Frequency Response of Speakers

[j_garcia]

Flat frequency response does not necessarily correspond to perfect reproduction of the original signal. If you use the x-over design to attenuate the speaker's response to achieve a flat response, that means the signal has been modified. The sound produced is also colored by the overall speaker design - driver selection, materials, cabinet design and tuning, x-over design, etc...

Accuracy and personal preference are two very different things, and as I mentioned before, just because a speaker is accurate or flat, does not mean you will like the way it sounds.

I could use $20 worth of parts and potentially build a speaker that was nearly flat across it's range. Would that make it the best speaker in the world? Hardly. It is those variances in the speaker's characteristic sound that make you like or not like the way a particular speaker sounds.

 

[MacManNM]

Flat frequency response does not necessarily correspond to perfect reproduction of the original signal. If you use the x-over design to attenuate the speaker's response to achieve a flat response, that means the signal has been modified. The sound produced is also colored by the overall speaker design - driver selection, materials, cabinet design and tuning, x-over design, etc...

Accuracy and personal preference are two very different things, and as I mentioned before, just because a speaker is accurate or flat, does not mean you will like the way it sounds.

Whoah gear down there big shifter........

Assuming all other things equal, phase, distortion etc, there is no way what you say is true. If the speaker is flat throughout its intended usage range it is going to reproduce the signal EXACTLY as it was recorded.

 

[Shaft0rz]

This is the same debate that goes on for instrument amplifiers/cabs. I'm a bass player, and there are some highly regarded amps and cabinets that are anything but flat. Ampeg equipment sounds great, but it adds a great deal of coloration to the sound. Some people see that as "color" or "character" and they enjoy it. Other speakers, like the Acme Low B2 (http://www.acmebass.com/) are "hi-fi" sounding with a reasonably flat response from 41hz-22khz (and only -6db down to 31hz), are also highly regarded, even though they don't impart as much coloration. Some don't like them because they sound too "flat" for their ears.

While its not a direct comparison (you don't want your stereo speakers to add as much color as an instrument speaker), I think the lesson is the same. Coloration and a non-flat frequency response doesn't have to be a bad thing, it can be euphonic.

It may be cliche, but I think it all comes down to the ear listening.


PS- Also worth throwing into the mix (no pun intended) -- hyper-accurate studio monitors aren't always the best things to listen to music on. Perhaps it's a result of most recordings being over-mastered to compensate for most speakers.

 

[j_garcia]

If you are attenuating the response of the drivers to hit a flat response, then this would affect the resulting sound would it not? (I'm asking, not saying this is fact) And once again the sound will be altered by the driver's characteristics.

OK, speaking theoretically, if you had a speaker that had perfectly flat response, thus reproducing the signal 100% faithfully, would it sound exactly like original or would it still be colored by the speaker?

 

[ironlung]

Again all other things being equal speaker 1:

Or speaker 2:

If all things are equal isn't speaker 1 adding things to the recording that are not there? If all is equal I'll take the flat response.

 

[j_garcia]

It's easy to say that looking at a graph, but listening to those two speakers is a different matter.

 

[MacManNM]

If you are attenuating the response of the drivers to hit a flat response, then this would affect the resulting sound would it not? (I'm asking, not saying this is fact) And once again the sound will be altered by the driver's characteristics.

OK, speaking theoretically, if you had a speaker that had perfectly flat response, thus reproducing the signal 100% faithfully, would it sound exactly like original or would it still be colored by the speaker?

It doesn't matter if you have to artificially attenuate the drivers, as long as it is linear. As far as the drivers characteristics, as long as you are applying some sort of linear equalization, they would idealy be transparent. So if indeed it was flat, there would be no coloration. Now to make this scale linear with power is not really that easy, then you really have to think about compression and driver characteristics. Idealy one would use a computer to actively correct for amplitude, phase, and frequency as you were listening.

 

[j_garcia]

Have you listened to speaker 1 and 2? Will there be an outcome to this thread? >waiting for bomb to drop<

 

[ironlung]

This is the same debate that goes on for instrument amplifiers/cabs. I'm a bass player, and there are some highly regarded amps and cabinets that are anything but flat. Ampeg equipment sounds great, but it adds a great deal of coloration to the sound. Some people see that as "color" or "character" and they enjoy it. Other speakers, like the Acme Low B2 (http://www.acmebass.com/) are "hi-fi" sounding with a reasonably flat response from 41hz-22khz (and only -6db down to 31hz), are also highly regarded, even though they don't impart as much coloration. Some don't like them because they sound too "flat" for their ears.

While its not a direct comparison (you don't want your stereo speakers to add as much color as an instrument speaker), I think the lesson is the same. Coloration and a non-flat frequency response doesn't have to be a bad thing, it can be euphonic.

It may be cliche, but I think it all comes down to the ear listening.


PS- Also worth throwing into the mix (no pun intended) -- hyper-accurate studio monitors aren't always the best things to listen to music on. Perhaps it's a result of most recordings being over-mastered to compensate for most speakers.

I would like speakers in my HT to exactly reproduce the coloration and character in the amp/cabinet combo you use on your bass to get as close to being at the show live in my HT. Wouldn't that need the flatest speaker response possible to reproduce the recording exactly?

 

[MacManNM]

Have you listened to speaker 1 and 2? Will there be an outcome to this thread? >waiting for bomb to drop<

I have listend to one of them and a friend listened to the others, really wierd, his comments were dead on with the FR of the speakers, he listened to #1, said that they lacked bass, were a little weak in the midbass, had good midrange and decent highs. The imaging was average. He said that they were nothing special. I listened to #2, thought they were pretty good, detail was really good as was imaging.

 

[MacManNM]

This is the same debate that goes on for instrument amplifiers/cabs. I'm a bass player, and there are some highly regarded amps and cabinets that are anything but flat. Ampeg equipment sounds great, but it adds a great deal of coloration to the sound. Some people see that as "color" or "character" and they enjoy it. Other speakers, like the Acme Low B2 (http://www.acmebass.com/) are "hi-fi" sounding with a reasonably flat response from 41hz-22khz (and only -6db down to 31hz), are also highly regarded, even though they don't impart as much coloration. Some don't like them because they sound too "flat" for their ears.

While its not a direct comparison (you don't want your stereo speakers to add as much color as an instrument speaker), I think the lesson is the same. Coloration and a non-flat frequency response doesn't have to be a bad thing, it can be euphonic.

It may be cliche, but I think it all comes down to the ear listening.


PS- Also worth throwing into the mix (no pun intended) -- hyper-accurate studio monitors aren't always the best things to listen to music on. Perhaps it's a result of most recordings being over-mastered to compensate for most speakers.

Yes but you are creating the music, not reproducing it. That application is totally preference driven.

 

[MDS]

So if indeed it was flat, there would be no coloration. Now to make this scale linear with power is not really that easy, then you really have to think about compression and driver characteristics. Idealy one would use a computer to actively correct for amplitude, phase, and frequency as you were listening.

I think that sums it up nicely. Given the choices presented I would choose the speaker with a flat response. It is accurate.

I don't understand the logic that says a flat response doesn't necessarily sound good and it's better to just listen and choose the speaker that sounds best to you in your room - that is choose the speaker that is inaccurate yet colors the sound in a way you find pleasing.

The flaw I see in that reasoning is that it puts the cart before the horse. The acoustical flaws of your room affects the sound so you want to choose a speaker whose own flaws counteract the room acoustics? Doesn't make sense to me. It seems it would be better to get the speaker that is the most accurate and address the external factors in other ways (eq, room treatments, etc). Otherwise, it's nothing but trial and error buying multiple speakers till you hear what you want. Make changes to the room and all bets are off and you are right back where you started.

 

[MacManNM]

I think that sums it up nicely. Given the choices presented I would choose the speaker with a flat response. It is accurate.

I don't understand the logic that says a flat response doesn't necessarily sound good and it's better to just listen and choose the speaker that sounds best to you in your room - that is choose the speaker that is inaccurate yet colors the sound in a way you find pleasing.

The flaw I see in that reasoning is that it puts the cart before the horse. The acoustical flaws of your room affects the sound so you want to choose a speaker whose own flaws counteract the room acoustics? Doesn't make sense to me. It seems it would be better to get the speaker that is the most accurate and address the external factors in other ways (eq, room treatments, etc). Otherwise, it's nothing but trial and error buying multiple speakers till you hear what you want. Make changes to the room and all bets are off and you are right back where you started.

Bravo! I agree. This is what McIntosh used to do (still might) and the results are exceptional. My grandfather has his 2ch system (86 yrs old still loves his music) it is all McIntosh and the guys came in in 1978 and set it all up using noise generators, spec anns and calibrated mics, it hasnt been touched in 27 years and still sounds absolutely wonderful.

 

[WmAx]

Not fair! You just can't go around asking such things MacManNM! Clearly, what sounds good to one person sounds awful to another.

Is the question 'accuracy' (as I thought), or 'preference'?

Regards

Listern preference is demonstrated to be nearly always identical among different people, given a (1) controlled environment/setup (2) the same program material, and (3) non-impaired hearing. People will overwhelming choose the same sound as has been demonstrated in peer-reviewed, credited [1]scientific study.

-Chris

[1] Loudspeaker Measurements and Their Relationship to Listener Preferences: Part 2
Floyd E. Toole
JAES, May, 1986, Vol. 34, pages 227-235

 

[WmAx]

If you are attenuating the response of the drivers to hit a flat response, then this would affect the resulting sound would it not? (I'm asking, not saying this is fact) And once again the sound will be altered by the driver's characteristics.

OK, speaking theoretically, if you had a speaker that had perfectly flat response, thus reproducing the signal 100% faithfully, would it sound exactly like original or would it still be colored by the speaker?

A transducer behaves/models almost perfectly as a minimum phase device. As such, the coloration(resonance) caused by a frequency response deviation is correctable by eliminating this deviation via a corrective filter circuit, for example. As Mac suggests, however, you must also account for driver physical performance[for example having to boost a band by a large degree may cause the speaker to operate at SPL levels where the motor can not remain linear due to the excursion/incursion and power levels required].

-Chris

 

[j_garcia]

If you want to know the funny part. My speakers have a response of +/-1.2dB across their range I didn't compare the response curves though, just listened to them. It just so happened that the ones I prefer were extremely flat.

Curve (though it only shows fro 200Hz-20kHz).

 

[Shaft0rz]

Yes but you are creating the music, not reproducing it. That application is totally preference driven.

Good point -- the goals are different in each case. I'd argue though, that they're similar than you might think. Proponents of hi-fi, accurate, flat speaker cabinets believe that all the character and color in their sound should come from the instrument itself, not the speaker it's attached to. The same thinking holds for music -- if you believe that all your coloration and character should come from the music source (cd, vinyl, dvd), you want a flat response, and some people enjoy that sound.

If on the other hand you view your speakers as a part of the listening experience itself (or in the case of instruments, you consider it part of your "sound"), you don't want a flat response.

I tend to fall in the second half -- I like tubes, which color the sound, and I like speakers which impart some gentle coloration. I find listening to studio monitors to be a bland (albeit impressive from a technical standpoint) experience.

After re-reading this, I realize I suck at being clear in my posts

 

[mtrycrafts]

Do you think the ability of a speaker to produce a flat frequency response curve (measured) illustrates a speaker’s ability to reproduce music more accurately? IE, one that is flatter across the spectrum is going to sound better?

Edit:
Assume that distortion and phase measurements are of the same quality. This is meant to be

Speaker A(flat) VS Speaker B (not flat)

I believe what credible research is telling us:
http://www.harman.com/wp/pdf/AudioScience.pdf

Yes, flat frequency response and off axis response must follow as well.
DBT listening tells us this is what is needed.

 

[mtrycrafts]

Frequency response dosen't mean jack if the distortion measurements are high. Also that speaker the plays perfectly flat will sound like poo once it's put in a room. You want a speaker who'se FR plays well with your room modes.

http://www.harman.com/wp/pdf/AudioScience.pdf

 

[Sheep]

Mac,


This poll is almost useless. If the speaker is perfect in everyway, but one has a flat FR, and the other doesn't, what would I choose? I wonder what.


you have to have more variables in the question. For my personal opinion, No, flat FR isn't everything for me.

Sheep