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

[Fernando Lopez-Lezcano]

On Tue, 2010-08-03 at 20:17 +0200, Jörn Nettingsmeier wrote:
> On 08/03/2010 07:45 PM, Fernando Lopez-Lezcano wrote:
> >
> > Hmmm, so, you send WXYZ to the four subs and whatever order you can
> > decode to the regular speakers (6, 8, etc). Sounds good.
> 
> it does :) except you'd usually throw away z, 

Yes, of course, that was my mistake - I don't have subs in the ceiling
or floor (yet :-)

> > 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?
> 
> hmm, i think i would rely on the internal electronics of the tops for 
> the HPF and feed them a full-range signal of all components, and then 
> maybe measure one and design a suitable roll-off for the bass 
> speakers... but i have never had the luxury to do that, i always set the 
> LPF by ear.

I currently have 8 Mackie 824's at ear level, 4 624's in the ceiling and
4 624's below the floor (and I will add two more 624's, one zenith, one
nadir). So their frequency responses don't exactly match in the low
end. 

Right now I'm writing a software crossover with HPF / LPF sc ugens
(12dB/oct butterworths). 

> sending high-passed WXYZ and full-range higher orders to the tops won't 
> work well, i guess. if you want to take care of the band-splitting in 
> your mixer, your best bet would be ganged high/low-pass filters for all 
> the orders. 

That is what I'm currently trying. I still don't have a clear idea of
what would be best - or even reasonable - in terms of high order
components (at this point in time I only have 2 subs so I'm sending them
just W, but the code supports 4 and I plan to have that setup soon, at
least for testing). Fons?

-- Fernando