07-Dec-2014, 12:32
I think I need to stand corrected! Dirac does indeed claim to offer phase correction. Although as I said, I have never tried Dirac, so obviously I cannot comment on its capabilities. It should be noted that there is a Dirac / Room correction thread on this very forum. If anyone does have any good information regarding Dirac or any other room correction software / systems then it would be good to see this. I had a quick read through the thread, and it left me wanting more decent information and feedback!
I think the point re SAM is that it is done in almost laboratory conditions using professional equipment. I did spend some time talking to Devialet's chief designer about SAM. As well as the obvious sound equipment they use laser scanners to monitor cone movement. The SAM process is also quite labour intensive, taking maybe three man-days per speaker. The phase correction is genuinely real time. So for example, if with a particular input signal the bass driver is reacting too slowly, the DSP model of the speaker will actually provide the signal / current to the bass driver slightly before it actually occurs in the music. (Using the buffering and processing, not time travel, Devialet haven't cracked this one yet.) I have spent some time now with "SAM enabled" speakers, and I can attest that that on occasion it's effects are extraordinary, you can hear the accuracy of the implementation, you can then turn SAM off and hear what's gone.
As I said at the start of this post, I am not an expert regarding the capabilities of Dirac. However, I suspect that when you look at what is involved with SAM and its implementation, then this is going to be difficult to match at home, in particular when you look at the accuracy SAM that can achieve with the phase correction etc. As for room correction, well SAM doesn't do it, so third party software, or good old fashioned room conditioning etc. are all we are left with.
For those with experience of Dirac and similar, keep the feedback rolling in. It's an interesting topic, and the existing thread covering Dirac on this forum could certainly do with more input from those with hard earned experience.
I think the point re SAM is that it is done in almost laboratory conditions using professional equipment. I did spend some time talking to Devialet's chief designer about SAM. As well as the obvious sound equipment they use laser scanners to monitor cone movement. The SAM process is also quite labour intensive, taking maybe three man-days per speaker. The phase correction is genuinely real time. So for example, if with a particular input signal the bass driver is reacting too slowly, the DSP model of the speaker will actually provide the signal / current to the bass driver slightly before it actually occurs in the music. (Using the buffering and processing, not time travel, Devialet haven't cracked this one yet.) I have spent some time now with "SAM enabled" speakers, and I can attest that that on occasion it's effects are extraordinary, you can hear the accuracy of the implementation, you can then turn SAM off and hear what's gone.
As I said at the start of this post, I am not an expert regarding the capabilities of Dirac. However, I suspect that when you look at what is involved with SAM and its implementation, then this is going to be difficult to match at home, in particular when you look at the accuracy SAM that can achieve with the phase correction etc. As for room correction, well SAM doesn't do it, so third party software, or good old fashioned room conditioning etc. are all we are left with.
For those with experience of Dirac and similar, keep the feedback rolling in. It's an interesting topic, and the existing thread covering Dirac on this forum could certainly do with more input from those with hard earned experience.
