# My initial readings



## Dimitri_ISF (Jun 19, 2010)

Hi,

I've been using the BFD and REW for some years now with good results.

But with my latest setup I've been having difficulty equalizing my subwoofer(BK monolith) with the BFD 1124. 

My speaker setup is: 2 KEF Q11 towers.
3 Kef eggs.

Crossover for all the speakers is 80 Hz. on my Onkyo tx-sr607.

I've posted some photo's of my setup and my first readings without EQ.

Main problem is boomyness and a sub which can be localized on many occasions. 

My usual method for applying filters is to make a measurement, pull up the filter adjust tab on REW and just create manual filters to get a somewhat flat response, and this is usually enough. But I feel this situation calls for something more. 

Can you guys help me to use the more advanced featured of REW like the spectral decay plot. I can recall JohnM talking about using this, but I wouldn't really know what to look for in this graph. I've posted 2 graphs to illustrate my situation.

If I left anything out please tell me.

Any help would be appriciated.

Dimitri.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Is this a full range, or sub-only graph?










Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Hi wayne,

This is the monolith and the Q11's in stereo.

Dimitri.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Thanks. Do you have a graph with the sub equalized, without the main speakers?

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Here they are.

Just the sub with EQ and one without EQ.

Dimitri.


----------



## Dimitri_ISF (Jun 19, 2010)

...


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Okay, I see the problem. Notice the upper end of your unequalized graph, how response roughly traces the Target curve. On the equalized graph, everything above 80 Hz is elevated. 

It looks like you applied filters that affected response all the way up to 150 Hz, or even higher. That’s why you’re having localization issues. There’s usually no reason to apply filters above the crossover frequency designated by the receiver, or even close to the crossover point.

I suggest eliminating any filters you have above about 80 Hz. If that doesn’t take care of the localization problem, try using a house curve. That would pull down the sub’s upper frequencies further.

Keep in mind that it might be impossible to achieve 100% non-localization. A program that has severe bass levels in the 90-100 Hz range could functionally “blow out” the crossover, much as your equalization has. There’s not much you can do about stuff like that, you’re at the mercy of the program’s sound mixers. Nevertheless, eliminating EQ filters above 80 Hz is the way to go.

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Thanks wayne,

I never appllied filters above 85 Hz. orso. I was surprised to see the subs response at the higher frequencies though. I believe this is caused by the method I used to get the lowest points of my sub response at the 75 Db. level. I just raised the sub volume a few times to get the lowest points where I wanted them, and apply extra filtering to the peaks that have also been lifted. That's the way I use to get an even response along the whole range, And with the mains active in my measurements I didn't identify the peaks that were created as being the sub. I just figured it were the main speakers.

Is this a good method to get an even response?. Or should I just leave the dips where they are and just focus on the wild peaks?.

Another point is that I find the new KEF's to be a little too aggressive. To the point where the sound can become a bit annoying at times. The peak I have at 80 Hz. also affects my mains response I believe. I've added a graph of the response from the Q11.

Dimitri.


----------



## Dimitri_ISF (Jun 19, 2010)

Here it is.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

> I just raised the sub volume a few times to get the lowest points where I wanted them, and apply extra filtering to the peaks that have also been lifted. That's the way I use to get an even response along the whole range, And with the mains active in my measurements I didn't identify the peaks that were created as being the sub. I just figured it were the main speakers.


Yeah, I’d say that’s a problematic approach. If you were cutting everything down to where the 78 Hz null is, and nothing above 85 Hz, that would result in the response you ended up with. 

Cutting everything down to the lowest depression, or boosting everything up to the highest peak means you’re essentially using the EQ as a gain control. This is poor use of an equalizer. You might want to review my Minimal EQ article – there’s a link to it in my signature.

Also, leaving the mains running when equalizing is another no-no, because as you noted, you can’t readily tell what’s coming from the mains from what’s coming from the sub.

Take another look at your sub-only graph. Your best bet would be to raise the Target up to about 77-78 dB, and get response to track the Target, using both boosting and cutting filters.










Regards,
Wayne


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Dimitri_ISF said:


> Here it is.


Hmm, looks like the mains are running full range. There’s no evidence of the 80 Hz crossover reducing bass response even a little bit.

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Hi wayne,

I'm not sure what you mean by raise the target?.

Dimitri.


----------



## Dimitri_ISF (Jun 19, 2010)

Wayne A. Pflughaupt said:


> Hmm, looks like the mains are running full range. There’s no evidence of the 80 Hz crossover reducing bass response even a little bit.
> 
> Regards,
> Wayne


Wayne,

You're right. This measurement was taken with the mains at full range.

Dimitri.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Dimitri_ISF said:


> Hi wayne,
> 
> I'm not sure what you mean by raise the target?


The Target Curve is the blue-green line that traces the response of the subwoofer crossover. Typically it sits at 75 dB, but it can be adjusted up or down. Look for the “Target Settings” icon on the left side of the screen.












Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Ok, will do.

It's back to the drawingboard then. I was wondering though, when creating filters, do you guys let REW calculate the filters, or do you just create them manually?. Is there a smarter way to get the right filters?, like using the spectral decay plot?.

Dimitri.


----------



## glaufman (Nov 25, 2007)

You'll find that most people let REW create them, then tweak from there, sometimes eliminating a few entirely...


----------



## JohnM (Apr 11, 2006)

Dimitri_ISF said:


> Is there a smarter way to get the right filters?, like using the spectral decay plot?


REW V5 provides a predicted waterfall plot that updates live as you adjust filter settings, that can be useful if trying to target a specific resonance. The V5 filter assignment and optimisation algorithms are also more powerful than V4.


----------



## Dimitri_ISF (Jun 19, 2010)

Ok,

I'll install the latest version tonight.

One more question before I begin filtering: When I want to introduce a house curve, should I start differently?. Does it take another approach?.

Dimitri


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

All you need to do is load a house curve file. Look for the “House Curve” tab in the “Settings” window.

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Hi,

Do I need to create a house curve file myself?.

Dimitri.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Yes, the REW Help Files includes directions on how to create a house curve file.

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Hi,

I've loaded a house curve with a 6 Db. raise at 20 Hz. and 0 at 80 Hz.

I've made measurements without EQ and let REW assign filters.

It's telling me to use 2 12Db. boosts on the behringer... Isn't that a bit much?. I remember that in the past people said never to boost more than 5 Db. on the behringer...

Dimitri.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Can you post a screen shot of the EQ panel (or at least list the filters and parameters), and your response measurement?

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Hi wayne.

Here they are.

Dimitri.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Thanks. Looks like your fine. There are plenty of severe cuts to go along with the boosts. Actually, that can be just as bad a severe boosts, because severe cuts leave severe peaks between them. 

Re the boost at 77 Hz: If that filter did not eliminate the depression, then you should remove it. That one looks like it might be a null.

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Hi,

I've added a picture of the response that I now have.

Sounds a lot better this way with way more transparent sub sound. I could use a little bit more "slam" though. It sounds very balanced, but a bit more punch would be nice. Maybe boost the lower end a bit?...

I'm also thinking about a bigger center speaker to match the Q11's. Something like the KEF bIQ6 C. Would youi guys say that's a major upgrade from the Egg?...

Thanks,

Dimitri.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

> Maybe boost the lower end a bit?...


Maybe try a steeper house curve...




> I'm also thinking about a bigger center speaker to match the Q11's. Something like the KEF bIQ6 C. Would youi guys say that's a major upgrade from the Egg?...


Yes, I think the bigger speaker would sound much better.

Regards,
Wayne


----------



## Dimitri_ISF (Jun 19, 2010)

Wayne,

I'll trie a steeper curve.

And upgrade to the KEF IQ6C.

Dimitri.


----------

