Most people are looking for "flat"

nelsress

nelsress

AK Subscriber
Subscriber
which I understand, conceptually, but often wished my high end audio equipment allowed me to "unflatten" the sound a bit. Apparently this concept of flat being ideal is much older than I ever imagined as I was reading an article in the November 1946 edition of Radio Craft and this same idea was referenced.

The reason I'm broaching this topic as I thought the explanation for the whole concept of perfectly flat equipment put into words my thoughts far better than I have been able to up to this point.

The author cites all of our individual psychologies as a foremost consideration due to our tastes and desires which are not only different from person to person but also different from program source to program source. He goes on to say that it follows that our amplifiers need to be equipped with a means of varying its response curved, preferably with independent bass and treble controls.

Then he says, "It is often stated (and rightly so, if the statement is qualified) that a flat amplifier is ideal. If we had a flat microphone, a flat amplifier and a flat speaker, located in a perfect acoustic chamber, and if the speaker output were exactly as loud as the source, the system would indeed be ideal." This makes sense to me, I have to think (or is it hope) that it does to others as well?

He goes on to point out that even with such a "perfect" sound system, if we turn the volume down to half of the sound source that it would no longer sound like the original due to our introduction of a new variable, our ears! Apparently the human ear's response curve varies with volume-in other words, the lower the volume the less our ears are capable of hearing both the highest and the lowest of frequencies.

The article then goes on and addresses room acoustics as an important variable, and points out that the most disturbing element or variable in any system as being distortion.

Anyway, I found it to be a very interesting article and one that I'm using to help design a good (or better, hopefully) pair of enclosures for a pair of coaxial drivers I'm going to experiment with and just thought I'd throw some of these ideas/concepts out there and see if anyone else agrees, disagrees or would like to add anything further.
 
Register to hide this ad
Not to worry, I'm not, I just found it interesting, especially that the idea of flat being so often being the goal, being something that was talked about as far back as in the forties.
 
I think you'd want components that were as flat as possible so as to not add their own "color" to the signal. However, that's different from listening to music with - for example - a bump in certain frequencies using a tone control, eq, etc., to suit your tastes or the music you're listening to. Still, zeb is right - listen for YOUR enjoyment.
 
The Fletcher and Munson curve was an observation, not a prescription.

One of the long standing debates in audio is whether compensation for lower listening levels is "legitimate".

One side says the perceived frequency response should be the same for lower listening levels as for high levels, so the low and high end frequencies should be boosted at low listening levels to get a perceived flat response.

The other side says flat is a source attribute and how you hear it at lower levels is the way it is supposed to sound; boosting the low and high end makes it sound unnatural because one is over-riding the way the ears actually work. The usual argument is that a band heard from a distance is going to have reduced perceived frequency extremes, so lower volume listening should sound like that, too.

Way back then, the frequency range for really good systems was something like 80Hz - 12KHz, so the issue was more theoretical. The modern expectations tend to be with reference to the 20Hz - 20KHz range... that additional extension has tended to warm up the Fletcher and Munson debate because now it is possible to provide compensation for gear that can provide those frequencies. The popularization of the electric bass in the last 60 years has been a huge factor as well.

The F-M curve has been adjusted with subsequent research, the latest corrections are only a few years back... the original curve appears everywhere but it is outdated.
 
Last edited:
What's flat?

During the heyday of Advent speakers, Consumer Reports dinged them because their output, measured in a anechoic chanber was not "flat". Henry Kloss responded, pointing out that they were intentionally designed to compensate for the room acoustics in the standard suburban living room. In that environment, Advent speakers approached flat.

The dimensions of my home theater were carefully selected to optimize the sound. The carpet and acoustic tile ceiling were deliberate choices. I have added room treatments as well. It's the best sounding room that I have had in a home. Still, running Audyssey that does both frequency and time correction noticeably improves the sound. While I understand the purist's point of view of not placing electronics in the signal path that may introduce phasing and other non-linear errors, I sometimes think they are willing to accept gross errors to avoid possible small errors. It's like straining at a gnat and swallowing a camel.
 
Listen to live music in a reverberant space (e.g., a choir, a capella, in the nave of a stone cathedral); listen to live music in a dead space (a folksinger with an acoustic guitar in a small space with drapes on the walls, thick carpet on the floor) and compare the sound -- and -- compare which kind of sound one prefers. De gustibus non est disputandum.
 
"Flat", to serve accurately reproducing the recording.
Turning it into some sort of sonic thrill ride is something quite different. This is part of the critisizm of the Bose direct/reflected notion where it's a creation of what never was, rather than reproduction of what was recorded, including the environmental information if that applies.

Sent from my SM-N900V using Tapatalk
 
From a recordists perspective, I've recorded flat, and heard flat.
Flat is a near-field response characteristic that isn't entirely desirable in the diffuse-field live music recording venue. To achieve something closer to a flat response in the recording, having something that doesn't lose it in the first place helps. So, having something that is open and accepting of the fragile highs helps a lot in preserving them in the end.

So, with that said,... a live recordist dream response.
the frequency response plots of a stereo matched pair of diffuse field, wide-cardioid mics:
DSCN0049.jpg


With the exception of the highs preserving hump, they're pretty dang flat down to the chest thumpers.
 
Frank Sol said:
I would bet... No one here has heard a 'flat' live music presentation
Click to expand...


It ^ looked good when I posted it :smoke:

What I meant to say and it still may not make sense. Live music venues if tested are not 'flat' listening environments. Wherever you're sitting or standing may have dips and rises across the audio band. Therefore what you are hearing (music) is not what is meant technically to be heard
 
mfrench said:
From a recordists perspective...a live recordist dream response.

With the exception of the highs preserving hump, they're pretty dang flat down to the chest thumpers.
Click to expand...

Excellent info, clearly transmitted and perfectly understood. Thanks for your unique perspective.
 
You must log in or register to reply here.
Back
Top Bottom