Question about coaxial drivers, directivity vs equalization

[Honken]

A single high shelf filter would probably be a better option to lower the treble, than letting DIRAC "correct" the response above Schroeder. Not sure if the Denon allows you to dial in such filters manually however.

See the article below for more info:

The Schroeder Frequency: A Show and Tell, Part 1

Even if you live in a studio apartment, you have at least two listening rooms. Well, in a sense. Every listening room is, in essence, two listening rooms when you look at it from the perspective of sound.To midrange and treble frequencies, your listening room is like a billiards table. Like...

www.soundandvision.com

 

[gorman]

A single high shelf filter would probably be a better option to lower the treble, than letting DIRAC "correct" the response above Schroeder. Not sure if the Denon allows you to dial in such filters manually however.

See the article below for more info:

The Schroeder Frequency: A Show and Tell, Part 1

Even if you live in a studio apartment, you have at least two listening rooms. Well, in a sense. Every listening room is, in essence, two listening rooms when you look at it from the perspective of sound.To midrange and treble frequencies, your listening room is like a billiards table. Like...

www.soundandvision.com

LCR is part of a 5.3.4 Atmos system. I'm heavily into multichannel music, hence I need the tonality of surround (Dynaudio) and Atmos (Polk) speakers to be brought in line with the front bed. Doing that manually is frankly beyond my capability.

 

[gorman]

See the article below for more info:

But thanks for the link. I am familiar with the concept (learned here) but I had never read it. Maybe I could experiment a bit. Not sure because what I'm hearing now is so good as to be almost intoxicating, as I've just tried to explain to my family.

EDIT: then again... I'm not excluding the idea that somebody knowledgeable could tell me that my results are crap. Setting aside my listening experience, just looking at the graphs I expected smoother results from 200Hz to 1kHz, considering the amount of treatment on ceiling and floor. But I have no real knowledge about what to expect, so I could absolutely be dead wrong in my expectations, which are based solely on looking at KEF's estimated in-room response here. It could also be that I took MMM wrong (maybe moving the microphone too fast, although I tried not to), I'll soon redo the measurements using the stand with moving boom arm I use to take Dirac measurements, to check if anything significant changes.

 

[Honken]

I wouldn't worry too much about the response over Schroeder. I am not sure what you are using to visualize your measurements but the variable smoothing in REW is a good option for visualizing room responses. To cut to the chase a bit, high Q variations in the measurements aren't as easily (if at all) discerned by your ear as larger deviations from whatever your target are. In other words, don't get blinded by the big spikes - other smoothing options will help you to visualize the actual trend of the frequency response in your room.

I would personally not try to EQ the spikes above Schroeder away, nor would I try to adjust speakers to a target above Schroeder via room EQ.

I am not knowledgeable in DIRAC, but perhaps someone here can chime in whether or not it is possible to add in shelf filters of your to match your taste.

Lastly, what @sigbergaudio mentioned about cutting lower frequency spikes too much is very true. You can't cut the lower frequency spikes too much without impacting overall tonal balance. I do wonder if you truly need to worry about lowering the targete frequency if you simply didn't cut the spikes in the bass area as much.

 

[Heinrich]

Hi, I don‘t recall the measurements for the R7, but wasn‘t it so that the model had some (minor) issues in the midrange smoothness on–axis? And the vertical may show a trough due to interference of the four bass drivers? This might explain the weak upper bass.

What came to me was that DIRAC seems to correct the mids/treble also, but not quite right. And it looks like it fills in dips.

Not the least, the measurements look like they were taken on–axis of the speakers. Anyway, the target looks a bit hot in upper midrange and treble if Harman should be it.

Last, the room treatment. It may be just to much. I never used room treatment, and still live. For some good reason I never felt to use automation for equalizing.

Very last, promised, I never considered to have a home cinema. It may be different with that, but with simple stereo thr Harman is =not= the target, as Dr.Toole says. The Harman is only the result of perfect on–axis combined with perfect directivity in an average room. To take it the other way round, as DIRAC does, doesn‘t make sense, he says.

What I would do:
- measure the frequency response of asingle speaker on listening axis, without room interference
- equalize to flat, no tilt, should be minor adjustments with R7
- chose bass crossover
- integrate bass and the front/center at the listening position, now with room interference
- using dirac, but not allow alterations above 200Hz or so
- further adjust to taste with mild filters, take some time
- call it a day

 

[gorman]

Dirac doesn't work as a parametric equalizer. You cannot apply "mild" filters. You can just provide a target curve and set the range over which the correction has to be applied.

The measurement, at MLP, was 16.5° off-axis for L and R. C is on-axis, as I wrote.

The curve I use is one I've used (with mild adjustments according to equipment, position, etc.) for the past several years.

(R7 has two bass drivers, not four, that's R11)

 

[Heinrich]

Dirac doesn't work as a parametric equalizer. You cannot apply "mild" filters. You can just provide a target curve and set the range over which the correction has to be applied.

The measurement, at MLP, was 16.5° off-axis for L and R. C is on-axis, as I wrote.

The curve I use is one I've used (with mild adjustments according to equipment, position, etc.) for the past several years.

(R7 has two bass drivers, not four, that's R11)

But you can change the target manually? You can measure virtually echo-free by windowing? It is a mystery to my why DIRAC is that successful, commercially.
Now your question is, why isn‘t the target I used many years no good anymore with the R7s? Your initial suggestion was, that the coax-design is the reason for the failing match: „Same target, hence same sound.“

 

[gorman]

But you can change the target manually?

Yes, of course. The target curve is completely customizable.

You can measure virtually echo-free by windowing?

I don't even know what you're talking about.

Now your question is, why isn‘t the target I used many years no good anymore with the R7s?

Hmmm... No? Where did I say that?
I wrote, on this very same page, "what I'm hearing now is so good as to be almost intoxicating, as I've just tried to explain to my family."

At 54, I'm absolutely willing to learn and I'm a firm believer in the scientific approach to audio (and, consequently, painfully aware that my hearing is far from being what it was at a younger age, especially for high frequencies). But I do know what sounds good to my ears. The initial question came when I was using a brighter target curve, hence I was wondering about the possible impact of coaxial drivers on what I was hearing. Once people explained that the culprit was more likely to be the target curve, I modified it (you can check the differences, both have been posted in this discussion) and I liked what I was hearing much more, as I wrote. I listened to music I know for three hours straight before concluding it was sounding good.

Your initial suggestion was, that the coax-design is the reason for the failing match: „Same target, hence same sound.“

I hope the above can better explain the chain of events.
I wouldn't discount the option that I could have messed up MMM on top of the 1/48 smoothing, which from what I've read so far is not representative of how we perceive frequency response. That's why I posted the measurement file too, by the way.

 

[Heinrich]

Yes, of course. The target curve is completely customizable.



I don't even know what you're talking about.



Hmmm... No? Where did I say that?
I wrote, on this very same page, "what I'm hearing now is so good as to be almost intoxicating, as I've just tried to explain to my family."

At 54, I'm absolutely willing to learn and I'm a firm believer in the scientific approach to audio (and, consequently, painfully aware that my hearing is far from being what it was at a younger age, especially for high frequencies). But I do know what sounds good to my ears. The initial question came when I was using a brighter target curve, hence I was wondering about the possible impact of coaxial drivers on what I was hearing. Once people explained that the culprit was more likely to be the target curve, I modified it (you can check the differences, both have been posted in this discussion) and I liked what I was hearing much more, as I wrote. I listened to music I know for three hours straight before concluding it was sounding good.



I hope the above can better explain the chain of events.
I wouldn't discount the option that I could have messed up MMM on top of the 1/48 smoothing, which from what I've read so far is not representative of how we perceive frequency response. That's why I posted the measurement file too, by the way.

Hi, I was referring to your post number 26. Now, as is all right according to the above, have fun!

 

[gorman]

Hi, I was referring to your post number 26. Now, as is all right according to the above, have fun!

I don't see what you refer to on post #26.

BUT I don't "want" this to be good. I'd like for it to be good in a measurable way. Since i have about 95% to learn, as stated, I will read with interest evaluation of the measurements file I posted. While taking another set of measurements tomorrow.

Put it in another way, I'm against deluding myself. If it measures badly I would prefer to know and understand what can I do to make it better. I just lack the skill to understand if measurements taken are good, acceptable or bad.

Hope it's clearer now

 

[Heinrich]

I don't see what you refer to on post #26.

BUT I don't "want" this to be good. I'd like for it to be good in a measurable way. Since i have about 95% to learn, as stated, I will read with interest evaluation of the measurements file I posted. While taking another set of measurements tomorrow.

Put it in another way, I'm against deluding myself. If it measures badly I would prefer to know and understand what can I do to make it better. I just lack the skill to understand if measurements taken are good, acceptable or bad.

Hope it's clearer now

As I said, you may better start with so called anechoic measurements. Today we use so called windowing for this purpose. If DIRAC can‘t do that, I‘m a bit lost.

 

[gorman]

As I said, you may better start with so called anechoic measurements. Today we use so called windowing for this purpose. If DIRAC can‘t do that, I‘m a bit lost.

Not questioning the usefulness of such method (with which I'm completely unfamiliar) but that's simply not the way Dirac approaches correction. It's multipoint measurements in a more or less defined area around the MLP, then set crossovers, a target window, possibly curtains to limit the range of intervention. Calculate. End.

I'll probably do better in asking further clarifications on my results in a Dirac thread.