speaker drivers: flat frequency response does NOT mean good sound quality

[wesayso]

@Dave Bullet: you might want to read the thread: Fixing the Stereo Phantom Center
That should give you some pointers as to the why.

 

[mark100]

Quality can be subjective. Accuracy is not. Quality in my definition goes beyond reproduction (accuracy) and into perception.

Accuracy means reproduction of source - in amplitude, phase and with the same recorded distortion.

Quality takes accuracy and adds in room effects and listener location and preferences. The equal loudness curve is included here then we overlay that with personal preference.

Both accuracy and quality are affected by the recording. If the recording is peaky in a sensitive frequency range or full of distortion, then we perceive this as poor quality - even through an accurate pair of speakers.

My goal these days is to build a pair of speakers that makes everything sound good. ..........

I very much like your depiction of accuracy and quality, and I agree with the ultimate goal of quality.

My way of addressing those two is to do everything possible to get my speakers as accurate as possible (reflection free).
And then, as an overlay, be willing to do whatever for quality.

Best method i've found for that so far, is to put individual volume controls on the 4 pass-bands of my 4-ways. The 4 volume controls can be set individually, and all controlled collectively with a master volume control.
Not much source material I can't make sound good with that........

I know astute readers will say I'm screwing up acoustical crossovers with that setup, but that is not the case.
All passbands, each about 2-3 octaves wide, are at flat zero degree phase, so no holes occurs with level offsets.
I don't care where final freq response goes to adjust things, but I find timing shouldn't ever vary.

Besides giving room to make things sound good, it also shows me how crazy different source material is...to the point I think it is impossible to expect a system that can't be adjusted on the fly, to be able to handle the diversity.

 

[plasnu]

Yep, accurate flat response is the best starting point, and it will always be a reference point, but it is not the ultimate goal, imo.

 

[scottjoplin]

Tone controls are handy

 

[Dave Bullet]

@Dave Bullet: you might want to read the thread: Fixing the Stereo Phantom Center
That should give you some pointers as to the why.

thank you for that. an interesting read and explains one flaw with my approach.
I've been doing single speaker listening testing with left or right stereo signals (of course I have the measurements to back up changes and initial design choices).

I have both boxes now ready to go and enough parts for a full (currently target) xo to be listened to.

I have my tracks that are harsh - so they will be my first test subjects.

I very much like your depiction of accuracy and quality, and I agree with the ultimate goal of quality. <snip>

My solution to this has been to use a Raspberry Pi based music streamer with hat DAC and have a "learning EQ" by folder level (could make it more granular). I can then choose the EQ I want to apply for the few masterings that are peaky - and the music player loads the correct EQ or"flat profile" if none saved.

That way I can "learn" as I play through my collection just by pressing the EQ I want the player to load next time.

Works very well.

 

[Galu]

Tone controls are handy

In my audio universe they are indispensable!

 

[kinsei]

This thread is about your misconception about drivers and speaker design. Your misconception is based on reading (and not comprehending) only one book on loudspeakers, on accepting Quora and speaker design notes (largely marketing technobabble) as your source of knowledge... and nothing else! Oh, do not forget your wrongly defined measurements. Measuring speaker frequency response with signal generator and SPL meter!? Please...
Please read Floyd Toole book and several others, you will thank me wholeheartedly much more, later.

hello, i really hope you could take a look and try to understand on what/why/how our experts doing and try to think or understand, what is sound distortion and the measurement, what an audio analyzer does, what is objective sound quality etc...the Quora link will give you some ideas.

as you guys often quote Toole, i have make my comment in post 107. i also commented Geddes test in post 113.

regarding your comment on tools, i mean i use any combination of these tools to help me build mostly dacs and amps, and also speakers, not just speakers. i have my own home brew way to measure FR.

there is no way to use an LCR meter to measure SPL right?

 

[Sonce]

Quora link? To get some ideas? Please...

Here are ALL links from the top answer in that Quora link:
- Wikipedia link about Total harmonic Distortion (zero connection to the flat frequency response topic!)
- link to The Audio Measurement Handbook by Audio Precision (did you actually read that handbook?)
- Wikipedia and GSU links to Equal Loudness Curves (very basic stuff)
- Salford University link to Sound quality metrics: "sharpness", "boom", "roughness", "tonality", etc. ... for "engine and car noise", and believe it or not, for "Domestic appliances such as electric razors" !!! (again, zero connection to the flat frequency response topic!)
- Wikipedia link to Mean Opinion Score (arithmetic mean over individual ratings from 1 to 5. Again, zero connection to the flat frequency response topic!)
- Wikipedia link to PESQ and POLOQA (tests of speech quality in phone and IP networks. Again, zero connection to the flat frequency response topic!)
- Wikipedia link to PEAQ (patented algorithm for objectively measuring perceived audio quality. Something, at last!)

It is very illuminating to quote the occupation (and some answers) of the individuals who gave answers in that Quora link:
- audiologist
- "work with audio for a living" ("Now listen to the A 10 loudspeakers from Yamaha one of the most flat speakers you will ever encounter" Yamaha A10 is PA loudspeaker - not flat at all. And if he means Yamaha NS 10 studio monitor, well... flat response... )
- sound engineer ("there are two main measurements you can make to assess if a piece of audio equipment is of high or low quality. These are: 1) flatness of frequency response"
Ironically, you are negating this Quora answer!?)
- amateur guitar player
- "I make music"
- "Car Audio World Champion" ("If it sounds good to you, that's what matters.")
- AV professional ("The only specs that I find of fundamental value are the size, weight and power draw." )

So, we indeed got some ideas about Quora...
In post #107 You didn't comment anything about Toole's book.
Please explain your "home brew way to measure FR" of loudspeakers and post some of your loudspeaker measurements.

 

[celef]

For loudspeakers I do not think there is a such thing as accuray or quality, not in a universal way. All loudspeakers i ever had heard is dependent on the room it plays in, and ever since modern home recording became available tonal balance has gone out the window, but resolution has skyrocketed with a apparent good sound quality.
Building a trully full range loudspeaker today is begging for trouble, you must like a soundengineer adjust freq response for near every track you listen to, and that is not musical enjoyment in my book

 

[jazbo8]

@kinsei - it’s against the Forum Rules to “Improper use of the Quote function such as altering the words or meaning of the quote, misquoting or lack of quote attribution.” Your post has been deleted.

Thread closed for maintenance.