Digital Room Correction - Friend or Foe?
Room interaction plays a huge part in how sound is perceived at the listening position. Even the best speakers are hampered by in-room resonance and reflections that bloat or obscure the sound at certain frequencies. In an ideal world, our rooms would be capable of a reasonably flat line audio response between 20Hz-15KHz (the audible range for most of us); the reality however is often far from this proposed optimum. Digital correction software works by playing a full-range frequency sweep, recording the response with a measurement microphone, and then inverting the measured response, thus smoothing room response artifacts.
Initial experiments were performed on the free open source DRC program called ACXO that unfortunately does not appear to support Vista 64 properly. The measuring aspect works fine on the Vista 64-bit OS; however, attempting to apply correction causes the program to hang without ever making a change. If you're using Vista 32 or XP 32-bit, we'd recommend you check it out.
As attempts to use ACXO with Vista 64 failed, I decided to go with the full version of Audiolense 3.0 for two-channel setups. The cost for the basic single user license is around $190, which is not exactly cheap for most of us, but we must recognize the level of work that goes into creating and supporting such products. There are a few alternatives to Audiolense varying in complexity, ease of use, and of course cost. For example, Acourate is a standalone package which seems to have more complexity to its GUIs than Audiolense, although there are video tutorials available on the Acourate website to help users get started.
The beauty of both Audiolense and Acourate is that both companies are new budding enterprises, which leads to support being handled directly by the authors of the software. We hope this continues as emails are currently handled within hours of being sent. Another software option is Art Teknika's Console that can be used with the Voxengo Curve Eq plug-in and used for DRC. The expansion possibilities with Console are huge, with plug-ins supporting digital crossovers and rerouting of input and output signals as long as the hardware used is capable.
Note that all of the software mentioned here features 30 day trial versions with limited functionality to give you a taste of what DRC is all about, so if you're interested but don't want to plunk down hundreds of dollars on something you might not like that's a nice option. You'll also need a measurement microphone and preamplifier. We're using the affordable Behringer ECM8000 and UB802 (now discontinued) to take room response measurements. In all, expect to fork out an additional $150 for these two components. The microphone preamp needs to support "Phantom 48V power" if you're using the ECM8000, so make sure you buy one that's compatible with this requirement.
Facebook
Twitter
RSS
114 Comments
View All Comments
Clauzii - Monday, December 1, 2008 - link
.. I can recommend a Terratec Phase 22. No computernoise whatsoever. Pure, clean sound. I don't have a surroundsetup, but movies through this card sound brilliant, with a lot of detail and no digital 'fnitter-fnatter'.Clauzii - Monday, December 1, 2008 - link
Have to correct myself: With the card You can actually hear all the bad mixing of the movies themselves.daar - Monday, December 1, 2008 - link
Honestly, for a tech review site, I'm very disappointed that you nixed any pro sound cards and went for the audiophile kool-aid. Proper regulation and filtering can deliver clean enough juice for the best audio applications and while the USB option is kind of interesting, it creates more clutter, is more expensive, and the supposed better quality can't even be objectively tested.There wasn't even an attempt to build a measurement procedure, and while some sustain the notion that audio is beyond measurement, since when does AT throw out standard science and efficient engineering in favor of pseudoscience?
RobinBee - Monday, December 1, 2008 - link
"Proper regulation and filtering"Yes. A good motherboard does this. And: A hi-fi sound card such as ASUS Xonar D2 (PCI bus) delivers »clean juice«, very much better than Creative's x-fi. And: A good case makes a pc rather quiet.
RagingDragon - Saturday, December 6, 2008 - link
And a sufficiently powerful amp and/or headphones with good isolation make PC noise irrelevant.Servant of Shodan - Monday, December 1, 2008 - link
Not meaning any disrespect to the author - it was a good article - but I've notice a lot of camera reviews recently, and now a review about audiophile stuff... and it just seems so out of place for a PC enthusiast site.There are hundreds of credible sites for both cameras and stereos/speakers/amps/etc.; and I feel that it sort of muddies the waters here to have these types of articles, when there are other excellent places where they fit in perfectly.
I come to Anandtech for computers. I think it should keep to that topic.
SpeedyVV - Monday, December 1, 2008 - link
Holy cow, audiophiles i think are THX certifiable!!!Can you guys actually hear yourselves???
All joking aside, I love music, and sound, and guitar tube amps, a nice hi-fi.
But the stuff you guys talk about is way, WAY, beyond me ;-)
Boushh - Monday, December 1, 2008 - link
DRC does realy work. Last year I exchanged my old SONY AV receiver for a new Denon AVR-3808 with Audyssey. With the SONY I was unable to get a good sound at my listning postion (specialy the rears never actually worked). And even though I had my reservations for things like Audyssey, I ran it on the Denon. And low and behold: Now I was in the middle of everything. I was realy amazed that taking some samples with a microphone could have such impressive results.The second thing: DAC's for computers. I recently saw that Cambridge Audio released a DAC for (among other things) computers (http://www.cambridgeaudio.com/summary.php?PID=320&...">http://www.cambridgeaudio.com/summary.php?PID=320&.... Maybe a good idea to compare that to the setup used in the article. It seems to me that instead of all those components it would (for the most of us) be alot easier if it was just in one box. But maybe that is just me :-)
Anyway, nice article. It shows that people who are intrested in audio and are willing to do something for it are always on a never ending road B-)
strikeback03 - Monday, December 1, 2008 - link
... that this article shows that looks are not everything, as those drivers look like the cheap junk that comes in stock car systems.jabber - Monday, December 1, 2008 - link
They probably are! Remember in the world of 'high-end hi-fi' you build a component out of $20 worth of bits, stick a bit of varnish sanded wood on it then add on the 2000% 'hi-fi mug tax'.Its one of the best businesses to be in if you are unprincipled and lazy.
Your customers are easy because they have invested so much money in their systems they are always open to fear and doubt about it. Easy prey!