[Russell.Williams]

So, I've been lucky (sad?) enough to have had all of the common dedicated subwoofer EQ devices through my room. Far from deciding that there is a definitive pecking order, it seems to me that each has it's own strengths, be it price, automation, manual tweakability, etc.

Never-the-less, we all like a good EQ discussion, so as the success of an EQ is it's ability to provide a smooth/flat and indeed short response. There is a general forum 'opinion' as to which is best, I thought I'd invite the brave to pick which was which from their respective waterfalls produced using REW which doesn't care which device it was measuring. All are produced using the humble Monolith and I apologize in advance for the slightly differing perspectives and frequency ranges used, but I think the effectiveness of each device used can still be seen.

So, with the exception of 'No EQ', I've blanked the names of (in no particular order) the SMS-1, AS-EQ1, 8033 Anti-mode and A N Other budget device I have been playing with and invite you to say which is best and why:

<EDIT>Somehow I deleted the original image from Imageshack () so I've reposted the reveal in order to make some sort of sense of what's going on. Repeat 100 times, I am an idiot, I am an idiot......

[eviljohn2]

On graphics alone, I'd take the bottom one. A reasonably flat start and certainly the friendliest in the time domain.

[Moonfly]

Well it seems a bit of a toss up between the first and third or fourth for me. The first one is the flattest looking while the 3rd/4th seems to solve ringing best. Personally I always go for flattest but then I do EQ'ing manually.

Not sure which I'd pick as best yet just thinking through, but what are you after, a 1-4 order, or do we guess which is which, or do both? Going first is going to be sticking ones neck out on the line

[AngelEyes]

The one that sounds the best is.

Adam

[IRobot]

Yeh, bottom one looks best so is probably AS-EQ1. Purple one looks good in time domain but hasn't sorted out the trough so maybe it's the Anti-Mode. The light green looks flat but hasn't done anything for the ringing, BFD ? That just leaves the blue one, SMS-1 ?

[AngelEyes]

Ok, I'll bite

Logic (mine at least ) dictates the best result is most likely to come from the device that uses REW to choose its filters and as its visual guide. If you are using REW as your guide then you should achieve the best results via REW as well.

On the backhand of that logic, the worst results will most probably be those 'automated' products that use their own algorithms to decide what is optimal, and the EQ1 in particular I would expect to produce among the 'worst' results when displayed in REW as it is optimising over an area, rather than a point source.

I am assuming the Anti-Mode is optimised for a single position? This is the trickiest for me as I don't have any experience with it.

The SMS-1, assuming REW was not used to choose the filters, is easy enough to make flat but without precision in the filters it is likely to ring quite a bit.

So I have a few caveats but as I slowly ease my head into the noose my guess is:

Bright Green: AS-EQ1
The guess being it likes to boost the signal level and then chop things down.

Purple: AntiMode

Blue: SMS-1

Dark Green: A N Other

The more I think on this the harder it gets

Adam

[pws]

Head on block time

SMS-1 is the first graph....does not resolive rigning

Anti mode is 3rd graph...less ringing especially lower down and does not touch the dip but quite flat overall


The resi I have no clue


What the prize Russ?

[AngelEyes]

Originally Posted by pws

What the prize Russ?

Public humiliation for those that get it wrong

This thread made me think of the post Pepar pointed out on the AS-EQ1 thread, which questions the usefullness of exercises such as these.

This and some recent posts got me thinking that we have a paradox here akin to Gödel's Incompleteness Theorem. Here is my version of that as it applies here: "An audio system measured with any tool whatsoever can be made to look perfect when measured with that same tool afterwards". This is a universal theorem and applies to all measurement systems I know of, including MultEQ.

When I hear about how smooth the graphs look with one method or another I can't help but smile. The person writing that is making an inherent assumption that the method has some correspondence to what we hear. "I know flat is good and I get flat on my beautiful graphs so my method is great".

Many years ago the Audio Engineering Society conducted a bake-off among the leading (at the time) speaker measurement systems. The creators of the software were invited to measure a speaker in the the exact same position in the same room. The results were disheartening: every method produced a completely different result! The theories behind each method appeared correct and speaker manufacturers still use one or another of those tools today and produce beautifully flat measurements. But, when measured with a different tool they look different.

I don't want to turn this into a marketing op-ed for MultEQ. But, I do want people to know that before Audyssey was even a glint in our eye we were performing research at the university to understand why these things happen and how to get around them using an intersection of knowledge from acoustics, adaptive audio signal processing, and psychoacoustics.

--- Chris Founder / CTO Audyssey

This really rings true in my experience as my graphs for the AS-EQ1 didn't look flat at all but sounded fantastic, much better than flatter looking graphs created with the SMS-1 for instance.

Adam

[ben.bayliss]

I won't enter the 'which is which' debate, but my preference would be for the purple one, although it still needs that 58Hz looking at, which is probably a room node and there's nothing you can do about that.

That said, I'd be more interested in looking at overlaid curves from many locations within the room. It's easy to flatten a system in one spot, but it'll probably sound dreadful elsewhere.

[Moonfly]

Interesting quote Angel, and I can see the point clearly. FYI, I use REW to try double check Audyssey etc and have found some comfort in that I'm using 2 methods of measurement so each checks and hopefully confirms what the other does.

For the most part they pretty much do and are consistent so I think that gives the 'flat response' target some weight in my mind.

Thing is this is purely from a technical point, and just to make sure i miss non of the source material or get audible booms etc, which actually acts as another back up I suppose thinking about it now. Over time though I started messing with different curves and started to notice I liked a less than flat curve better for certain things. Then over time I started to realise different curves were better for different source and materials. I came to the conclusion the flat response is something to aim for as your starting point, really just setting up a Datum from which to work through.

Ive got an EQ-1 on its way for trial and I'm hoping to see it produce a less than flat curve to confirm what my ears tell me, if they should even be questioned really.

IMO, as long as you response has no dips, and no massive singular peaks the only thing that matters is how it actually sounds. I think I saw Russell comment that he ended up ignoring the actual response, instead eventually opting to look at the overall curve and ensure no bad singular anomalies. I have to say, I tend to agree with that analysis.

[al_bert]

Originally Posted by IRobot

hasn't sorted out the trough

None of them has, as it is impossible. The nulls vary in frequencies, but they are there.

(I expected a little better out of AS-EQ1 though, as it has been advertised to improve the time domain.)

[paulst10]

Originally Posted by al_bert

(I expected a little better out of AS-EQ1 though, as it has been advertised to improve the time domain.)

They have all made time domain corrections

[Moonfly]

Originally Posted by paulst10

They have all made time domain corrections

You know, its possible standard eq'ing will effect the time domain a little anyway, so this could change without the device doing anything to it.

Just to make it more difficult

[paulst10]

Originally Posted by Moonfly

You know, its possible standard eq'ing will effect the time domain a little anyway, so this could change without the device doing anything to it.

Just to make it more difficult

Yes, I know, I was just pointing out that they all have had a time domain correction of one form or another

Sticking my neck out here You can clearly see the SMS-1 (light green) as Russell has cut below 50hz then upped the SMS-1 internal volume resulting in an opposite shift of ringing above 50hz ish

The light blue is the AS-EQ1 edit: 100% confident on this.

And while I'm here, the purple is the Anti-mode ?

(I think)

[AngelEyes]

Originally Posted by paulst10

Sticking my neck out here You can clearly see the SMS-1 (light green) as Russell has cut below 50hz then upped the SMS-1 internal volume resulting in an opposite shift of ringing above 50hz ish

That makes sense, I just wouldn't expext Russell to use that technique so I assumed the AS-EQ1 would be the only device to do that automatically, however the ringing and the top end isn't in keeping with the AS-EQ1 really.

When you factor in the possibility of Russ using different methods on the two manual devices it becomes a lot harder to pick them out.

Adam

[Moonfly]

Originally Posted by AngelEyes

When you factor in the possibility of Russ using different methods on the two manual devices it becomes a lot harder to pick them out.

Adam

And possibly shows just what you can achieve with manual eq and a bit of enthusiasm to gain the required know how, maybe.

[mojogoes]

I'm thinking No1 = lite green is good/best and the last one is the one that Russ has been tweeking about with = cheapest unit.

[AngelEyes]

Originally Posted by Moonfly

And possibly shows just what you can achieve with manual eq and a bit of enthusiasm to gain the required know how, maybe.

Sorry I don't quite understand what you mean?

Adam

[namuk]

3rd image i.e blue , more sustained and solid and good the the Ears . not all over the place like rest ..

[Zorba_8]

Will Russ be revealing his answers soon?

Or "answers on a postcard?"

[paulst10]

Originally Posted by Zorba_8

Will Russ be revealing his answers soon?

Or "answers on a postcard?"

It's just a toss up between the light & dark green really as one of them is the SMS-1

The light green has the opposite shift in ringing above 50hz which could be caused by reasons mentioned earlier, but the dark green is too flat to be an auto EQ IMO

The purple is Anti-mode & blue is EQ1

[AngelEyes]

If you are right about the SMS-1 (I think you probably are), it is the perfect demonstration of how 'flat' will not always equal 'good'. Only having the 2 dimensions to work with means you can't see the ringing generated around the crossover area that wasn't even there before.

I would love to know how much of that is caused by phase adjustments in order to produce a 'flat' crossover area?

Adam

[cribeiro]

In this graphs you can "only" read the frequency response and the decay times. This says nothing about timing (phase), AFAIK. And as we have learnt, one big advantage of the AS-EQ1 (and also antimode?) is that it corrects the phases, which plays an essential role.

[j0hn]

you guys should get a real system and forget all this faffing around

[paulst10]

Originally Posted by j0hn

you guys should get a real system and forget all this faffing around

Where's the screen go ?

[j0hn]

Its just bellow the electronics on the pillar... it expands outwards at the touch of a button and thus destroys all EQ. Thats why its retracted, this is a music only system, images are better created without a screen, screens are so yesterday....

....but they include one for the old timers

[gperkins1973]

Just out of interest how do the Behringer Feedback Destroyer EQ's compare to the others on the market like the Anti Mode and the SVS EQ1.

There are a few BFD models but didn't know which one is the best one to use. Price wise they seem very cheap. Are they automated like the others or is a case of manually EQ'ing the BFD's.

Do you need REW to get the full benefits of the BFD's or can you use them without REW.

Also how do you connect them up.

cheers

Graham

[cribeiro]

Originally Posted by gperkins1973

Just out of interest how do the Behringer Feedback Destroyer EQ's compare to the others on the market like the Anti Mode and the SVS EQ1.There are a few BFD models but didn't know which one is the best one to use. Price wise they seem very cheap. Are they automated like the others or is a case of manually EQ'ing the BFD's.
Do you need REW to get the full benefits of the BFD's or can you use them without REW.

Also how do you connect them up.

cheers

Graham

BFD is not automatic, and very difficult to use without REW (I'd say impossible unless you are an expert in the field). AFAIK, BDF does not correct the phases, which plays an essential role for bass timing.

[AngelEyes]

Originally Posted by gperkins1973

Just out of interest how do the Behringer Feedback Destroyer EQ's compare to the others on the market like the Anti Mode and the SVS EQ1.There are a few BFD models but didn't know which one is the best one to use. Price wise they seem very cheap. Are they automated like the others or is a case of manually EQ'ing the BFD's.
Do you need REW to get the full benefits of the BFD's or can you use them without REW.

Also how do you connect them up.

cheers

Graham

Lots of questions, all discussed before at some time or another. Check the stickies and use the serach, and Google because some info can't be linked to from these forums. BFD Guide would be a good search term to use.

[gperkins1973]

Hi chaps

I am going to have a read up later today.

This seems to be a new 2009 BFD out. Has anyone had any experience with one of these or know of them if they are any good. And how this would compare with Anti Mode.

Behringer DEQ2496 Mastering Processor | DV247

cheers

Graham