Using dual 31band EQ's for LCR to Give Audyssey a Head Start?

What are you trying to accomplish? Is it upper octaves or the bass EQ that you don't like with Audyssey?

What measuring gear are you using?

Audyssey can do some not so good things with some systems, that's for sure. I'm curious though what your issue is?

Audyssey doesn't need a head start!! There's no benefit of doing something like that!

Better to discuss:

1. What AVR/AVP do you have?
2. What are you unhappy with that Audyssey "does" to your system?

Maybe moving your query to the "Official Audyssey Thread" would yield more attention and help from all the knowledgable guys over there.

What sense does it make to screw up the signal quality by a parametric EQ and then have Audyssey trying restore some of the lost signal and then some ?

Well,...all I can wish you is: have fun getting your setup tighter,...whatever that means!! See Ya!

Keep in mind..
The most significant requirement is to balance the frequencies <300Hz...
If one doesn't control the LF room resonances, peaks and nulls, the rest of the audio spectrum will be muddied up..

Just my $0.02...

I would be prone to reverse the process and let Audyssey do its thing, and then use the parametric eq to overlay my own preferences on the system's sound.

And then you would get to the same result as gurkey described above: screw up the signal quality by a parametric EQ!

REW, OM, Audyssey. The bass EQ I use my DCX in concert with the SubEQ system, and Aud. does ok with the surrounds, at least enough for me, the EQ's would basically be more for the LS6's on the sides and that is it...I can't really describe what Aud. is doing to the system other than it doesn't really get my response all the way there. I wont require any ridiculous boosts, but I could, with some more tweaking, get my setup a lot tighter IMO.[/quote]

If you already own the parametric EQ, then throw it in and see what happens. Nothing to lose there. My only comment would be that the parametric EQ should be used only below the Schroeder frequency since it will likely do worse than Audyssey in every instance above Schroeder.

But if you're buying the EQ for this issue, I think it's a poor use of funds. Every additional EQ in the chain is going to eat up more and more headroom. The far superior approach would be to invest in more subs to correct the issues and focus on sub optimization with your measuring gear. Unless you have extreme amounts of headroom to start with, the brute force EQ is a very distant third choice compared to modal sub optimization and room treatments. Get that right and then either use Audyssey or the parametric EQ to fix what's left, but not both. Audyssey (and really all EQ) really works best as a fine tune, not to fix big problems.

Why would a parametric eq necessarily screw up the signal?

OK. I'd go for it. The fact is that Audyssey may not be the best solution in your situation. When it works, its fantastic. But I have first hand experience with poor Audyssey calibrations.

If you're not happy with what its doing I would eliminate it altogether and see how results are with the parametric EQ. It wouldn't surprise me at all if you preferred it over Audyssey.

Always think of a parametric EQ as a frequency dependent volume control (invented in the 20th century, BTW), in this case 31 volume controls (not much). How do you know which one to adjust and to what extent? Without taking frequency response measurements in the room to see what need to be corrected it is nothing but guess work, not anything we could call scientific.

The final result will be a room set to preference. As an example the parametric EQ setting will most like result in a frequency response anything but flat. Now you play an instrument that has a base frequency and lot of fundamentals (harmonics, 1st, 2nd, 3rd, etc.). With an uneven frequency resposne there is the likeliness that the ratio among the base frequency and all the harmonics will be changed, thus resulting in loss of fidelity, i.e. the instrument will sound differently than recorded in the studio.

The aim of Audyssey is to EQ each speaker channel (and it's interaction with room acoustics) to a flat frequency response.

Now if you use a parametric EQ in conjunction with Audyssey after running auto setup the para curve will prevail, i.e. you are going to have an uneven frequency response curve in your room set by the para, while Audyssey will be out of the equation since it has a flat response. But if you tweak the para and then run Audyssey, most likely Audyssey is going to flatten out your para settings as well.

Do it at your will, experimenting is free.
Edited by mogorf - 12/4/12 at 11:14am

You appear to be confused. An Eq with 31 volume controls would be a 1/3 graphic eq., not a parametric eq. The number of sections in a parametric eq is usually far smaller than 31, often only 3 to 6. Each section of a parametric eq has a frequency control, a bandwidth or Q control, and a depth/peaking or volume control.

God gave me ears, fingers and a brain and the time to learn. ;-)

So what? Having the resources to do frequency response measurements is not rocket science in this day and age. I have all that at my disposal as well. So do a goodly number of the people posting to this thread, it seems.

Which is far from a bad thing.

Since you are obviously very confused about simple things like the difference between a graphic eq and a parametric eq, why should I believe such a excessively global statement?

Reality is that the problem of non-flat response is not a failing of either graphic or parametric equalizers as classes of devices, but rather a problem relating to the people making the adjustments. If the people making the adjustments have the right training and resources, they will be able to get reasonably flat response no matter which kind of equalizer they have.

Heck, you don't even know which base is the right bass to use. You're going to lecture me about how to equalize an audio system?

That would hardly be a news flash. even if you weren't mangling the English spelling and syntax.

Of course. That's hardly a news flash.

Whether you know it or not, it is not written on stone tablets that everybody wants their audio system to have perfectly flat frequency response. My thinking was that if you had an equalizer and wanted to use it with Audyssey, one approach would be to let Audyssey do its thing unmolested, and then touch up system response with an independent eq to allow the listener to imprint his personal tastes on the system.

Thanks for trying to play, but...

When you will look into Audyssey technology (recommended) like MultEQ XT 32 you will see that it has more than 10,000 control points from 10 Hz to 24 kHz and in this regard 31 volume controls is practically nil. Don't you think so?

Our God given ears (+brain) are pretty good when it comes to listening to music and enjoying it but can easily fail when it comes to detailed measurements. Man invented instruments for that kinda job.

I thought you said you have good ears!

Preference can be good when it starts from reference.


Show me your flat measurement graphs, please.

See above.

I'm not talking about bass but base frequency.

Very strange approach for independently eq'ing on top of Audyssey with a third party device. Thanks for trying but not an advice worth to follow...(reasons I already described in my previous post.)

Take care.
Edited by mogorf - 12/4/12 at 12:53pm

As I said before, experimenting is free and there is absolutely nothing wrong with it, please do not misundestand me. What may be problematic is drawing the wrong conclusions!

Tell a bit more about your measurement technique, please. REW? Omnimic? How many measurements to you take? Same 8 as Audyssey or just one? Do you take utmost care to place the test mic to the exact same place as the Audyssey mic was placed? If you take 8 test measurements do you do an RMS averaging in REW or look at just one graph? Etc...

 

 

 

Unfair. Feri is Hungarian and his command of English is better than many of the native-English speakers who frequent these forums.

 

 

Yes, I agree. In fact I have been contemplating adding some form of external EQ into my own system (treated room, Audyssey Pro, Omnimic-tweaked) to try to deal with a pesky dip I have between about 400Hz and 1kHz. It's only about 5dB at its max, and I doubt if it causing any real audible harm, but it just irks me as my response from 10Hz to 20kHz is fairly flat after much tweaking and so on. I can't eliminate this dip any further using the Target Curve editor in Pro as the max it will boost is 3dB. I was thinking that external parametric EQ might let me flatten it a bit more - do you think it would be worthwhile, or even possible?

 

I'm not so sure, Feri. I have managed a very respectable FR using Audyssey Pro and then making manual adjustments based on my OmniMic measurements, such as using the Target Curve editor in Pro, and varying the sub delays in the AVP in order to improve the flatness around the XO frequency, but I am thinking that the ability to make small further adjustments, after running Audyssey, eg by using parametric external EQ, could be a good thing. I can't see how it can harm the Audyssey calibration to boost some frequencies a little in order to get a flatter, or preferable, curve.

 

In fact, I am already doing this to some extent. The amplifier in the Submersive subs has two different DSP modes - one of them (Pgm2) introduces a 3-4dB~ lift starting at around 40Hz. By running Audyssey with the subs in Pgm1 and then, after running Audyssey, changing to Pgm2, there is a subtle but important flattening of the curve at the bottom end. Audibly it is significantly better.

 

This graph shows the effect of using Pgm2 in this way:

 

 

 

 

 

 

 

 

I am a huge Audyssey fan too (and my sig is even more revealing than Feri's :) ) but I agree with you. Audyssey is just a tool and like any tool, in the right hands it can be made to perform better. Audyssey is great for the average guy who just wants to run a few chirps and let the software get him a reasonably good result, right out of the box. In its XT32 form, it is very, very good. But not perfect.

 

 

Yes, this is exactly what I am thinking too. A couple of additional filters and I'd be flatter as well. Got to be a worthwhile objective surely?

 

I/m not sure it matters if the subsequent OmniMic tets use the exact same mic positions, Feri. The idea is not to try to verify what Audyssey has done, but to improve on it. Once Audyssey has done its thing, the result at the MLP will be pretty good. Measuring at the MLP and seeing the actual in-room response (as opposed to Audyssey predicted responses - the famous 'after' graphs) then enables you to make adjustments that will improve the sound even more at the MLP. I have done this on many occasions and improved Audyssey's calibration every time - the most quoted example in the Audyssey Pro thread is the 'sub distance tweak' where measuring and then manually changing the Audyssey-set sub distances can give a huge improvement in the FR around the XO region. Almost everyone who has done this has found similar improvements. Audyssey often seems to struggle to optimise the FR around the XO region and benefits from post-cal tweaking.

 

EDIT: Audyssey often seems to struggle to optimise the FR around the XO region and benefits from post-cal tweaking. Not surprising really since Audyssey doesn’t do any further measuring or calibration of the combined response of the LCR channels and the subs. They are measured separately and filters are created accordingly, but they are never measured together (which is an Audyssey failing IMO).

Edited by kbarnes701 - 12/4/12 at 2:09pm

I'm being flattered here Keith, ain't I?

Keith, you also know the general advice of taking out every possible filter (and any additional circuitry) out of the way of Audyssey prior to eq'ing a subwoofer. Crossover set to max., phase knob set to 0, best if sub amp has an LFE input bypassing this kinda stuff, and all that jazz. Now you want to introduce another set of filters into the chain in form of a PEQ. Care to reconsider?

That's advice for folks without measuring gear and it doesn't apply to more complex systems.

Audyssey is not the only tool in the shed for those with the knowledge and measuring gear.

IMHO, it's not a question of having measuring gear or not, but a question of adding additional circuity into the chain or not. My position is that it is not advisable to clutter the system with circuitry that may add unpredictable results like phase distortion that may result in unwanted lessening of audio-fidelity at frequencies affected when it comes to odds adding up. On the contrary, feel free to use a PEQ, but make sure to turn Audyssey off. Dual systems are always harder to handle (and troubleshoot) than single systems. Agree?