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Here's some more background.

The inventor of the underlying technology is an engineer named Chris Kyriakakis, a guy with lots of impressive paper on the wall. It's a familiar story: an academic, working on the public payroll and using free student labor for assistance, develops a concept that has commercial potential and cashes in. Can't blame him. An EE professor's wages aren't going to pay for a home in Malibu.

IK isn't about to give many technical details, but it is a patented process and therefore public information. Mr. Kyriakakis, along with his graduate student Sunil Bharitkar, holds two relevant patents:

Combined multirate-based and fir-based filtering technique for room acoustic equalization

Room acoustic response modeling and equalization with linear predictive coding and parametric filters

The first one is for a FIR filter that applies less equalization to low frequencies than to high frequencies. It doesn't really sound like a patentable innovation to me, but then most electronics and software patents don't. I probably couldn't be a patent examiner.

The second one is the other part of the ARC system: the measurement part. It's for an algorithm for automatically determining the amount of cut/boost and Q for each parametric filter. Here's the actual abstract:

A method for determining coefficients of a family of cascaded second order Infinite Impulse Response (IIR) parametric filters used for equalizing a room response. The method includes determining parameters of each IIR parametric filter from poles or roots of a reasonably high-order Linear Predictive Coding (LPC) model. The LPC model is able to accurately model the low-frequency room response modes providing better equalization of loudspeaker and room acoustics, particularly at the low frequencies. Advantages of the method include fast and efficient computation of the LPC model using a Levinson-Durbin recursion to solve the normal equations that arise from the least squares formulation. Due to possible band interactions between the cascaded IIR parametric filters, the method further includes optimizing the Q value of each filter to better equalize the room response.

So how does this differ from any other parametric equalizer? I haven't waded through the entire patent document yet, so I would encourage others to dive in. So far, I have not seen any magic fairy dust described. At the end of the process, it's a multi-band parametric equalizer that's been automatically configured for you based on weighted measurements.

As with any patent application, there is a lot of obfuscation designed to make simple principles sound unique -- uniqueness being necessary to obtain a patent. It will take a lot of wading through the mumbo-jumbo to separate the obfuscation from what's truly unique. Have fun!

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Here's an interview with Chris K. I have not seen it, as I refuse to install the QuickTime virus on my computer. Let us know if it's any good.

Here's an IK salesman giving his take on ARC. He says it was developed by the "same team" that created THX. I haven't pursued that claim. He's conservative in his claims, saying if you have an acoustically-treated room, ARC provides the last "1 percent". His best statement: "when I take the CD out to my car it still sucks but it sucks less."

Here's a moderately positive review by Craig Anderton. Good screenshots and description of the measurement process.

We purchased this product over a year ago.

Following the lengthy calibration stage we applied it to the master bus. To be honest it sounded terrible.

The worst thing is it appears to overcompensate for some of the correction and also produces phase shifts that any quality mastering eq would never have.


The thing that frustrated me is you cannot adjust the correction in any way. For instance the Ozone matching algoriithm lets you smooth the correction curve and set the correction percentage.
That's just not possible with this plugin.

If this pluging had a better quality eq and you could adjust the correction amount then it would be much more useful.

I can't knock it's ability to show some room problems, but it needs more controls and a lower price tag to be something I'd want to recommend.

Just came back to this post, and nice to find someone willfully misinterpreting my post in order to further there own views.

Yes Mike McCue, this ones foryou.

I'm just pointing out that one potential endorser isn't even using it correctly... (in fact he's now using it in the most regrettable way) and yet he thinks it's the "mutts nutts".

So I'm just wondering if that's really an endorsement.

Like they say... it's only money. :-)

You have made an assumption, I said that I have not had the time to re-calibrate it to the new layout of my room. You assume I still have it switched on when I mix, and that is where you have made an assumption and got it completely wrong.

I realize that for the ARC to work it must be re-calibrated everytime you move your speakers, and or set-up, since I moved them all to allow a relative to stay with me, I have turned ARC off and do not use it. I will not untill I have time to re-calibrate.

However when I intially set it up and took a lot of time about it, and marked out all my measurement points very carefully (please look up another thread where I actually go into my methods in quite some detail) then it was the mutts nutts and made a very real difference to my room.

Yes a better room and some acoustic treatment would probably make more of an improvement, but given my restrictions I have been very happy with it.

So please in future before jumping to conclusions about other forum uses abilities and competance, maybe think a second, becuase you came accross as an arrogant idiot with your post.

G

I'm guessing, that if you put the plug in on the masterbus AFTER doing a mix, then it will sound awful. It probably should go on the masterbus after tracking and before starting the mix.

Don't forget to take the plug in out before exporting.

If nothing else it provides a good view of the room impact on a mix.

I really don't see what all the fuss is about...if it adds value to you, then use it, if you don't think it does, then don't use it.

Nothing is the perfect answer, even a fully treated room will likely have some issues, even if they are small.

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Apologies, for using the word idiot. That was uneccessary.

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