[LAD] what does "full range" mean with regard to ambisonics and speakers?

[Bearcat M. Şandor]

On Tue, 2010-08-03 at 10:45 -0700, Fernando Lopez-Lezcano wrote:
> On Sun, 2010-08-01 at 13:39 +0200, Jörn Nettingsmeier wrote:
> > On 07/31/2010 11:14 PM, "Bearcat M. Şandor" wrote:
> > > I am planning on subs that have their own low-pass filters. I have a
> > > pair of Anthony Gallo Reference 3.1s but for this ambisonics set up, i'd
> > > get 4 pairs of the Anthony Gallo Stradas and 4 T3 subs.  stradas:
> > > http://www.roundsound.com/reference-strada.htm  t3:
> > > http://www.roundsound.com/tr-3-subwoofers.htm  Most of the stuff on
> > > those pages is marketing of course, but the satellites have a range of
> > > 45 Hz - 20 Khz +- 3 db and the subs go down to 22 Hz (no variance given).
> > >
> > > That push-pull idea sounds fantastic. I would love it if you'd show me
> > > how to create a set up for a system like that using ambdec, if you have
> > > the inclination and the time. That's what i was planning on using anyhow.
> > 
> > basically, you take fons' example for the octagon, set the speakers up 
> > at the correct angles and then enter the actual distances into the 
> > matrix, so that delay and near-field compensation is correct for your 
> > setup. then you take the example square for the subs, set them into the 
> > corners of the room and again enter the correct distances.
> > 
> > at this point you have two ambdec instances running, one for the tops, 
> > one for the subs. you'd need to adjust the relative loudness with 
> > ambdec's faders. once you've determined the correct relative levels, you 
> > can factor them into the matrix coefficients of the sub decoder and run 
> > both ambdecs at 0dB. now you can hack both matrices into one and end up 
> > with a 12 channel ambdec configuration: 8 tops and four subs. easier to 
> > start up in daily use.
> 
> Hmmm, so, you send WXYZ to the four subs and whatever order you can
> decode to the regular speakers (6, 8, etc). Sounds good. 
> 
> What if you want to include a crossover? (that's exactly what I'm
> working on right now in the openmixer software). 
> 
> So, you high pass WXYZ and send that to the regular speakers, low pass
> WXYZ and send that to the subs... and what do you do with the rest of
> the Ambisonics components? I imagine I would just send the full
> frequency range to the regular speakers and let them do the best they
> can, right?
> 
> -- Fernando
> 
Perhpas i missed something further down in this discussion, but what
would be the deficit to letting an outboard crossover (like the ones in
the subs) handle the passing vlf instead of setting up ambdec to do it?