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Octophonic + subwoofer approach

Hello!

I’m use an octophonic system (8x Genelec 8020b), for a piece with trombone, live electronics and interactive spatialisation (iPhone strapped to trombone sending compass values to control several sources’ azimuth). I’m using Spat 4.8 on Max 7.3.4 on a MBP.

The sounds are quite bass heavy, and possibly too much for the small Genelecs, so I’d like to add a subwoofer (we have Genelec 7050b) onto the system.

My question is: what would be a good way to mix down the 8 channel output into an extra 2 outputs to feed the subwoofer (accepting stereo in)? Also, is there a way within spat to output some channels (e.g. 1-8) with less bass and focus the lower frequencies onto say the sub channels (e.g 9-10)? Unfortauntely I don’t have the hardware to do this the normal way (i.e. routing the channels through the sub, because the sub only has 4 channel inputs).

Previously I’ve just sent channels 1-4 into 9 and 5-8 into 10 of the dac~, then from my Motu interface, channels 9-10 into the subwoofer. But I’m wondering if there’s a better approach, since I’m still new to spat…

Many thanks for any thoughts!
NM

Hi,

Well Panoramix might be the right handy tool http://forumnet.ircam.fr/product/panoramix-en/

Hello NM

I have tried this approach using max msp:

Add all the speaker outputs from the spat.spat~ object together so they are one channel. Put a gain control on this channel and send it out one of your sound card outs to the sub LFE input. Be careful to turn up the gain slowly.

You will of course also have the outs from spat.spat~ going to the speakers themselves like normal

See pictures attached

Good luck

Screen-Shot-2018-05-02-at-10.47.00.png

Thanks to both!

Panoramix looks like a good long term solution (post-Max/pre-soundcard), but for now I’ve made something in Max based on mrtea’s idea (thanks for the photos!).

Cheers!