Boston Section

January 17, 2008 the Boston chapter of the Audio Engineering Society held a presentation by IK Multimedia of their new acoustic correction package, ARC. IK is an Italian audio software development company with US base in Florida. Having started with the highly successful software sampler, SampleTank, in the mid 1990s, IK is perhaps best known presently for their guitar and bass amplifier modeling software: AmpliTube, Ampeg SVX, and the new AmpliTube Jimi Hendrix Edition. Acoustic Room Correction (ARC) system is an interesting take on applied equalization to compensate for control room acoustic anomalies. In this age of DIY, home studios where acoustic design is often either overlooked or relegated to the back burner for lack of adequate funds, compensation for poor mix environments with a relatively easy-to-use plug-in seems a revolutionary idea.

Regional sales representative, Daniel Boatman, explained the genesis of the system. ARC is based on technology called MultEQ licensed from a company called Audyssey Laboratories. This technology development team was headed by Professor Tomlinson Holman, who also won an Academy Award for his work in developing the THX Sound System for Lucasfilm Ltd. Apparently MultEQ has been available for high-end home theaters as part of hardware implementations for 5-6 years already, but is quite expensive and requires trained personnel to set up. For the recording studio, IK recognized the ability to implement MultEQ on the studio computer as a plug-in and rely on the expertise of the studio engineer to make the necessary measurements.

IK Multimedia sent their Hartford CT based emissary, Nick Polit, and the demonstration was held at producer Jordan Tishler's Digital Bear Entertainment studio in Boston. The software package consists of a stand-alone measurement application, a VST/AU/RTAS plug-in that applies the measured correction, and a special measurement microphone for which their measurement software is specially calibrated. In other words, you can't use just any microphone. The software installed on the DBE G5 dual 2Ghz MacIntosh rapidly and without incident; there was basic serial number type copy protection. The plug-in appeared as expected in both ProTools 7.1 and Cubase 4. The stand-alone measurement software worked like a charm; it walks you through the process of taking the 12 or more necessary measurements. It was a little unclear how to optimally place the measurement microphone. As you take measurements at different locations within the room, it would be nice to have a bit more guidance as to how far apart the spots should ideally be located. It became clear that measurements were best clustered around a listening area; the mix sweet spot, or the client couch, for example. It was best not to try to get one measurement set that encompassed too wide an area. Thankfully, the software allows you to save a correction profile (set of measurements) as a pre-set, and have as many profiles as you like. So, for example, you might have one for the mixing sweet spot and another for the client couch, and switch between them on the fly depending on who was listening critically at any given moment.

The first set of measurements showed an absolutely ruler flat response of the room, which, while a pleasing artifact to the room owner, was clearly not in keeping with the known frequency response of the room as measured some years earlier by David Moulton of Moulton Laboratories. Oddly the measurement application appeared to be getting appropriate signal. After some futzing, a more anticipated response was obtained showing nearly flat response with a few anomalies in the 20-40Hz range. The measurement application was then able to apply its correction which reduced the low frequency issues by about 3dB, but not entirely. Further, the application was able to compensate for some, though not all, of the phase problems in the low frequencies created by the inherent asymmetry of the control room.

Applying the room correction is as simple as pulling up the ARC plug-in as the last plug-in on your DAW mix bus, and selecting the pre-set you want. Suddenly the high frequencies seemed clearer and the very low end felt tighter. The system was auditioned with several completed mixes from the studio and from AES members' CDs. Audition material ranged from acoustic rock to "Broadway" metal. In each case, subtle but real clarity was noted in the highs and lows. In general, attendees appeared to be quite impressed. Unfortunately, given the nature of these presentations, there was no opportunity to make an actual mix and see how decisions might have been affected by the ARC system. Of course, that is the acid test: whether the compensation make it easier to get good mixes that translate well to other listening environments. However, the improvement noted in the finished masters was very encouraging.

IK Multimedia is generously offering Boston AES members the chance to purchase the ARC system at a discount following their demonstration. Any member of AES Boston can purchase ARC for their studio at the cross-grade price ($449 instead of $599) and also get a free copy of T-RackS EQ, their tube modeled 6-band EQ. Orders will be handled by Parson's Audio, who helped arrange the demonstration. Parson's phone number is 781 431 8708.