X-curve plug-in options?

[dr sound]

Andre,
I agree to most of what you've posted above. I am very aware of what the "Music industry" is and was. For Feature work one must understand all aspects of the delivery and mixing of such set standard. I can tell that your roots are in Music. I know many very talented Music guys who have made a career in Post Sound. I have also seen many a guy walk in with an attitude and a lack of knowledge. I am not saying you have you have an attitude, just a lack of knowledge. I appreciate your desire to open up to other aspects of mixing. I support spreading knowledge or otherwise I wouldn't post as much as I have done. You can see by my past post and also the "Room Calibration for Film and TV" sticky that i try to help! I am far too busy to post as much as I have in the past.
As to PT LE and...., I think everyone knows where I stand on that one!
Good Luck in your quest,

[Sound Guy Andy]

Just to try to explain a bit more about the room EQ...

Branko, thanks for your input...this is good stuff. I knew that the X-Curve had to do with reverberated sound affecting the dry signal, but I hadn't made the [obvious] connection that that's why our smaller room doesn't need this sort of compensation.

Still, it's somewhat surprising there's no plug-in that's tailored for this very feature; after all, just about every other surround-related process has gone "soft."


Andre

[Sound Guy Andy]

Andre,
I agree to most of what you've posted above. I am very aware of what the "Music industry" is and was. For Feature work one must understand all aspects of the delivery and mixing of such set standard. I can tell that your roots are in Music. I know many very talented Music guys who have made a career in Post Sound. I have also seen many a guy walk in with an attitude and a lack of knowledge. I am not saying you have you have an attitude, just a lack of knowledge.

I agree, when it comes to film mixing. Fortunately my partner has a strong background in this field, so together I think we make a strong, capable team.

I appreciate your desire to open up to other aspects of mixing. I support spreading knowledge or otherwise I wouldn't post as much as I have done. You can see by my past post and also the "Room Calibration for Film and TV" sticky that i try to help! I am far too busy to post as much as I have in the past.

You've already been a great help (as have others), and you'd be one of the people I'd refer a client to if a job were too big for our britches.

As to PT LE and...., I think everyone knows where I stand on that one!

Yeah, I'm glad we sprung for the real TDM deal...I wouldn't want to think about faking all the busing needed for surround in an LE system (not to mention the other drawbacks).

Good Luck in your quest,

Thanks! I hope this isn't the end of your contributions!


Andre

[Branko]

Still, it's somewhat surprising there's no plug-in that's tailored for this very feature; after all, just about every other surround-related process has gone "soft."

No, it's not surprising! A simple 1/3 oct eq becomes a "x-curve calibration tool" only in conjunction with a 1/3 octave RTA, properly built room, adequate monitors and a trained Dolby Consultant. I doubt any plug-in manufacturer would risk it's reputation by offering an EQ plugin as a "X-curve EQ" and receiving complaints like: " I used your plugin to set-up my room, mixed a feature in it and it sounded like s**t in the theatre"!
There are some excellent analyzer plugins and stand-alone softwares on the market, but for a good RTA, you'll need a flat omni mike, a good preamp... see what I mean?
Branko

[Sound Guy Andy]

Blanko: No, it's not surprising! A simple 1/3 oct eq becomes a "x-curve calibration tool" only in conjunction with a 1/3 octave RTA, properly built room, adequate monitors and a trained Dolby Consultant.

That's true, but the EQ itself could be used after the initial calibration is done with the other tools, and then a hardware EQ box wouldn't be required; this is how the Waves Surround Bundle works.

Blanko: I doubt any plug-in manufacturer would risk it's reputation by offering an EQ plugin as a "X-curve EQ" and receiving complaints like: " I used your plugin to set-up my room, mixed a feature in it and it sounded like s**t in the theatre"!

This would be no more of a risk than their current position, in which any of their tools could be mis-used to the detriment of their reputation...we've all heard the Waves C4 (and some hardware boxes like the TC Finalizer, for that matter) get a bad rap for oversquashing source material thanks to misuse, but those "in the know" attribute it operator error and keep supporting their products.

Besides, it wouldn't have to be marketed as a niche product; any EQ plug developer could just add a 1/3 oct option to their current lineup and call it an "upgrade."


Andre

[Eric L]

What are the deficiencies of my current setup? What would a more ideal setup be? Since you've read my other related post you know I'm doing calibration/bass management in software, so that's not a concern.

1. You are trying to fill 3300 cubic feet of space with nearfields that have 4 inch cones.
2. Your speakers are not behind a perf screen like in a theatre
3.You watching video playback on a 19 in LCD monitor with all the inherent delay that comes with that. How do you or your clients see lipsync?

These are only the obvious limitations your set up has for theatrical work.

[Sound Guy Andy]

Eric L:
1. You are trying to fill 3300 cubic feet of space with nearfields that have 4 inch cones.

It's not quite that much space due to some weirdness in the room's layout (which is not ideal either), but in any case, is there a common speaker size (or RMS rating)/room volume ratio?

2. Your speakers are not behind a perf screen like in a theatre

Can this be accounted for with a slight reduction in the highs in the monitoring chain?

3.You watching video playback on a 19 in LCD monitor with all the inherent delay that comes with that. How do you or your clients see lipsync?

I've been using imported quicktime files instead of locking to a deck, so I'm able to account for LCD delay and there's no realtime Firewire (or analog video conversion) delay.

These are only the obvious limitations your set up has for theatrical work.

Are there some less obvious ones I should be aware of?


Thanks,
Andre

[dcaudio]

If I can take the liberty to morph the original question into, "Are there any plugins that can do 'room eq,' I can answer it a little. And then I will add my extra 3 cents for the sake of a good argument. Any EQ plugin on master outputs can change your monitoring chain calibration (kinda). For instance, if you had a room/speaker anomaly that always made you hear +8dB from flat between 80 and 100Hz then you could put any EQ with a -8dB response in your monitoring chain. Then you would hear your mixes flatter and your mixes may sound better and translate to other listening environments. The EQ could be a digi EQ, a 10 band waves EQ, or there are some 31 band graphic EQ's out there I believe.

But, imagine this:

You are mixing a production dialouge track that was wonderfully recorded with a spectacular voice and it needed no processing before you started your mix, nor after. If you ran it through PT and did not turn a knob, but your master EQ took out 8dB at 80-100hz then that dialouge track would be brittle and have a lack of low freq. BUT, it would SOUND flat in your room. It would sound good to you but not in another space.

So what I would suggest for a "soft" calibration EQ would be signal chain like this:

Master busses split to 2 places: ONE-- your mix down device (or busses that are bounced to disk); TWO--to aux inputs with your room EQ inserted and the output routed only to your speakers.

Live music mixers do this type of thing all the time. They record a board mix that is the master Stereo buss directly. At the same time they send that same mix out another Stereo output and send that through a 31 band graphic EQ, a parametric EQ, or a combination thereof. They spend a few minutes (or a few hours) calibrating the system in a number of ways:

1. They might listen to a CD of which they know sounds good to them on most playback systems. Then they tweak the EQ till it sounds good to them. Much like a visiting mixing engineer might attune his own ears in the host studio by putting on the Frampton Lives CD that he annoys the dog with at home every Tuesday night. He knows that in his living room (and a bunch of other listening environments) the kick in verse 3 hits him lightly in the left breast at just the right volume. He also knows that the cymbal crashes in the outro tend to hurt a bit and cause him to bite his lip. He adjusts the EQ so that these things happen.

2. They might play some pink noise and look at an RTA. The RTA has as its input a mic that sits at a few places in the room. If 200hz is always sticking up then they might pull it down with the EQ. They can adjust the EQ until the RTA looks flat (or flat until 2Khz and then rolling off at 3 dB per octave.

3. They might use an automatic EQ device such as DBX's DriveRack PA with its Auto EQ process. It puts out pink noise listens with an attached mic and automatically adjusts the EQ so that the pink noise seems good to that algorithm.

4. They might talk into a mic that they know well. They have heard there voice thru say an SM58 a thousand times. They adjust the EQ so that their voice sounds like they remember.

5. They could wait until the band starts playing and people have filled the room and the temperature and humidity has risen and the band is playing louder and THEN adjust the EQ just to taste.

6. They may use some fancy computer app and do a transfer function that takes into account the time domain (ie phase) and adjust to some degree of flatness.

I believe all of these techniques can apply to all forms of audio system calibration. Live sound, film sound, TV sound, music sound, live theatre, game sound, drive thru restarant sound, and even NASA communications to and from its astronauts (well maybe not) can benefit from using some or all of the techniques. The trick is how much should we EQ our systems so that the mixes done there sound right in the spaces intended for their reproduction.

Most people I trust say that room acoustics and monitor placement are a better place to start messing with things to make mixes translate. But if you are not going to do that, most likely for $ reasons, then I believe that theoretically a soft EQ plugin could be useful. Try to make it sound good with all kinds of music playback and film DVD's by adjusting using your ears and intuition. Use a program like Spectrafoo or SIA SMAART or something that can do a transfer function. Use a small omni mic that has flat specs. At your listening position pink noise should look flat until 2k then rolling off at somewhere between 3 and 1 dB per octave.

Does someone have a PDF of iso 2969?

Remember that almost all plugin EQ's (except maybe some linear phase waves thingie) introduce phase changes when applying EQ, This might be detrimental and somewhat counterproductive to just leaving it flat. I think the risk is worth it most of the time.

Also as you apply corrective EQ to your monitor chain you might want to put a reverb plugin inline also. Then you can mimic a larger room that your mixes might play in. One of the most interesting things to me is that there is a psychological effect that “tunes” a listener’s ears differently depending on the size of the room/screen. I believe that assumption is the best reason for the X curve.


Below are some quotes from:


http://www.sdinfo.com/volume_9_2/fea...es-6-2002.html

and
http://www.robertmargouleff.com/publ...ound_0100b.htm
and a JBL technote.



“Also, when heard over a modern flat loudspeaker in a small room, program material balanced on an X curve monitor sounds overly bright”

“Or in simpler phrase, we perceive sound in a large room to have more treble.”

“Small, deader rooms need less and less of the full X-curve compensation, as they have less of the meter-confusing reverb present.”


“For almost 30 years, the X-Curve has provided the motion picture industry with a valuable standard that ensures plausible interchangeability of program material, from one studio to the next, from studio to theater, and from film to film, which takes into account the different perceived spectral response of different room sizes.


Maybe one vision for the "Room Type" flag was to one day trigger "large room simulation" DSP programs to help recapture the large room experience, more like what was heard by the mixer.”


From JBL Technote concerning Studio Monitors for Multichannel Sound Apps:
http://www.jblpro.com/pub/technote/tn_v3n03.pdf


(I think the part about the screen introducing high Freq loss is misleading....Wasn't the room calibration done with the screen in place?)

“Another important step in correlating the small
room listening experience with the standard cinema
is overall signal equalization. The cinema and
dubbing theater are normally equalized to the
ISO 2969 curve, shown in Figure 5a. Also shown
here is the typical on-axis high frequency loss
caused by the film screen at Figure 5b. When a
film is brought into a video mastering studio, it will
sound quite bright, inasmuch as there is no
screen loss function to match the sound to that
which the film mixers heard. This must be compensated
for in the processing of film product for
home video tape, Laserdisc, or for Video DVD.
The final EQ must take into account the fact that
high quality home loudspeaker systems are now
being designed for fairly flat on-axis response out
to 8 or 10 kHz. JBL’s suggested guidelines for a
target surround loudspeaker room EQ are shown
in Figure 5c. This equalization is empirical and
represents an average of consumer installations
in which low frequencies may be slightly boosted
by diminished sound absorption at low frequencies
and rolled off high frequency response due
to increased sound absorption at high frequencies.
Therefore, the mixing engineer must re-equalize
all film channels to compensate for screen
effects as well as the basic difference between
the ISO 2969 curve and the normal conditions
home listening. For the most part, this has
done “by ear,” but THX has outlined a rational
approach to carrying out the entire film-to-consumer
equalization chain.”


And to finish this lengthy diatribe I will say that nothing beats checking your mix in the space it will play in. And barring that, a room with similar acoustic and screen size and room size. And barring that, a dub stage. And farther down the line is a smaller room with some plugins to compensate for being so small. And furthermore, this list is purely to try to emulate how someone else will hear your mix. If you want to get creative and use that part of your brain, I believe monitoring on nearfields or even in headphones can let you hear some details that your would not consciously hear on a dub stage of grand proportions. These details might even translate subconsciously to a listener in a theatre.

Cheerio,
Ryan

[Eric L]

1. You are trying to fill 3300 cubic feet of space with nearfields that have 4 inch cones.

It's not quite that much space due to some weirdness in the room's layout (which is not ideal either), but in any case, is there a common speaker size (or RMS rating)/room volume ratio?

No there is not. Lets chalk it up to experiences...your speakers are too small and thus you will be too close to them.

2. Your speakers are not behind a perf screen like in a theatre

Can this be accounted for with a slight reduction in the highs in the monitoring chain?

No it can not. Not accurately nor predictably, at least.

3.You watching video playback on a 19 in LCD monitor with all the inherent delay that comes with that. How do you or your clients see lipsync?

I've been using imported quicktime files instead of locking to a deck, so I'm able to account for LCD delay and there's no realtime Firewire (or analog video conversion) delay.

That's fine, but what are you clients watching? The 19" over your shoulder?

These are only the obvious limitations your set up has for theatrical work.

Are there some less obvious ones I should be aware of?

I'm not sure of the less obvious ones, because I can only make assumptions based on the info you share about the "obvious" ones.


Thanks,
Andre

[/QUOTE]

[dr sound]

dcaudio (Ryan),
I just wanted to thank you for an EXCELLENT post! Very well said!