Dirac Live 3 room-correction software

Adoption of DSP-based speaker-and-room correction in home theater—a parallel universe to audiophilia—is almost universal. It's easy to understand why. Home theater matured in the digital age. Its fans were expected to install several loudspeakers in a full-range setup that included at least one speaker—the subwoofer(s)—that functioned exclusively in the problematic bass region. Setup issues were intimidating.

Help quickly came in the form of setup utilities that required no knowledge of acoustics—only a willingness to position a microphone for a series of measurements and let the system do the rest. Audyssey was the first such utility to gain wide acceptance. Today, some arrive installed in AVRs and preamp-processors; others come as standalone devices or computer software. Most work well, providing precise level balance, compensating for unequal pathlength differences, and correcting in-room frequency response for all the speakers.

In the two-channel world, things have proceeded much more slowly. I can think of several reasons. There are fewer speakers to integrate. Small, standmount speakers often benefit from uncorrected room modes to extend their range. Stereo listeners are much more likely to integrate analog sources—turntables, reel-to-reel tape, and old-fashioned radio tuners—into their systems and to resist converting that pure analog signal to digital so that it can be processed and room-corrected. And yet, these days, most two-channel audiophiles spend at least some of their time listening to digital, whether it's from a streaming service, locally stored downloaded or ripped files, or old-fashioned shiny silverdiscs. There's a place in the two-channel world for room-correction DSP.

Dirac Live (the original)
When it first appeared, Dirac Live was a software product that the user could buy, download, and install into a Windows or Mac computer used for music playback (footnote 1). As such, its use was limited to the more intrepid and technical audio consumers. For those of us who accepted the job, it was an ear-opener. Not only was it more flexible and precise than those convenient built-in products; it was audibly more capable of dealing with problematic room effects. I reviewed the original release of the Dirac Live Correction System (DLCS) in 2014 and installed it into both my systems, for multichannel and stereo.

In its original implementation, the Dirac Audio Processor (DAP) acted as a virtual audio device, inserted into the signal chain between your music program and your DAC. The DAP accepted only PCM sources (no DSD) and, at the time of the review, only up to 24/96. The other half of DLCS, the Dirac Live Correction Tool (DLCT), was used to conduct measurements and create filters. Those filters were uploaded to the DAP, which applied them speaker by speaker to the music being played back. I loved it.

Over time, DL added support for 24/192 PCM, expanded its hardware compatibility, and introduced a VST plug-in version of the DAP. Notably missing still was bass management. It's still missing, but not for long. (See sidebar, Dirac Live Bass Control.)

Dirac Live 3
I stayed in touch with the Dirac team. After a while, the responses to my questions and requests shifted from answers and fixes to intimations that they were directing their energy to a new product. At the 2018 Munich show, I had a long conversation with Jakob Ågren, Dirac Live's head of product management. He intimated that all my requests would be fulfilled by a new version of Dirac Live—but they'd be directing their earliest efforts to creating an embedded app for AVRs and prepros—not computer applications. It was, I'm sure, a wise business decision, but it wasn't what I wanted.

Dirac Live 3 is finally here, not only on many hardware platforms but, finally, as a PC and Mac application. As promised, it offers many enhancements over earlier Dirac software, with more promised.

The Dirac system still has two components: the Dirac Live Processor (DLP, formerly the DAP), which applies the filter corrections to music as it plays. In PCs and Macs, it can be installed as a plug-in or as a regular application. Plug-in support is not universal, but JRiver, Audirvana Studio, Amarra, and most DAWs support it.

Many computer-based music apps can work with the standalone Dirac Processor. The processor module appears as a virtual soundcard (limited to 8 channels) and becomes the computer's default output device. The actual target device—the DAC—is specified in the Dirac Processor. There's no reason why this configuration should not work with all music players and the desktop apps of streaming services, but I could not get it to work with Roon (footnote 2). I used it successfully with JRiver, Apple Music, and Qobuz (up to 192kHz). A warning: The standalone application routes all sounds, including notifications, through the Dirac Processor to your system. If you don't turn off all system sounds, you and your neighbors risk ear-popping beeps, bells, and swooshes with the arrival of each new e-mail or the insertion of a USB drive.

The second component, Dirac Live (formerly DLCT), makes all the measurements and generates the corrections. You pay for the DP: $349 for a stereo license, $499 for multichannel. DL is a free download.

Up and running
Dirac provides a detailed, step-by-step user manual; here, I present a summary of how it worked for me in actual use.

With a PC or a Mac, you install the Dirac Processor first; once that's set up, the Dirac Live 3 calibration component recognizes and conforms to the channel/speaker configuration you specified in the Dirac Processor. I installed the Dirac Processor as a VST3 plug-in in JRiver (accepting all the defaults) and did most of my testing and listening that way. After starting up JRiver, I navigated to its DSP Studio menu, clicked on "Manage Plug-ins," and selected "Add JRiver, VST or WinAmp plug-ins." A window opened to the default location, and I selected DiracLiveProcessor.vst3.

Up popped the Dirac app menu, with eight empty slots for correction filters, a gain control, and a dropdown list of 29 channel formats from mono to 7.1.2. Included on that list were quadraphonic as well as Ambisonics, first through fifth order! 5.1 was my choice (footnote 3).

Footnote 1: The original Dirac Live was also offered in the Theta Casablanca IV, the Datasat RS20i, and the Emotiva XMC-1. A limited version of the current app is included with the NAD M10 integrated amplifier; see here.

Footnote 2: Dirac seemed puzzled. Roon seemed uninterested.

Footnote 3: Supported configurations for the plug-in are 2.0, 2.1, 3.1, 4.1, 5.0, 5.1, 5.0.2, 5.1.2, 6.0, 6.1, 7.0, 7.1, 7.0.2, 7.1.2, Quadraphonic, Pentagonal, Hexagonal, Octagonal, Ambisonic. The Standalone is limited to 8 channels.

Dirac Research AB
Stationsgatan 23-25
753 40 Uppsala, Sweden
+46 18 4108210

Mike-48's picture

Kal, I enjoyed the review and am thankful for your continued interest in DSP applied to audio. To clarify what you wrote about DLBC, my impression is that it sums bass to mono?

Kal Rubinson's picture

EDIT:Ah. DLBC is a bass management system and it will take the bass from each channel and distribute the sum to all the subs. If you want to control what signal goes to each sub (e.g., stereo subs), you need to do that yourself (e.g., in JRiver) and use an alternative mode of DL.

It treats as many subs as you have channels for as independent sources. Note that each sub must have its own channel independent designation and wire connection.

For example, I am using 5 main channels (L,R,C,Ls,Rs) and three subs, so I use an 8 channel layout L,R,C,Sub1,Ls,Rs,Sub2,Sub3).

Mike-48's picture

Thanks for the reply, Kal. I have been running 2 subs in stereo, on the theory that if the bass on a recording is in mono, it will be reproduced fine, and if in stereo, any added ambiance will be nice. If I had to bet, I'd guess they are very hard to distinguish. Indeed, a recently added 3rd sub is run in mono with no decrease in ambiance to my (ageing) ears.

Bob Loblaw's picture

I wish there was more hardware on the market that could be placed between a source and a DAC to provide room correction. I have a Paradigm PW Link which uses Anthem's ARC room correction, but it has some idiosyncrasies to the way it works.
MiniDSP makes the DDRC-24, but it only has analog outputs, and they also have the DDRC-22D, which is exactly what I'm looking for, but expensive in Canada at $1,170 for just room correction. Hopefully more hardware will come to market to fill this niche.

Mike-48's picture

If you mean digital only, stereo only (including 2.1 or 2.2), the miniDSP SHD Studio is a little cheaper than the unit you mentioned and runs Dirac.

Bob Loblaw's picture

That's interesting. I use Squeezeboxes around the house still, but it looks like you can run Squeezelite on the SHD Studio which could eliminate an extra box. Thanks for the heads up.

thatguy's picture

That PW Link could be great if they could fix the little bugs to it.

I would also like a quality 2 channel hardware option that was a bit more affordable for adding Dirac Live3 to my signal chain.

thatguy's picture

I think room correction is the next frontier in 2 channel audio. Articles like this are very helpful; especially the tips on the Harmon curve.

How do the hardware based options (miniDSP) with it built in compare to the PC setup?

Mike-48's picture

One audiophile's opinion: Both hardware systems and systems run on a PC have their advantages. For stereo, dedicated hardware can be easier to set up in terms of connections and abilitites. For example, the miniDSP SHD or Anthem STR have four outputs, 2 for mains and 2 for subs. That can be tricky to configure on a PC (not impossible by any means). Hardware solutions might be incorporated into a preamp with source switching, ADC, volume control, and possibly tone controls for quick adjustments. (When I was looking into a PC-based solution years ago, source selection was a stumbling block.) Finally, dedicated audio units don't require having a PC in the listening room, which some find a distraction.

I think PC-based solutions have the advantage in maximum flexibility and configurability and the ability to add more processing power in the future. You can even change DSP system, if you want, without changing hardware. I suspect also they can be more cost-effective. But to my mind, they are a little more towards the DIY end of the spectrum.

partain's picture

I've been chasing "flat" response for 50 years , and now I find a little bass and treble boost is good ? Back when tone controls existed I used a bit of boost on both ends but I was soon educated out of that nonsense . If I stray too far from flat now I'm afraid I'll feel guilty . Old habits .
Will you get the bass thingie later for free if you buy in now ?
And what about Tidal ?

Kal Rubinson's picture

I've been chasing "flat" response for 50 years , and now I find a little bass and treble boost is good ? Back when tone controls existed I used a bit of boost on both ends but I was soon educated out of that nonsense.

Time marches on but it is a little bass boost and a little treble roll-off.


Will you get the bass thingie later for free if you buy in now ?

Possible but I doubt it.


And what about Tidal ?

Tidal (which I do not use) is just another app. I am guessing that it will work with DL3 the same way that Qobuz does.

doxsoundlv@gmail.com's picture

Running a 2.2 system in my office control room style. Elac Unifi UB5's and Klipsch RPW10 subs fed from my near 20 year old Denon 3802, via a Parasound ZDDAC and J River. With Dirac installed the focus and imaging is much better, and the bass is not so boomy (these are inexpensive subs after all). I think it's a kickass system for very little money and probably about as good as it's going to get in my tiny room. I did the calibration with a DBX RTA mic I had from my pro days, and an ART mic pre to USB, but have a Focusrite on the way that might make a difference...we'll see.

luh3417's picture

For several months, Dirac has been developing a new version for the Mac, that doesn’t use plugins, and instead simply works as a kind of virtual sound card, for all audio output. I’ll buy it then, since I want to use it with Amazon Music, which doesn’t support plugins.

(There’s probably a complicated poorly documented rain dance I could undertake, to make the current version work with Amazon Music, but I’m thinking to just wait for the new version.)

(I think the Windows version is already there and doesn’t need this new architecture).

Here’s instructions for installing the Mac beta https://confluence.dirac.services/display/DLS/macOS%3A+Standalone+Beta

They are updating regularly, latest version is here

Kal Rubinson's picture

Yes, the Windows version is already there and the new Mac version (which I cannot test) has been announced.

luh3417's picture

Is the new Mac version for sale yet? Have they announced a target date? I don’t see it on their website. I have to say I still find their product offerings beyond confusing. OK I see “Plugin and Standalone for Windows and I see Plugin for Mac” so yes what I’m waiting for will be called “Standalone for Mac”.

Some of the new Onkyo AVRs will come with Dirac. Saw that announced somewhere. Ought to give Denon with Audyssey a run for its money. I don’t see this on their website either though.

nuitamericain's picture

Thanks so much for this very informative and useful review. I can't run Dirac from software, due to a need to play movies and DVDs from my Bluray player rather than my Mac. Are there decent options for hardware playback in a high-end 2-channel setup (with subs), please - ideally with Roon endpoint capability and HDMI input? Also, could I ask is there any benefit in such a hardware solution sitting before my current DAC and outputting room-corrected digital for further processing? Lastly, I'm not sure if this is mentioned, but is any extra headroom demanded of power amps with house curves (bass boost), or is this actually done by taking down the relative level of the treble?