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Forum Index » Profile for chrisatrational » Messages posted by chrisatrational
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StudioLive General Discussion » Save EQ after SMAART Room Analysis? » Go to message
Hello Switch - After going over this thread, it sounds like your whole issue is with the deploy ability of placing filters and the speed at which you can make adjustments. I'm realizing that your issue has more to do with how the console is laid out than the whole topic of PEQ's, GEQ's, or system tuning in general. The GEQ's are not a good on the fly eq with the 16.4.2 surface because of how you access them, especially compared with how easy it is to use the fat channel.

Have you tried controlling the console with an iPad? It's really quite quick to get to the GEQ's from that, making on the fly adjustments possible. If you aren't using your console this way, and without any outboard gear as well, the user experience of getting to the GEQ's quickly is a bit of a buzz kill.


PS. As for phase distortion issues with GEQs, that's mainly user error. When the controls are all over the place then you know that you're in trouble. It doesn't have to be that way.


Any amount of eq introduces an amount of delay to the signal, it's not really something you can get around. Also, these distortion issues are often desired - ie analog circuit emulations. The difference between the characteristics of the smear are what makes one eq more musical then the other. A Parametric Eq will have a smoother response then a Graphic, whose response will be more jagged - as you would expect.

Cheers!

- C
StudioLive General Discussion » Save EQ after SMAART Room Analysis? » Go to message
Switch - Exactly, that's why I said it really doesn't matter how you go about getting your results We are just encouraging a workflow that is helpful and in-line with today's professional standards. There is nothing wrong with using the techniques of the 'top-flight' pros at any level. It is my opinion that aspiring to work like your favorite engineers, no matter what level of shows you are doing, would be something to strive for.

Because the Geq algorithms are the way they are on SL's, the traditional rules don't apply as they would with other gear, you and I both know this. I am merely encouraging folks to work through the process methodically - not just reach for the Geq because it is what is comfortable or familiar.

You, as well as other folks, bring up the lack of fully adjustable Q on the 16.4.2, "who cares" I say. With the right adjustments there is nothing you can't achieve to satisfactory results with it being the way it is - and then you still get a flat Geq to adjust during the show - seems ideal to me!
StudioLive General Discussion » Save EQ after SMAART Room Analysis? » Go to message

In the SL signal flow the PEQs come before the GEQs, so a PEQ room correction curve will also warp the Smaart RTA graph. Even after room correction that graph won't represent what the audience is experiencing. Also, the PEQ room corrections will be in your headphones too but the GEQ to taste corrections won't. That should be the other way around.


Switchback - Great Insight, you have done some serious brain crunching over this, and that is fantastic!! There are definitely caveats to the way that the wizard is integrated into the SL console, as it was done a few years after dev of the original design. The RTA graph is not a 'tell all be all' representation of what the audience is experiencing, and shouldn't be considered as such. What it does excel at is verifying what you are hearing with your ears. For example, you hear feedback, and think it's around 1khz, you can look at an RTA and see at exactly which frequency the feedback is occurring at. Or, if you think your mix is boomy, you can look at an RTA and hone in at which frequency it is most boomy at etc. The RTA is relative and should be treated that way. You don't want to pigeon hole yourself into 'but it's looks great on the RTA, why does it sound like p**p?!'. The RTA is a reference tool, not a reference standard.

If you are running your main L/R off of the Main L/R fader, then yes, the eq on the main fader will be in the headphones as well. This is unfortunate that the headphone isn't on a separate buss as you and I expected. I've adopted a workflow where I run L/R off of sub groups 3-4. Not only do I desire to have a 'untouched' headphone mix, I also like to have control over L/R separately and tune them both as separate systems. This is of course a bit more complicated and also requires sacrificing 2 subgroups, so it may not be something that the majority of users are into. Again, this is a caveat, and knowledge is power. Now that you know, you have the power to adopt a work flow change, or otherwise accommodate for the design.


I appreciate that the PEQs may sound better, and that suggests that the GEQs should not be used at all. But from experience I know that GEQs sound just fine as long as you don't try to do anything extreme.


The geq's in the SL boards are unlike tradition geq's, if you haven't read the section on them in the user manual for the 24.4.2 I highly recommend you do - presuming you have, I'll say this: You can use whatever Eq you wish to for your show, no one will scold you and if it works it works. However, what we are trying to do is encourage a work flow that is used by the most top-flight of audio engineers. That you tune your system with a parametric Eq for the show/venue you are playing on that particular gig - this way you can have the GEQ for eq decisions during a specific 'act' while they are performing, and then be able to return to 'flat' by zeroing out the Geq after they are done for the next band/engineer/operator to work with a freshly set table, not one with the dirty dishes left on it.

The argument of whether Geq's 'sound fine' or not is a moot point. the fact is, GEQ's are fixed frequency, fixed bandwidth. There is absolutely no way to set a Geq to a -7 dB 1/3 octave wide filter at 700Hz without tediously adjusting multiple adjacent parameters while viewing the result with an electronic measurement - and even then you will never get it as ideal, or as quickly for that matter, as could be done with one -7 dB 1/3 octave filter at 700Hz.

And isn't that the whole point with room correction anyway?: Don't pull every trick available to make it dead flat in one point in space but apply a smooth correction for a more balanced sound on average. The GEQs should be able to do that job just fine


You are right on! The goal is to create a frequency response for your sound systems in order to generate a better overall sound throughout the average area of the listening environment. Typically this can be done with one, or two, well placed filters! So, while the GEQ's can do the job to a degree, they are better suited for other purposes, as the most elegant solution for system tuning is the PEQ.

I hope this helps

Edit: FYI 'Flat' does not mean a straight line across the frequency response of a system. Flat, as a starting point when talking about live sound system tuning, is an exaggerated Sub range (below 100Hz if subs are in place), relatively flat form 200hz to 2Khz, with a gradual drop off after 2kHz.
AudioBox VSL 22 » What is the best sound quality and the use of this AudioBox VSL 22 or Roland UA-55 » Go to message
http://www.gearslutz.com/board/low-end-theory/667529-new-roland-ua55-quad-capture-vs-presonus-22vsl.html
16.4.2 » Smaart Analyzing Tool » Go to message
Videos are always fun. I would love to see some user generated ones

Attached is a screen shot from Smaart of a transfer function analyzing the Eq applied to an output. The teal trace is the parametric filter and the red trace the graphic. You can also see this by looking at the trace register on the left if you forget..

Anyways, I used two parametric filters to for my system Eq. (note eq traces are plotted inverted). I then saved that trace and tried to recreate it with the graphic Eq on the console. What took all of a few seconds with a parametric took about 15-20 mins of twiddling with the graphic Eq, and it will never be as smooth as the parametric. In practice, spending that much time on this task would be ridiculous - especially when the results aren't justifying the means.

FWIW, I don't use the graphic at all anymore, except mixing monitors. I don't like being told which eq band to use. Graphics are all fixed frequency, so your hands are already tied as soon as you reach for it. With a parametric, even a semi-parametric, you have considerably more flexibility at your disposal, and you don't need to combine multiple graphic eq bands to get a response you can achieve with one filter and minimal phase (read as time) variation (if you are into that sort of thing). This is a bit of a ramble subject for me, I could go on and on (just search for my posts) about why the Graphic eq is lame - but I digress - some folks just like to take the long way home.

Cheers - C

16.4.2 » Smaart Analyzing Tool » Go to message
I have a 16.4.2 with the semi para eq and am able to set my curve quite ok. Once you work out how the different bands interact with each other, you can pretty much manipulate it any way you want.


That's the gospel right there bdhender! There is no reason to use your GEq for something that you can better achieve with the parametric - even with it being semi.

It's a common misconception that the GEq is the right, or even a good tool, for system Eq. Even the semi-parametric Eq will always give you positive results, and this way you still have your GEq to adjust while you are mixing - and you can return it to flat and your system is still tuned!

Live Sound » UC 1.7 Smaart Update » Go to message
Some have asked how the UC Smaart program compares to the Original Smaart program....... Meaning - if you measure with each software program - how well does it compare?

My Answer is: VERY well. The exact same room anomalies I found with UC - I found with Smaart v7. Feel free to measure with confidence....


Being that Smaart v.7 was coded using object-oriented programming architecture, we are able to port out the necessary libraries for Smaart 'modules' - or spectrum and real-time modes.

What this means for PreSonus is that you are using the exact same computational algorithms found in Smaart v.7. The data generated by Smaart v.7 and the SRA wizards will be identical provided that you use the same settings in Smaart as are set to SRA (1/3rd octave smoothing, 3 sec average, 50% coherence blanking).

Cheers - C
Live Sound » UC 1.7 Smaart Update » Go to message
Firstly, this thread rules. Huge thanks to Jerryd for getting this ball rolling.

I did indeed work directly with PreSonus to implement the Smaart functionality, including the screen shots and information for the manual, Wesley (PreSonus) and I worked very closely to bring all of this together.

anyways...

I would like to place the mic in front of each side and run the analyzer to EQ each side separately - without adjusting settings for the other side. Then I could make adjustments based on my ears to both sides. How do you use the analyzer to do left and right independently? Do I have to use different outputs on the board (other than main left and right)?


Yes, the main L/R bus are linked internally and are not able to be separated. For this situation it would be advantageous to use two sub group outputs for L/R. This is also something you would want to do to make two different systems have a similar sonic aesthetic, if you have unmatched boxes.

To add to the "where do you place the mic?" question - The simplest answer is - put the mic where you are putting the people! In other words, tune the speakers in the general area that the audience will be. When I'm outdoors (on the grass) I usually put the mic around head height, however indoors, I always put the mic on the floor and use a boom stand like a traffic cone so that it doesn't get stepped on

Also, as Jerryd mentioned in the OP, using the advanced analysis to generate an average trace of the systems response is in fact a much more powerful way to go - as you are making an eq decision based on a larger area, rather then optimizing for one location.

Cheers!

- C
16.4.2 » Smaart EQ saving options » Go to message
Max, to add to Steve's rocking reply, digital clipping (like an M7) is not the same sort of clipping that you would experience from an analog board (like a heritage 3000) - and is not a musically desirable artifact.

Dave Rat has a bunch of very awesome informational videos and papers floating around the interwebs; here is a link to one he made about gain structure. Really great stuff!!!

http://www.youtube.com/watch?v=1hwT15SSwgU
16.4.2 » Smaart EQ saving options » Go to message
Yes Steve! It's amazing how we can never stop learning when it comes to this stuff. I agree with you 110% - when I started taking advantage of and learning the technology we have available to use now, my gigs just got better and better every time out.


StudioLive General Discussion » Protools in/out settings » Go to message
I can't see your pictures, and when I downloaded them the resolution was too low to be able to make out any of the wording. :/

idk what interface you are using, because you didn't specify.

However, try deleting all i/o paths in your PT setup and then load the PreSonus template. I've done this with my 16.4 and 24.4 desks and they both work with PT flawlessly.
16.4.2 » Smaart EQ saving options » Go to message
Hello Steve - great post!

To answer your question about tuning vs ringing out - they are both fairly interchangeable terms for the same thing. Alignment also falls into this category, although there are subtle differences in them, they are all in effect to reach the same goal - a pleasant sounding PA system.

Tuning = Equalization
Ringing out = more equalization based on amplitude.
Aligning = adding delay to put individual speaker elements in time with each other, then use eq to smooth out the FR between elements.

With your main system - typically (read hopefully) you have your speakers in front of your vocal mic line on the stage - so the first offenders, as far as feedback frequencies from the mains, are going to be low frequency; as those are the frequencies that lose directionality and wrap around the speakers back to the mics. In my experience, the most aggressive main system tweaks are going to be in that frequency range, until you've got a sub bump below 100Hz, basically flat to 2k, and then a gradual drop off.

I would definitely run through the wizard and try to get a fairly tame trace before reaching for more Eq - as I mentioned above - flat isn't necessarily what you want to achieve in live sound. In fact, if you tune flat the system will sound quite bright, and you will not have the sub energy that you desire (this is also why tuning a system to be flat with an RTA is not at all ideal). While transparency is desirable for a recording studio or for music playback - with a live band flat can be quite awful.

After tuning, I can't recall any gigs where I've had to ring out my main systems - if I'm having feedback problems after I tune a PA, it is invariably because a performer decided to go into the crowd and got in front of a main speaker or I didn't bring enough dynamite and am pushing the head-amps too far - the system just sort of falls apart in these situations. It's my fault for not paying attention and turning his mic down, or my fault for not bringing a big enough sound system. Of course with monitors it is a whole other story because the speakers are actually pointed right at the mics. This is why HF feedback is more of a concern with monitors, and why the GEq can be such a great tool with them.

As a cautionary tale - have you had the experience where you ring out a mic, turn it up, then another frequency feeds back, then you turn it up and another frequency feedback, then you turn it up again and two frequencies are feeding back etc...? This is the biggest pitfall of aggressively ringing out a PA system (also why I strongly dislike 'feedback suppressors'). The more filters you slap on the system, the more 'holes' in the system, and the more it starts to misbehave - this is especially problematic of a system being pushed to it's limit, or in other words, a system too small for the job it is doing - OR - one whose horns need to get out of the way of the front vocal line - OR - one where you are pushing too much gain to the mic pre, and not enough from the main out, or amplifiers - OR - a system tuned too bright. Obviously there are many factors here - we call these things 'systems' for a reason!

I won't live with feedback just because my system is now set flat (after the wizard).


Remember, the SRA wizard doesn't set anything for you. It is you who places the eq filters based on visual and aural verification - the wizard shows you a general (general in comparison to full Smaartv.7 which is much higher resolution) idea of what the system is doing to the electronic signal you put into it as it comes out acoustically.

Cheers Steve!

- C

16.4.2 » Smaart EQ saving options » Go to message


I only really touch a GEQ for monitors



I agree with you, as I mentioned in my post above. Monitors love Geq.


16.4.2 » Smaart EQ saving options » Go to message
Right On! Yes, we designed the SRA to utilize the Eq already in the Fat Channel - the UI in the analysis adjusts the eq on the fat channel of the output you are testing.

I never have any issues getting the fixed parametric to work for my traces [with the SRA wizard]. Usually it takes no more then 2 filters, and I'm not cutting a whole heck of a lot, just making it so nothing is totally weird. What you may not realize is that the resolution of the analysis is actually the most smoothed value offered in full Smaart software, so I don't spend too much time tweaking on it.

As Gadget and I said, you can use the GEq if you'd like. FWIW I haven't used a GEQ for system tuning in many many years - once I learned that top level touring professionals and system tweaks haven't been using Geq's for system tuning for 20+ years, I decided to drink the special water, I only really touch a GEQ for monitors and live mixes. With the shows I work, I'm generally not mixing one band for the whole night, nor am I usually the only mix operator. I think of the GEq as a mix tool just like a compressor or gate - that it gets set for an act, but returns to zero for the next act because they require different settings. I (and the touring engineers that I system tech for) want to be able to put the system back to where it was configured during alignment - with the GEq off - after every act.

Have fun with it! Cheers -C



16.4.2 » Smaart EQ saving options » Go to message
Q1 - you've got both a 31 band graphic and a parametric eq on every output of the console, AFAIK, the dbx unit is redundant.

People can of course choose whichever Eq they wish to use. The reason why the analysis is populated in the Parametric is because that is the better tool for the job. There have been other posts on this topic. Basically the Eq's are for two different purposes. Parametric's are the industry standard for system tuning, or setting the table, for the live mix. Geq's are better suited as a mix tool.

I save my fat channel settings as a new preset in VSL, I'm not sure if this is the best way but it works and is repeatable, and any preset can be brought into any scene. However, I am of the school that you measure the system each time it is reconfigured. So as long as nothing changes, it is perfectly fine to use a 'room preset' for your rehearsal space - etc.

Q2 No - "you don't really got to smaart the kit for every scene you have on the console". see above. Tune the room, save the fat channel preset - use it on the main out for each scene.

Yes, you are thinking correctly. The headphone bus and the main L/R out are linked. Anything you do to its fat channel will apply to the headphones. A workaround would be to use 2 subgroups for main L/R and reserve the main out for headphone monitoring. Obviously this is a caveat - but the console has been formatted as such since it was initially released.

Q3 - Exactly. Now that you are aware of this functionality you can make the appropriate work around.

As a final comment of PEq vs GEq - there is no situation where making several notches on a Geq is a better idea then dropping one or two well placed parametric filters. Especially if you want to have an eq you can adjust during the show that doesn't effect the system tuning for the next act, etc.

You're VERY welcome, Max. I'm always glad to smooth out the wrinkles. Feel free to PM me orsskype if you'd like to have a good conversation! my skype handle is chris.tsanjoures

Cheers! - C
 
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