Datasat RS20i BETA test and comparison with ADA Rhapsody/Trinnov TEQ-12!!!! - Page 9

Well, reading about the problem, I think it is the opposite . I would get the Datasat folks to troubleshoot this. Billions of devices plug into USB and work without needing three reboots. And even if Windows is the issue, they need to work around it. Sounds to me like a driver problem with the dongle of the USB interface to the device.

And what is the deal with the security dongle? Why isn't the processor the "security dongle?" Who would be stealing this software anyway? Is it to guard against people buying the commercial unit and then trying to use this software with it?

Sorry Dan. I usually don't defend my ex-employer but your comment seemed a bit unfair toward them . I realize I was shooting the messenger so sorry about that.

Interesting.

In case it wasn't obvious we also have both of these available in our PHC/PRO Audio demo room right now. My own thought is that in pure performance one is clear winner but the other looks an interesting value. I would never in a million years sell these as auto cal products though - although I would say the same for Audyssey!

Congrats Dan for walking the talk and your diligence to set-up a true processor right

I am curious--were you able to compare the two units sonically without engaging with Dirac Live and Trinnov respectively.

Regards,
Kishore

Did you contact Trinnov about this?I can't find any info on a search that states that Trinnov uses a mixed-phase correction approach.

I found a review from the UK 2008 reviewing their previous flagship professional Optimizer unit and it mentions only linear phase and minimum-phase filters.

During the calibration,presets were created for a variety of different configurations: a system bypass,three full correction settings with varying levels of reflection cancelling,two further versions with 2D and 3D speaker position correction,one setting used minimum-phase filters(instead of the default linear phase),and one for a simple stereo arrangement.

http://www.sound-link.co.uk/pdf/LineUp_OPTIMIZER.pdf

I don't know if they have changed their correction filter technique since that review.

Actually ...

The Dirac Live filters in both the AP20 & RS20i are 20,480 tap FIR filters running at 96kHz 24 bit. And they are of a mixed phase nature.
_____________
Best Regards,
Carl Huff

Details on Dirac filters are discussed in their white paper, as attached.

 

Dirac On_equalization_filters.pdf 350.572265625k . file

Dan, to eliminate as many possible variables, I would test, the Datasat product with it's optimization,then turn that off and connect it to the Trinnov and compared the results. I believe that is as close as you can get to comparing optimizations systems. The ADA IV is not producing an optimization,it's just adding another independent variable. Hey but you are doing enough work. However,when you noticed a "class A sound" from the Datasat you acknowledged, at least to this former experimenter, a plausible rival hypothesis, an alternate explanation for preference. "Back in the day," I would have tested for both and did a mulitviariate analysis. That's asking way too much. Not trying to sidetrack you. Please just keep doing what you are doing. Just info.

Phase
First, I'll suggest the concept of maximum phase doesn't exist, and that this might be what we call linear or zero phase. This is where the filter time aligns all frequencies: corrects for amplitude and all phase rotation (speaker and filter). Minimum phase is where the filter doesn't correct for phase, and in addition, adds it's own additional phase rotation as a result of amplitude corrections. The EQs that everyone is used to: tone controls, graphic and parametric EQ, they are based on IIR filters. One could assume that linear/zero phase filters would always be ideal, but not the case at low frequencies. In typical rooms that affect the bass amplitude response, there is a corresponding phase rotation (in addition to the rotation that may be found in the speaker). An appropriate IIR filter used to correct the amplitude error will also correct the phase error naturally. The phase rotation of the filter will offset or counteract the speaker/room phase error.
Trinnov
We provide the user several options and combinations, as well as the ability to define the filter sizes that are used by the automatic correction algorithm. Typical setting is for a combination of FIR linear/zero phase for full band, with any range of ms or points, combined with IIR for low frequency, again with user definable setting for frequency limits and number of filters, etc. Other choices for the FIR is the ability to use minimum phase, align all speakers' phase according to Left/Right, or use of FIR or IIR alone. Align according to L/R is done when one wants to keep the sonic signature of their L/R loudspeaker and impose this on the remaining speakers (some like the sonic signature of phase rotation, with consistent rotation, speaker to speaker, for ideal for imaging).
To summarize, there are default settings, which many rely on, then if one wants to exert more control over any variable, the ability to do so is there. For comparison, one could set the Trinnov variables to match another component under test, thereby providing one with a starting point for evaluating the relative merits of the automated algorithms, which can be a very different animal all together. What the algorithm looks for in building the filters is key to the results. Ours has a number of proprietary routines that I'd love to share, but then we'd be giving away the recipe, so to speak.

That's puzzling. How could those speakers have so much response at 20 Hz? What speakers are they again?

Those links are not to your picture files, but to the image viewer that shows the pictures. Not sure if Flickr offers the owner access to the "jpg" URL, but Photobucket does.

I have noticed "loading" of the speaker in the room really changes results with Audyssey. Are the ATCs against the wall? If so that might explain the lower frequency response

Dan,

The corrected responses are certainly impressively smooth.

I forget, are they averages of several positions, or at the MLP?

If the latter, what does the response at the MLP look like?

I'm wondering about the variation throughout the listening area.

I believe ATC comes up with their specs as measured in their warehouse (i.e. very conservative). I've got a full active ATC setup with the anniversary 100 towers as my mains. I love em.

Thanks for this thread Dan. I understand that the TEQ is similar to the standalone Trinnov ST2 which I'm interested in for my 2 channel setup (the ht stuff is in the same dedicated room but uses an Anthem ssp with very decent room correction already). I read a review indicating that the Trinnov used as just an automated system offers significant improvement. I appreciate that some tweaking would improve it further. I'll find out when I demo one next month hopefully.

Yes indeed.

I realized after posting that my question wasn't germane to RC performance, as the only determinants are the speaker placements and room acoustics.

Wonder if your subs were on at the same time as LCRs.


For a center speaker?

I looked at your TEQ measurements and while it is very hard to decipher them given the very narrow vertical range, it appears that the TEQ is also seeing the high levels of low frequency energy. It might pay to listen to the tones as transmitted by the EQ system to make sure when it thinks it is exciting a speaker, that is all that is playing.

Either way, one would want an explanation before trusting the results.