Dirac and room correction software

[Borgen]

You could have a look at Audiolense, I tried it a few years ago and it looked promising. I don't know how active it is being developed these days, but the quality back then was quite ok.

[Hifi_swlon]

I began a search for software solutions early December that could be used to generate FIR filters for use with miniDSP units for room correction/speaker voicing.  I downloaded appropriate trial, demo or evaluation files and tried each with a straight forward example.  Before the Christmas break, I had reduced the field down to FIR Designer, Filter Hose and rePhase.  Personally, I find the first very intuitive to use with all the steps simply laid out.  It's reasonably priced and there have been five updates during December.
I hope to continue testing mid January but think FIR Designer will be hard to beat.

Thanks for the tips, will check those out, especially FIR designer. Looking forward to hearing your impressions - what did you use to test the filters in playback?

...[edit]...

OK found it, posting here in case its useful http://eclipseaudio.com.au/fir-designer/

I like the look of it already. Not sure why it didn't come up in any of my searches so far...


....

Mmmm having now had a good read through I just don't think I'd have the patience for it. I guess I'll just sit tight until Dirac one day materialises in my preferred playback package.

[thumb5]

Been thinking along similar lines as I'm going to experiment with using a headless Mac Mini for streaming rather than using my "daily driver" MacBook Pro.  I've only scratched the surface here but as far as I can glean from a quick bit of reading around it looks as though on a Mac the "right" format for a filter is an Audio Unit (AU) plug-in.  It seems that Audirvana (for example) can process these directly.  Unfortunately not so for Roon, if I read it right.

One thing that caught my eye is this: FabFilter Pro-Q 2.  It's obviously designed for music production rather than room correction during playback, but might be worth a bit of experimenting with.  Seems quite reasonably priced.  OK, I'll own up: the 8-minute video had me hooked; it's great fun even if you have little or no interest in room correction!

I'll probably give Dirac another try first, though - closed format or not, it's much more appealing if I can run the DAP on a dedicated machine.

[SwissBear]

Another option is to use the combination of REW and rePhase to reach the same goal as Dirac for free. You will be able to produce correction impulses that you can use with JRiver or HQPlayer.

Here is a brief overview how to do it: http://www.computeraudiophile.com/f23-ds...ons-30760/

In case you need help, don't hesitate to ask

[Hifi_swlon]

Ian, fab filter looks very cool! Not sure it can export filters to use in convolution engines though?

Swissbear, will take a look at your link.

I guess my issue with all of them is they're just so damned complicated! I don't want to learn the intricacies of it all or get a PhD, I just want the best sound I can get from a few measurements. If only Dirac could export filters.....

[thumb5]

Ian, fab filter looks very cool! Not sure it can export filters to use in convolution engines though?

Swissbear, will take a look at your link.

I guess my issue with all of them is they're just so damned complicated! I don't want to learn the intricacies of it all or get a PhD, I just want the best sound I can get from a few measurements. If only Dirac could export filters.....

Mmm - I got the impression that the whole thing ran as a plug-in, including the UI which allows you to change the EQ in real time, so you need something to "host" it. I've read several posts on CA and the Audirvana forum saying that A+ can host it. Of course the proof is in the pudding. As it happens I've just started a trial of A+ and the Pro-2 plug-in can also be evaluated for 30 days so I could try and plug it together and see what happens...

I agree about the complication though. That's why I keep thinking Dirac is probably the way forward: it seemed to be very easy to use when I tried it. Is your concern about its closed nature mainly on philosophical grounds or a practical worry that you won't be very "future-proof" if you use it?

[Hifi_swlon]

Not philosophical grounds. Just that I want to do EQ in Roon and to my RoonReady device. So no Dirac sadly (at least not in the near future).

[thumb5]

Well, that was easy!



With that "Realtime..." checkbox ticked, the filter UI comes up and the filter can be configured while the track is playing.



Very impressive!  If you know what filter you want, of course.

[thumb5]

Now if the Roon chaps would make it host AU (or similar) plug-ins, you'd be laughing. That's been discussed, I know, but I didn't work out whether or not it was on the roadmap.

[SwissBear]

If the goal is a very good room correction, it should, IMO, also embark correction in the time domain. This would ensure that all the drivers of your speakers are time-aligned and that the sound reaches your ears at the same time, whatever the frequency.

This is one of the major sales-points of Dirac.

To illustrate, with a loudspeaker which range goes down to 20Hz, you are expecting your system to produce an impulse/step response like this:

[img][/img]

and what a non corrected speaker produces looks like this (B&W 802D3): the first peak is the tweeter, the second the medium and the third the woofer:

[img][/img]

With a time domain correction, you will get something like this:

[img][/img]

So, with the correction, all the drivers of your LS are aligned, and the acoustic benefit is a much deeper sound stage (sounds like 3D), and a much better separation between the instruments, voices, aso...

To reach this, you mainly have four options:

• Trinnov hardware (excellent option, but expensive)
  
• Dirac software (excellent option but need to use their software during playback with a license which is not exactly hassle free
  
• Acourate (very easy to setup and to use, even without a PhD). The only difficulty is that you need a machine running under Windows (or Mac + Parallel/VMWare) to run the measurements and to produce the correction. Once you have the correction, you have no limitation related to license and can use you whatever system you want to reproduce it. There is an extensive demonstration of Acourate in the field of room correction here: http://www.computeraudiophile.com/conten...lkthrough/
  
• REW/rePhase which does the same, at the cost of a deeper understanding of what you are doing. But this is a free and highly customizable solution.
  

In the last two cases, the correction process involves impulses. You can make the convolution of these impulses with your music using JRiver or Roon/HQPlayer.

There is an extensive coverage of the latter here (http://www.computeraudiophile.com/f11-so...yer-20293/) and in the adjacent threads. The quality of HQPlayer playback, together with the ease of use of Roon, has gathered a lot of interest it seems.

If you are interested in testing a correction made with REW/rePhase, just send me a link which allows me to download the measurements you have made with REW. I will have a look at it and hopefully be able to make a correction proposal.