Is flat frequency response a hoax?


I have seen a number of speaker companies claiming that their design has a ruler flat response. They then proudly display a graph with a flat line as if it's an indication of its superior quality. Poppycock.

Flat response is a myth. Everybody has different hearing so there's no reason to expect that there would be a one size fits all frequency response.
We don't all wear the same sized shoes do we? Everybody has different sized feet. 

There are plenty of flat response speakers that sound horrible. I've heard quite a lot. There are many non ruler flat great sounding speakers too.
Do not be duped by this hogwash. 

If the mixing engineer used a pair of speakers that is 3db down in the mids and top end then he may have boosted that region by a similar amount. Now when the track gets played on a ruler flat speaker it sounds too bright. So as you can see, a flat response is useless.







kenjit
Given that imperfection in replicating a live performance from a recording is inevitable, one might ask what the next best thing would be, within whatever constraints are imposed.

And, what yardstick should we use to evaluate how well we are doing in our pursuit of "the next best thing"? Is it frequency response, waveform fidelity, subjective preference, or some weighted average of many factors?

My personal belief is that it is subjective preference, that some things matter more to the ears than others, and that we should juggle the inevitable compromises accordingly. In other words, I believe the goal is the closest possible recreation of the PERCEPTION of hearing live music, within whatever constraints we have.

If "what matters most" becomes "what matters most to the ears", then the answers inevitably involve psychoacoustics.

So getting back to the topic at hand, flat frequency response has not been found to be subjectively preferable in controlled blind listening tests. A "flat" measured response has been found to sound like the top end is tipped up too much, while a gently downward-sloping frequency response has been found to SOUND LIKE it is actually "flat".

Imo "sounds like it is flat" would be an appropriate goal, rather than "actually measures flat", at least for home audio (the goal posts are in a different place for studio monitors). This is not the only thing that matters of course, but I think it’s one of them.

Duke
Can anyone provide the name of a speaker company that claims ‘ruler-flat’ frequency response?
The company is Rulerflat  speakers but they dont exist anymore... :)
Phase shift vs frequency would also be useful in addition to frequency response.  Impedance vs frequency might also suggest what is happening with the phase.  Two speakers might have identical flat response vs frequency, but sound very different because of phase shifts (different harmonics summing).  Still, all measurements are useful.

https://www.stereophile.com/content/measuring-loudspeakers-part-one-page-6
"Can anyone provide the name of a speaker company that claims ‘ruler-flat’ frequency response?"

Neumann studio monitors come to mind. See data for the KH-420:

https://en-de.neumann.com/kh-420#technical-data
 
Duke