SPL Atmos 5.1 system

[huub]

Ah yes,
It was a DJ Tiesto gig, the best dj in the world apparently, whatever

The guy who will be mixing the dvd, barney broomer, wanted to us the atmos,
it was rigged in a lighting truss:
http://www.gearslutz.com/board/attac...n-p1000228.jpg
Here you see it in action:

http://www.gearslutz.com/board/attac...n-p1000265.jpg
In addition to the atmos, we put up our usual senn 416/ neuman km140 combi,
from the stage, aimed at the audience (obviously ).. 4 416's and 2 km140's

The spl from the PA was insaaaaane, and the sub HUUUGE, but both our own mics (neumans at -10 pad) and the atmos held up fine..

I made a little temp stereo mix, and monitored in surround, curious to hear the atmos..

I have to say the atmos wouldn't have been my choice, for pop I prefer to make stereo and surround ambience as huge as possible, and I'm not interested in realism (I very rarely do classical, and gladly leave that to the specialists).
Also, the front three mics were aimed squarely at the main PA stack, and thus captured the pa mix, they did this in high quality though, , it sounded like a pa l/r instead of coming through mics..

However, at crowd -only moments (just cheers, no pa) the atmos sounded really huge and clean and clear.. I think the position (couple of meters above the crowd, see pics)
was perfect..

All in all, lovely mic, good choice for this dvd, but I personally would be fine with mics at the stage for front (a couple really high above the stage too preferably),
and a bunch (well, two is fine, but a couple of flavours of mics, for flexibility during mixdown is nice) of mics at foh or about there position for rear ambi.

For a dvd I mixed last month, I had 2 km140's for surround ambi, and two dpa 4006's, in the end I only used the two 140's (aimed at crowd from back of room) and loooved the result..

So, there you have it...thumbsup

[Martin Kantola]

Originally Posted by Roland

You are displaying a fig of 8 response from a mono (dual capsule) microphone. Couple with this that it is a classic Neumann and you would expect it to have good characteristics (this is why Neumanns have there reputation). I'm sure that it is significantly smoothed and if you look at responses such as cardioid and omni it doesn't hold up so well, but then other mic's don't either. Now add into the equation that this is a mono mic and it's response would be different if taken as part of an array.

But we were specifically talking about a good microphone setup for Blumlein, not? That takes two simple fig-8's, one for each channel. No array, no matrix.

I agree totally with Plush's asessment of the Soundfield, as a single point surround, solution it is the best out there without a doubt.

Now THAT I can easily agree with! Don't feel it's the best solution for a simple Blumlein necessarily, and the reason I participed in the discussion is that I'm wondering if these high frequency problems might have something do to with the lack of the even bigger success for the Soundfield.

Best,

Martin
PS. Sorry for partially hijacking the thread...

[Roland]

Originally Posted by Martin Kantola

But we were specifically talking about a good microphone setup for Blumlein, not? That takes two simple fig-8's, one for each channel. No array, no matrix.
Best,

Martin
PS. Sorry for partially hijacking the thread...

Well I was discussing it mainly in view of the fact the thread is about 5.1 surround, trying to record surround with the various systems available (and there are a few more these days) all have some form of compromise, not unlike electronic design, but as a very good electronic designer I know well told me "it's a case of balancing and trading off the compromises for the best overall effect". Blumlein techniques have their uses, however they are also are not seen as the holy grail or we would all be using them all of the time. Surround has opened up a whole can of worms and where as it is wonderful to work with it comes with it's own drawbacks and few systems offer reliable, repeatable, workable solutions. In ideal and specific situations many solutions may work, where the soundfield scores is that it is possibly the only system that can satisfy this criteria. If Blumlein is your thing, hand set-up pairs may well be the way to go, however even here the Soundfield will give a more than acceptable result (plus remember its post options, assuming you record the B format signal). I have only one problem with the soundfield in that I have always used other peoples and reading this thread back I realise I should own one.

Regards


Roland

[Plush]

Hello Martin,

I think you're worrying too much about the difference between a smoothed laboratory (or even marketing department) brochure and the real world performance of the mic.

The U89 is a great mic and one of my faves. In my opinion, the graph you posted is an advertisement instead of a bible.

Angelo Farina's graphs are real world lab measurements, apparently unsmoothed, and I can tell you that the Neumann one would look similar at 16K. The rules of physics dictate it.

Yesterday I used our Soundfield for a recorder, h-chord, bassoon and oboe ensemble.
The sound was mindblowing and holographic.

Why debate design when you can listen and be amazed?

[Martin Kantola]

Originally Posted by Plush

Angelo Farina's graphs are real world lab measurements, apparently unsmoothed, and I can tell you that the Neumann one would look similar at 16K. The rules of physics dictate it.

Well, no. I thought you claimed earlier it was a broken mike he measured? Been dealing with actual microphone polar pattern measurements enough to know roughly what to expect from a typical dual-diaphragm capsule. And a real fig-8, a ribbon, looks pretty good too. Even before any smoothing.

But if you still insist the high frequency polar response of the Soundfield is as good as any other mike, that's fine with me. But don't expect me to agree with you. Did you ever read the Gerzon paper I mentioned?

Why debate design when you can listen and be amazed?

How true. I do listen a lot, believe me. Theory and measurements only makes sense if they correspond to real-life listening experiences. After all, microphones are to be listened to, not measured...

Martin

[Plush]

It is my contention that the high freq. response of the Soundfield is typical of a high quality condensor mic. You can hear that it is proper. That is my point.

( I inferred that we don't know exactly what we are looking at with Farina's graphs since, by his own admission, some of his Soundfield mics needed repair)

My contention that Neumann's graphs would look similar to Farina's is true when comparing like with like. I have seen the raw measurements out of the Neumann Berlin lab and that is the reason I state my belief.

In any case, I'm a recording guy and tape jockey who is also a recording scientist.
Discussion is beneficial for many reasons and one of them is that sometimes a myth can be dispelled.

My primary interest is in recreation of a musical event with a nice tonal quality and high pleasant-ness quotient. Sometimes the Soundfield mic (especially in an excellent acoustic) is just the right tool for reaching for my goal. Perhaps only 10-15% of my own work is using any Blumlein arrays.

[Martin Kantola]

"However, the Soundfield system has the advantage of being as perfectly phase coherent as any Blumlein can be."

The above is your statement, but where is your proof? Do you have polar plots of Soundfield microphones? Please show us something. Time to put the myth to the test...

This is an interesting discussion indeed.

Martin

[Plush]

I see that several are not convinced by my descriptions and assertions. That is OK because far greater minds have already proved that the Soundfield is THE MOST phase accurate system available.

The maths done by Gerzon prove it, the 30 years research and testing of the Soundfield by the BBC prove it and the proved and accepted theorems of B format prove it.

Indeed, mere listening proves it.

The whole system is designed to offer the most phase accurate pick-up available. Since when do the doubters believe that a microphone polar plot tells the whole story?

Please consult the manufacturer with your demands for proof. I am merely a tape jockey and user of the [marvelous] product.

Raise your rates so that you can get one!

[Martin Kantola]

Originally Posted by Plush

The maths done by Gerzon prove it, the 30 years research and testing of the Soundfield by the BBC prove it and the proved and accepted theorems of B format prove it.

Oh, you must mean this:



Martin

[Plush]

I have read your reference above and you and Gerzon are absolutely right. The microphone requires equalization to maintain a good polar plot. While they're inside the mic electronics working at that goal, why not use equalization to make the mic have excellent phase response too.

I said both of those things early in my posting history here on this thread.
It was my pleasure and treat to discuss these things with Gerzon and learn from him on many separate occasions.

What exactly is your beef with this design or its implementation? Or do you just not like my boosterism?

It's just a tool.

[Martin Kantola]

Plush,

think we're talking about two different things, you are focused on the electronically corrected responses BELOW the "limiting frequency" while I'm concerned about the "contaminated" response ABOVE this frequency.

A typical dual-diaphragm capsule or ribbon does not have these problems, therefore it still works better for a pure Blumlein setup IMHO. Especially if we are talking phase responses. The electronic filtering does not completely fix all the issues. Might even introduce a couple of new ones.

Also, I have reason to believe that this specific issue can be heard in the Soundfield design, but that does not make it a bad microphone necessarily

Hope this answers your questions.

Martin

[Plush]

NONSENSE.

The equalization applied is applied precisely to overcome the so called "contamination" above the limiting frequency. The EQ does not just stop at 7 or 8 K.

I think that I have said all that I want to say here on this thread. I usually refrain from endless back and forth postings.

[Martin Kantola]

"The microphones are effectively coincident up to about 7 kHz and are subjectively well behaved above that." -Gerzon