Speaker vs headphone review target EQ

[Chr1]

Just curious as to why, in reviews the ideal speaker EQ is essentially flat whereas for headphones/IEMs the target EQ is not?

Thanks.

 

[DVDdoug]

I should let someone else answer, but I THINK it's mostly "room effects".

Just curious as to why, in reviews the ideal speaker EQ is essentially flat

A "flat" speaker normally measures flat on-axis in an anechoic chamber. When you put that speaker in a room the on-axis & off-axis sounds bounce around and change the response. And you get the "circle of confusion", since mixing & mastering engineers also don't work/listen in anechoic chambers.

whereas for headphones/IEMs the target EQ is not?

To better-approximate what you hear from speakers in a room (and what the engineers & producers were hearing).

And it is an average preference curve... Different people have different preferences.

 

[Jimbob54]

Ears receive sounds differently in a room with speakers in a triangle from listening position than with 2 little speakers strapped to the side of your head creating their own room.

Is about the extent of my understanding...

In theory, the ideal downward sloping flat speaker curve should sound similar to the headphones that match the Harman headphone eq to most users. With bass shelf level being more of a user preference thing but some additional bass needed above flat.

 

[staticV3]

Just curious as to why, in reviews the ideal speaker EQ is essentially flat whereas for headphones/IEMs the target EQ is not?

Thanks.

We measure speakers using straightforward microphones, which represent flat (as in neutral) sound as a more or less flat line.
We measure headphones using a head and torso simulator which tries to simulate the inner and outer ear and their acoustic impedance.
These simulators represent flat sound as a non flat line.

The fact that we then show this data in its raw, curvy form has actually come under criticism in recent months and it's why you may see some headphone reviewers present their headphone measurements in a so-called DF-compensated form, which makes the data look much more like how people are used to from speakers.

Here's an example: https://global.discourse-cdn.com/bu.../39eb471ccaba0620db9c4d639c10655ce6d227ce.png
You can read this just like you would the in-room response of a pair of loudspeakers

 

[Chr1]

OK. I am still confused. I get that with speakers it is good to have a flat response. Then you deal with the room.

Is the preferred ideal headphone EQ curve a general average preference ie. subjective?

Thanks again.

 

[somebodyelse]

First part of 3 which covers it fairly well - the introduction will tell you what is in the others, with links.
https://www.headphonesty.com/2020/04/harman-target-curves-part-1/

 

[staticV3]

Is the preferred ideal headphone EQ curve a general average preference ie. subjective?

The headphone target that we currently use (Harman OE2018) was created by measuring Harman's reference room (reference speakers and acoustics) with a head and torso simulator, then taking the resulting curve and letting both trained and untrained listeners fine-tune the bass and treble.

It is therefore a combination of objective data and subjective preference, and clearly labeled as preference target. A target that is statistically preferred among a diverse group of listeners.