This can plug directly into an optical input on the SA30.
Or, you can use ethernet (probably requires a dongle to convert the USB ports to ethernet).
Or, by far the easiest, connect your network router to the SA30 by ethernet and send the output to the SA30 by airplay. In fact, since the SA30 will appear as a wireless endpoint on airplay wireless networks, this can work without ethernet on a standard airplay wireless network.
The downside of using airplay (for purists) is that music is transmitted using the apple lossless codec which limits the transmission rate. But i’d be interested to see how many can tell the difference in quality (I’m experimenting with Tidal MCQ and other known sources of high quality streams using a laptop’s digital out versus airplay streaming to see whether i can tell the difference).