I was kindly invited by Andy Moore, the product manager of Arcam to spend the day at their HQ in Waterbeach, Cambridge. The whole day was spent in a windowless demonstration/test room playing with the latest AVR850 receiver. It was just the kind of thing i love to do!
Arcam have incorporated Dirac Live into some of their stereo and surround amplifiers. A powerful room correction 'EQ' system that enhances the already excellent sound of their products.
Dirac measures and then seeks to correct not only the frequency response of each loudspeaker's behaviour, but to improve the impulse response too.
We discussed the behaviour of audio in typical home cinema rooms, the pros and cons of EQ and best practises to get the best results. Unlike some other EQ solutions out there, Dirac gives you the ability to choose the final 'curve' that you'd like to hear. Normally, other systems can give you a great sounding result, but there's rarely a facility to tweak the sound the way that you like it. Therefore you are at there mercy of what the AVR manufacturer has chosen to be a 'good sound', or 'EQ curve'.
For example, on a basic Denon home cinema amplifier, once you have run the Odyssey EQ, you then have choices wether to apply the EQ to all or some speakers. Or, to use Odyssey to help flatten the speaker response or fully EQ the speakers. I think this is great, but it's nice to see even more flexibility available now.
Dirac Live with Arcam goes the extra mile so that you can adjust areas of the sound spectrum by just 1db up or down for example. This might be ideal if you like a more 'sparkly' sound by boosting the treble region slightly. Or adjusting the bass region higher if you like to shake the walls more. Consequently it will then also adjust the impulse response correction in line with your minor or major EQ change.
The option to customise the curve isn't just to taylor to your own taste. It's also an opportunity to choose just how much you want the software to 'force' a corrected sound across your system. Corrected dips in the sound, i.e a room node drop at150Hz, can't truly be fixed by adding forced correction. Therefore you can study the reading on the screen and choose to fully or just partly attempt to correct this dip.
In practise, it takes some time to run the process correctly. Each of the 12 (Dolby Atmos arranged) speakers are measured from 9 different test microphone positions.
This way, a clear representation of the room and speaker's acoustic behaviour is built up. Prior to this of course, we are running audio tests as a reference for comparison.
After the measurements are taken, the results are processed very quickly and remotely (via the network to Dirac HQ in Sweden) and received back ready to be applied. Our laptop uploads the file to the AVR850 and we're ready to listen.
I'm not a great fan of EQ for stereo systems, it's hard to find something that doesn't mask the signal/music. For rooms filled with speakers, like home cinemas then it really tips the balance for me in favour of EQ. With so many speakers firing here and there, then something to tame the room response is required for most systems.
Dirac Live brought the whole sound together, tightened the bass response, the imaging too. The most amazing effect was how it seemed to take the walls disappear (audio wise!). Therefore the soundstage took on the feeling of a much larger room. Probably like the large sound studio that the movie soundtrack was mixed in. It was clearly better and easier to follow everything happening in the sound mix, the room came alive!
There really is a a lot more to say about the set up process and the results of the day at Arcam with Andy.