Flat Response

[Zilch]

Re: Flat Response

"High Fidelity" was, and remains, about the *reproduction* of sound from one environment in another. It's not limited to one "genre" of music.

Used to be, which is why AR's LVR side shows convinced the public, ignorant of the distinction, that AR3a's (and thus, ARs in general) were "accurate" loudspeakers. They aren't, any more than headbanger delight JBL L100s with their boomy bass, "forward" midrange and (incoincidentally) rolled-off highs are. I have difficulty rationalizing adulteration of the source with linear distortion in its reproduction in the interest of "realism" as "high fidelity" without this qualification.... :rolleyes:

http://en.wikipedia.org/wiki/High_fidelity

[Guest]

Re: Flat Response

You misrepresented my position.

Calling it a subjective choice is to denigrate the validity of the choice.

This very much reads like a generalization (ie "they"), painting all who have found through study that non-flat targets can be more accurate as being without measurement acumen or knowledge:

it sounds fine....unless your conceding that a early bass roll off requires a non flat response elsewhere??....

So let me see if I have this right. First, audio reviewers opinions are meaningless and biased (your oft stated position)...it seems unless they agree with you. OK, noted.

But weren't you the one who said that a good speaker should be room agnostic? So, the only answer in your mind must be that I can't judge good sound. As a debating approach, its lazy, mean-spirited and baseless.

Dave

You misrepresented my position. What's your problem?

Dennis,
Count me as one dissenting opinion

I think you always need to deviate from flat

As I've stated flat response is not my ideal

;)

Let's agree to disagree about needing source on axis amplitude distortion.

[Guest]

Re: Flat Response

You misrepresented my position. What's your problem?

"Flat response" sells (to the ignorant)

Ok ;)

[Dennis H]

Re: Flat Response

Any questions now Dennis?

No, I thought my last paragraph agreed with Dave and Deward's points although maybe I didn't stress it enough.

Now, if you don't have all of those, you may need to compromise one to make one or more of the others better. That's where you have to start using your ears.

If the in-room stuff (ears) isn't working like it should, you may need to sacrifice flat on-axis response. That's the whole basis of the 'room correction' algorithms that all the receivers have these days.

[Guest]

Re: Flat Response

No, I thought my last paragraph agreed with Dave and Deward's points although maybe I didn't stress it enough.

How about the 5th group, which is:
Design the acoustic source with as linear on axis as possible and as linear off axis as possible, then place it in a reverberant room.
If you find the need to apply amplitude adjustment at the listening positions/area to correct tonal balance, based on that particular room, do so then.
I fall into that group ;).

How does your statement differ from mine?

If the in-room stuff (ears) isn't working like it should, you may need to sacrifice flat on-axis response. That's the whole basis of the 'room correction' algorithms that all the receivers have these days.

Yes, "Room" correction, after the fact, not "design into the source" as D&D advocate. There is no way to know what "correction" will be needed, if any.
The "non-flat" should be applied in room per specific case, if needed, not as a design feature, unless that design feature is for you only. That is not what D&D advocate.

cheers,

AJ

[dantheman]

Re: Flat Response

"High Fidelity" was, and remains, about the *reproduction* of sound from one environment in another. It's not limited to one "genre" of music. The difference now is that most "music" has no "original" sound . . . it is created electronically or in studio, and then "produced" in different environments, including "concerts" and living rooms. "Live" recordings of rock concerts are not done with a pair of mics hung over the stage, like a symphony recording might be (and the rock audience hears nothing "live" or "natural" . . . they hear loudspeakers) . . . they are multi mic (and multi instrument) feeds blended at the mixer for distribution in a different environment. There is no "standard". And particularly there is no such thing as "flat" . . . every channel on the board is compressed, limited, reverbed, equalized and faded in and out to suit whatever the engineer and producer (and sometimes the artists) think their audience wants, from the speakers they have. "Concert hall realism" at least has an external standard . . .

+1 on that. They definitely aren't trying and essentially can't do realism. Trust me, they go for some arbitrary goal depending on genre that basically boils down to "what this demographic buys". I read an article that touched on it a few months ago.

Dan, have you tried equing the response above 8kHz? Do you think that differences in the curves above this frequency may have some part to play in the perceived brightness? Personally I have never found >8kHz added harshness but it can add some tizz.

Thanks for the graphs.

No, never really to EQ it really. I have played with the treble knob to graph its effects and listened to how the changes sound, but I don't currently have means to narrow down that top octave.
I don't think that area has anything to do with the perceived brightness. Like you it seems to mostly be just tizz or atmosphere or something, but not a lot of it. The thing that seems like brightness(a subjective term that has no definite definition) to me seems more like 2-10kHz--the presence region and above where the ear is sensitive. So far, the only thing that I can remotely connect a harshness to is diffraction.
This cone/dome 2-way didn't sound harsh to my ear either. Though not as smooth as the Mackie 624mkII or the Behringer 1030A.

[DDF]

Re: Flat Response

How does your statement differ from mine?


Not just at HF, but LF. The "non-flat" should be applied in room per specific case, if needed, not as a design feature, unless that design feature is for you only. That is not what D&D advocate.

cheers,

AJ

Please refrain from stating my position because you continue to get it wrong, and its getting tiresome. I PRECISELY said you should deviate from flat response on axis to tune for the particular room sound, where needed.

You slandered me me in the past when you were banned and now you continue to misrepresent everything I write.

Just back off.

[Guest]

Re: Flat Response

This cone/dome 2-way didn't sound harsh to my ear either.

I see no reason why it should, with that HF power/smooth decrease away from axis. That mid coloration ought to be obvious though. Up front, flat, without much depth imaging?

cheers,

AJ

[Deward Hastings]

Re: Flat Response

The "non-flat" should be applied in room per specific case, if needed, not as a design feature, unless that design feature is for you only. That is not what D&D advocate.

Don't be deliberately obtuse.

"Flat on axis" works with non-constant directivity tweeters and/or absorbant (or "treated) rooms *if* the combined directivity and hf absorption produces a substantially falling power response as frequency rises. The listener hears a non-flat (falling) combined response overall. If the flat-on-axis speaker has a constant directivity high end and/or is used in a relatively "live" room the listener hears a "bright" or sometimes "harsh" combined response. To compensate such speakers generally require a non-flat (downward sloping) response overall . . . and that situation is more common (more normal) than dead rooms which sound good with simply "flat-on-axis".

And I've given three examples of significantly different but more-or-less "constant directivity" speakers that sound(ed) significantly better in my more-or-less-normally-live listening room with a falling on-axis response . . . the MG3 (ribbon tweeter), the B2030A (easily corrected with the HF cut switch), and ORION+ (now corrected with the 3.x modification).

"Flat-on-axis" can sound OK *if* you have a beaming tweeter and a relatively dead room (lots of HF absorption), since the falling power response results in a falling response overall for the listener. "Flat-on-axis" in and of itself is not a good design goal, since it will, more often than not, not produce a "balanced" or "natural" sound for the listener in the typical listening room. How far off "flat" one should design for depends on the speaker's directivity (power response) and the acoustics of the intended listening room. While "flat" is perhaps an "interesting" place to start it will rarely be the final response of a well designed speaker system. It just won't sound good, most of the time.

[dantheman]

Re: Flat Response

Pretty much dead on AJ my subjective interpretation.

Dan

[DDF]

Re: Flat Response

No, never really to EQ it really. I have played with the treble knob to graph its effects and listened to how the changes sound, but I don't currently have means to narrow down that top octave.
I don't think that area has anything to do with the perceived brightness. Like you it seems to mostly be just tizz or atmosphere or something, but not a lot of it. The thing that seems like brightness(a subjective term that has no definite definition) to me seems more like 2-10kHz--the presence region and above where the ear is sensitive. So far, the only thing that I can remotely connect a harshness to is diffraction.

I find brightness is really a 4 or 5 to 8 kHz problem, similar to your findings.

A main cause of harshness IME is tightly spaced frequency response peaks and dips causing a very uneven frequency response.

Auditory roughness is caused by amplitude modulation and beating. I wonder if excess treble energy out of balance in the reverb field and too hot could be causing roughness when it interacts with the main axial signal.

Dave

[DDF]

Re: Flat Response

Don't be deliberately obtuse.

"Flat on axis" works with non-constant directivity tweeters and/or absorbant (or "treated) rooms *if* the combined directivity and hf absorption produces a substantially falling power response as frequency rises. The listener hears a non-flat (falling) combined response overall. If the flat-on-axis speaker has a constant directivity high end and/or is used in a relatively "live" room the listener hears a "bright" or sometimes "harsh" combined response. To compensate such speakers generally require a non-flat (downward sloping) response overall . . . and that situation is more common (more normal) than dead rooms which sound good with simply "flat-on-axis".

And I've given three examples of significantly different but more-or-less "constant directivity" speakers that sound(ed) significantly better in my more-or-less-normally-live listening room with a falling on-axis response . . . the MG3 (ribbon tweeter), the B2030A (easily corrected with the HF cut switch), and ORION+ (now corrected with the 3.x modification).

"Flat-on-axis" can sound OK *if* you have a beaming tweeter and a relatively dead room (lots of HF absorption), since the falling power response results in a falling response overall for the listener. "Flat-on-axis" in and of itself is not a good design goal, since it will, more often than not, not produce a "balanced" or "natural" sound for the listener in the typical listening room. How far off "flat" one should design for depends on the speaker's directivity (power response) and the acoustics of the intended listening room. While "flat" is perhaps an "interesting" place to start it will rarely be the final response of a well designed speaker system. It just won't sound good, most of the time.

Thank you!

[MSaturn]

Re: Flat Response

Actual response is always totally chaotic - see the orion graphs posted. I don't think peaks/dips cause harshness.

[Guest]

Re: Flat Response

"Flat-on-axis" in and of itself is not a good design goal, since it will, more often than not, not produce a "balanced" or "natural" sound for the listener in the typical listening room.

You have absolutely no basis to claim this, only your subjective experience and maybe a few others. There is no way for you to claim that "more often than not", a flat, undistorted on axis source will sound incorrect in a "typical room". On what evidence?
The opposite is true for nearly every manufacturer that does perceptual research and must sell to the "typical living room buyer", like Harman, Genelec et al.
That is precisely why their designs are "flat" on axis with smooth decreasing off axis. They leave it up to the end user to apply correction (via, eq recommended, not "treatment")...if needed.
"Correction (FR)" after the fact, once you determine the necessity...or not.

[DDF]

Re: Flat Response

I don't think peaks/dips cause harshness.

They absolutely do in the direct sound, as shown in DBT tests with headphones or a mono speaker. 200 trial subjects in my old lab can't be wrong.

Whether reflected off axis ones do or not, now that i think about it, maybe not. I have a rear facing tweeter with my TV set up and there's no harshness.

Dan's probably on the right track with diffraction being a harshness cause since typical baffle diffraction is minimum phase at one point in space: very low delay and causes peaks & dips if not well controlled.