[cyrano]

Surround isn't Ambisonics, Serr.

Surround is created in the mix, mostly.

Even if they use a soundfield mic sometimes, they still mix in other stuff, from mono or stereo sources. That can work for surround, if done carefully. But there are some uncertainties involved. Like "where should the actor's voices go?". It's very simple for a documentary. The narrator's voice is mono and goes to the center, and, maybe, attenuated to the front speakers. An interview, with the interviewer to the right and the interviewee to the left, should be slightly panned accordingly. But what with actors who move around, or off screen? Only a few movie productions have tried to pan actor's voices in the 2D space. The vast majority make it simple mono, through the center channel, or narrow stereo. And the results are not always easy to reproduce nicely, even in a movie theatre with THX calibration.

Because of all this, the soundfield is lost. You can no longer apply the math to calibrate the speakers. It' all guess work. That's why the effect is often lost in the living room and even in the carefully setup home theatre.

True ambisonic recording starts and ends with the soundfield mic. Easy for "natural" sounds. Doable for classical music. Not so easy when recording a band, as you will be recording the PA, maybe some monitoring and a lot of unnatural room reflections. There's no soundfield in it. Nothing to be "extracted" later. You could compare it to M/S recording. That needs to be set up carefully too.

I've been experimenting with it. It's awfully hard to create a surround mix with natural sounding music from a multitrack recording. And afaik it's impossible to create a real soundfield, which is needed for ambisonics.

So I took down the 7.1 setup I was slowly building as it's useless for ambisonics and went back to a 4 speaker 2D setup. At the moment, I'm trying to figure out what is the best way to go 3D and how many speakers are really needed.

I'm a big movie fan and have quite a collection of DVD's. Some of them have nice surround sound. Some recent productions have quite messy surround sound.

But I've also been collecting 5.1 music mixes, mostly from the net. Just for test purposes really. And these are mostly awful. I don't like them at all, as they seem to be based off the original multitracks, mixed to 5.1 in a hurry in some cases. Sometimes, they're even just a surround effect added to the stereo master.

Could be me, could be my setup. But my setup seems to work for most movies. I would welcome what others have experienced, but I'm afraid not too many people listen on a 5.1 capable system and even less are really interested.

That's why ambisonics seem like a welcome addition to the array of recording tools. On the enduser's side, setup can be done (in the future) by the reproduction system. And it works on headphones, while surround really doesn't work on these. But even on the recordist's side, it's quite simple.

I'm planning to build my own tetrahedral mic. I've experimented with 4 Behringer B5's in a tetra setup a bit, but reached the conclusion I really need 4 good preamps. My FF400 only has two and the 4 channel Tascam i have doesn't cut it. So I'm awaiting the delivery of an extra pair of preamps (Core Sound Mic2496) to see if that'll work. If not, I'll continue the search for an RME QuadMic...

All of this experimentation isn't professional, of course. It's just playing around, trying to grok the system. And the system holds a lot of promises for me.