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hue
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Maybe this is a naive point of view but to me all of this clinical stuff is secondary. Sure it's great to have tools. Knowing the room is a great place to start. In my head, it makes more sense to use your ears. Play a cd and see how that sounds. And hey, what's an opening act for anyway? Sure you don't want an opening act to sound bad. Sure you want to do the brunt of the work in sound check but tweak with the first couple of songs. Why not?

There was a time when all of this high tech gear was just a dream. There are still some vinyl recordings that I hold in high regard above many digital ones. From days when the highest tech they had was an oscilloscope and a voltmeter. Ok. I exaggerate a bit. Still. Do you think Allan Parsons pulled out a spectrum analyzer when he mixed Dark Side of the Moon? Probably not.

Bottom line being that tools are nice. Knowing your gear is good. In the end ears don't lie.....much. If it sounds good, it can't be bad.
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talmen
Presonoid
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Agreed. Your ears (combined with your brain, of course) are the single most important piece of gear that you have at your disposal.
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Jerryd
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Joined: 28/07/2010 16:01:24
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hue wrote:Maybe this is a naive point of view but to me all of this clinical stuff is secondary. Sure it's great to have tools. Knowing the room is a great place to start. In my head, it makes more sense to use your ears. Play a cd and see how that sounds. And hey, what's an opening act for anyway? Sure you don't want an opening act to sound bad. Sure you want to do the brunt of the work in sound check but tweak with the first couple of songs. Why not?

There was a time when all of this high tech gear was just a dream. There are still some vinyl recordings that I hold in high regard above many digital ones. From days when the highest tech they had was an oscilloscope and a voltmeter. Ok. I exaggerate a bit. Still. Do you think Allan Parsons pulled out a spectrum analyzer when he mixed Dark Side of the Moon? Probably not.

Bottom line being that tools are nice. Knowing your gear is good. In the end ears don't lie.....much. If it sounds good, it can't be bad.


Using a spectral analyzer in the studio to mix with -- probably not -- never heard such a thing. If it was a live show in the mid 80's -- you betcha there was a FFT analyzer around. If that band had any connections with some of the guys that invented this stuff -- then I guarantee you -- there was one around there somewhere.

I really don't get you guys. Why wouldn't you use all of the available tools that you could get your hands on?

Do you truly understand WHY guys bother to use one of those devices? Seriously, WHY do they use it?
Have you ever used one on your system?

I hate random blanket statements without foundation.

If your ears are really that "Golden" then congratulations BUT I really think you are missing out on the "WHY" part of it all. I will agree that the ears are the FINAL judge BUT you don't know what good is until you hear good first.

Let me ask you a very basic question: IF a graphic EQ is set FLAT -- does that mean your system is FLAT?
gadget69
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Joined: 21/09/2010 03:56:19
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There are a few things at play here...we all hear things or "perceive" them differently. We also do not hear all frequencies with equal efficiency...see "equal loudness curve" that shows clearly that our hearing is most efficient in the 600-4K region, and falls of dramatically after that.

But when it comes to loudspeakers, all that we are trying to do by "flattening the system response" is getting an equal energy output form all frequencies. That way your not having to use equalization to make up for some deficiency in the speakers, and believe me, most speakers have wild deviation from flat response.

That is not to say that a purely flat system will be everyone's cup of tea, (although once you start "mixing" on a flat system it becomes obvious it's much more responsive to sonic adjustments...) but it certainly allows for a much better canvas to paint your sonic masterpiece on. (I'm sure digin the Studiolive for helping paint that masterpiece...I find I have so many more tools to work with, and the adjustments I make are so much more audible than with even my $20K Soundcraft analog mixer)

As for using strictly pink noise and an RTA to tune a system indoors? Unless you have a common flat reference of the system to start with, you will have NO way of knowing what that room is doing to the sound. Further, the RTA based system takes into account typically only the ISO center frequencies (generally 28-31 reference points) that correspond to most graphic equalizers "sliders".

As Jerry pointed out, RTA based measurement systems take only the ISO specific energy available at the measurement mic into account. If said mic is on a stand in the middle of the space to be measured there are so many paths to the mic that cancellations are inevitable, and that renders the whole process mute...move the mic even a few inches, and a whole new set of arrival paths are generated.. and they skew the measurement process dramatically.

With FFT based systems what were trying to achieve is make sure what goes out of the mixer, is an accurate representation of what is coming out of the speakers...Things like time, phase, polarity, driver alignment, and impulse response are completely ignored by the RTA based system.

What we have done at the dbx forum, is take a tool provided (flawed as it is) and make it useful. The Auto Eq is certainly far from plug and play, but with years of experimentation and trial and error we have arrived at a fairly strait forward and simple process to make your system sound better, and get a good starting point without having to have a degree in sound physics...

But the one thing we always try and stress is what sounds best to you is whats important, and the ear is always the final say...but are you SURE you know what your hearing?

This message was edited 1 time. Last update was at 20/10/2010 13:06:51

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Jerryd
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Joined: 28/07/2010 16:01:24
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Gadget -- you always have a better way with words than I do. I will post some screen shots of my system and maybe I can demonstrate what we are talking about.

Here is a picture of my system (Top, Mid & Sub) just one stack. It has NO EQ on it at this point whatsoever. It only has the recommended crossover points in place and gain structure. Here it is: Pay attention to the "MAGNITUDE" window (bottom window)



At first glance -- this looks ugly! Look at the 3 - 3.5k region. It is sitting at -6dB down from the start. Now take a look at the 50Hz region. It is naturally sitting at plus 12dB right out of the gate. Well, the low end build-up here is intentional on my part because I like strong low end. This was controlled by LEVEL setting of the poweramp & crossover BEFORE any EQ applied.

What Gadget pointed out is that THIS response has UN-equal energy between frequencies. Just look at the picture....... there is nothing equal about it. So the goal here is to make them more even with each other because that gives you a very good starting foundation to work with.

No matter how good my ears are -- I could NOT hear these irregularities. All I can do is fiddle with a graphic EQ or the channel strip mixer and HOPE I can get it to sound OK. I don't want to do that because it wastes huge amounts of time and makes mixing a live band not very fun. When the show starts -- I don't want to be on the diagnostic side of the mixer. I want to be on the creative side of it and I will tell you -- it is way much more fun.

An FFT analyzer does much much more than tell you about the above flaws in the response. It allows you to "Time Align" the individual drivers at the EXACT acoustical crossover point. When you set your crossover to say 100Hz for the sub to the top -- that is in the electrical domain of that device. Since my low end build up is strong because I have my sub amp turned up -- my 100Hz electrical XO point just got shoved upwards into the 120Hz range. I think I aligned the top to the sub at 120Hz -125Hz range. But it is aligned in the acoustical domain and that is MOST important. You CAN'T do that by ear.

After I set the XO & levels between components -- I then aligned the boxes. The end result is the above.

Now after all of that was done -- I then moved onto the Equalization part. Looking at the trace above -- you can see where CUTS needed to be and BOOSTS to the respected frequencies to FLATTEN out OR SMOOTH out the HYPE or LACK in the system.

Here is my final product:



I now have a very smooth Phased Aligned system with the kind of low end build up I prefer. I do have to say this was all set playing pink noise thru the channel input on the mixer with NO EQ engaged, No compressors, limiter, gates, NO NOTHING engaged but pure clean pink noise.

I use pink noise because that is the industry standard and it is the only KNOWN you can count on. This was also done outside removing as many reflections as possible (Except the ground) BUT it was FREE and nobody I know has access to an anechoic chamber so it makes very good sense.

The EQing that was done was completely done using PARAMETRIC Filters because it is much more specific that a graphic. Wherever there was a boost or cut needed -- I can zero right in with the parametric and drop it into place and correct it without affecting other frequencies around it. With a FIXED graphic EQ -- it is impossible to do this. Your exact problem area has to fall (if you are lucky) right on the exact fixed filter. It rarely happens.

I have tuned a few systems with only a graphic and it is a PAIN & not recommended BUT if it is all I had -- that is what I would do.

I use NO graphic EQ's. The way graphics are oftened used is in GLOBAL position. Although great for damage control -- it is awful for clarity of the higher frequencies. The above trace (finished) is MY GLOBAL position and once completed -- doesn't get touched anymore. It gets LOCKED up & no one can change anything on it.

All other EQing is done on the channel strip of the SL (nice clean canvas) and is great for shaping and carving out pockets for all the instruments to sit in.

THAT part is done by EAR. You don't use an FFT analyzer to set instrument EQ's.

Gadget has an article on the DBX method over on the forum there & it doesn't require an FFT program. It is the method I used to use before I got into Smaart & it really does work. All you need is a measurement mic and a system controller.

So what is better.........an FFT analyzer or the EARS? I say BOTH. Also, if you have never used a Dual FFT program or have heard one -- Don't knock it til you try it. You won't go back.

Any day now -- Big Joe Daddy is going to use an FFT analyzer on his system. I will have him post his report. Mono -- has already done it & is very happy.

This message was edited 1 time. Last update was at 20/10/2010 17:21:22

kibo
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Joined: 28/07/2010 23:08:13
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hi jerry,

im so excited to learn from you guys... learned a lot... eversince you shared things about how to try to Flatten the system, i completely get what you mean... hopefuly soon i could complete my set up and try to play and learn. tnx... of course to mono too!

keep it up guys,

kibo
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Peary Forrest
Prenoob
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Joined: 28/07/2010 20:29:36
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Nice tutorials Gadget and Jerryd, So Jerry, how many filters did it take to level that out and did you use the ones in the driverack and another unit?
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kibo
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hi jerry and mono,

a second hand store near by is finally selling the line 6 UX1 for $65CAN. just want to make sure if this one will really work with dual FFT. please let me know. i will buy it tomorrow if you guys will give it a go. i just felt that maybe this UX1 is more appropraiate for guitarists... i may be wrong... anyway, hope to hear from you...

kibo
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Monolithent
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Hey Kibo,

It looks like a winner. Just to be safe, though. Hang on to the receipt in case it doesn't play nice.
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My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

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kibo
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hi mono,

ok tnx.... and you said behringer mics would be ok to go with it?

tnx,

kibo

This message was edited 1 time. Last update was at 22/10/2010 00:37:13

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Monolithent
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Yeah, they'll be fine for now. You don't really need Earthworks level of fidelity at this point. You can upgrade later if you feel the need but that's likely several years out.
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Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

StudioLive 16.4.2, AudioBox 1818VSL, AudioBox 44VSL, Faderport, Digimax FS,, M-Audio Firewire 410
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hue
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Jerryd wrote:Let me ask you a very basic question: IF a graphic EQ is set FLAT -- does that mean your system is FLAT?


Of course not but if you can't hear that there is something blatantly wrong, there is something wrong with your ears. I understand the use of tools but the bottom line is, the tool is only as good as the person using it. If you can't hear that a room is sucking mids there is something wrong with your ears. Sure you're going to compensate for it but how is an RTA going to change that? Yes, it may affect how much you compensate but you will still compensate.

After all some time we like the sound of imbalance. That's why people go gaga over vintage gear. Do people like the sound of saturated tape because it is harmonically flat? Hell no! Do people like Neumanns because they accurately represent what they "hear". Of course not.

Yes, it's great to know that your monitors are doing what they are supposed to do. That's great. If you have the tools to ensure that they are flat, that's awesome. I'm not saying tools are bad. I just think that good sounding gear has been around a lot longer than the tools to "perfect" their sound.

I imagine the only real way to calibrate your monitoring system would be to use an anechoic chamber, several measurement microphones and a stepped graphic equalizer which you would probably have to replace or recalibrate every year or every other year. What a joy that would be. Not all of us can afford that luxury.
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kibo
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hi jerry and mono,

installing the drivers for line 6 wouldnt create any problems with presonus drivers, right? i might be wrong but i think it has only one input... there is just an option on using XLR mic or 1/4 inch input. i think it wouldnt work for FFT. i might be wrong. sorry for the hassle....

thanks,

kibo

This message was edited 2 times. Last update was at 22/10/2010 07:25:40

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Monolithent
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Hey Kibo,

Sound on Sound reviews says its a two in two out configuration and a few other places. There isn't a lot of data available on the UX1. But just to be safe, hang on to the receipt and make boubly sure you can return it in case I'm wrong.
http://support.presonus.com

Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

StudioLive 16.4.2, AudioBox 1818VSL, AudioBox 44VSL, Faderport, Digimax FS,, M-Audio Firewire 410
--MultiBoot System--
Win Vista 64/XP Pro/7 x86/7 x64 - Mac OSX Snow Leopard/Lion
Gigabyte motherboard--SYBA TI Firewire XIO2200A--i7 2600k Quad Core--16 GB DDR III--Custom 2U Rackmount--4 TB Raid (all internal SATA II)--19" Samsung HDMI LCD on pivoting VESA 1U Mount
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jims
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kibo wrote:hi mono,

ok tnx.... and you said behringer mics would be ok to go with it?

tnx,

kibo


These are the mics I use on my reference system. They come with the calib file..

These guys also have the Behringer available if you want..

http://www.cross-spectrum.com/measurement/calibrated_dayton.html
 
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