Flat frequency response

Duke is 100% correct. Downward sloping in room which could still be flat/pretty flat at the speaker is perfect. 

@cdc Wrote:

Flat frequency response

JBL engineers speak about flat frequency response in monitor speakers. They believe it should have uniform on and off axis frequency response both horizontally and vertically at all angles. 😎 See article below:

Mike

https://www.xlrtechs.com/dbkeele.com/PDF/Keele%20(1981-05%20AES%20Preprint)%20-%20Monitor%20Loudspeaker%20Systems.pdf

Really excellent, thought provoking ideas.

audiokinesis

1. The in-room response at the listening position dominates perceived tonal balance, and the most natural-sounding in-room response has a gently downward-sloping trend as we go up in frequency.

Yes. I remember Thiel wanted to keep flat and while some people liked them, I thought too bright. I suppose room and components could come into play.

asctim

It really is difficult to get a speaker to simultaneously have a flat, smooth on-axis response while also having a smooth but downward tilted response off axis at all angles.

Hhmmm, that is a good point.

ditusa

They believe it should have uniform on and off axis frequency response both horizontally and vertically at all angles.

Hhmmm, that is a good point too.

newbee

when you refer to flat frequency response are you referring to the sound level at the listeners position, or say 3 ft from the speaker?

Haha, good observation. I have been measuring from 3 ft away and also 9 feet away listening. The 3 feet is an attempt a what the speaker really does. 9 feet is the speaker + room. My personal taste is the speakers measures flat through most of the treble so it will have the downward slope at the listening position since the HF rolls off fast.

I’ve had the opportunity to listen to some speakers lately and what I have taken away is the variety in how speakers are voiced. Maybe the designer will voice the speaker to 1) his taste or 2) what he thinks is most popular and will sell the most. It’s a tough balancing act. While the basic sound quality is often excellent, it’s frustrating to hear some frequency variations that don’t suit my taste.

What I see as obviously wrong, and maybe(?) we can all agree on, I made a speaker and was playing with EQ. Depending on EQ, I was shocked to find the singer didn’t even sound like the same person. They both can’t be right.

where would like. to measure the "flat" response? In your room in an acoustical chamber, in a large/small room. 

I can hardly imagine all speakers sounding the same if equalized to flat.  It's how a speaker releases its notes that gives it its own distinctive sound, whether you enjoy it or not.  Room reflections and acoustics are, of course, important.

But speakers in rooms are usually far far from perfect. The first thing to musical bliss is taming the bad bass nodes and room issues, and if the speaker is contributing to that it gets corrected as part of the process. With a tiny bit of lowering excessive spots in the upper bass and some high treble my goal is the very flattest response in room in my chair from 31Hz up to 12Khz (usually +-2dB). And that's no sub. Taking the irritating bass bump 80-160 from the Raidho D2s is a very good thing. After that it's liquid music in your ears, and a flat response.

Taming the room and speaker into a nice flat response allows the true beauty of the sound to come through. The additional clarity and tight bass is a no brainer. Those who still disrespect any room correction may never have tried with the right unit. I'd never go back.  DSP gives me far better sound, always.