Exploring Purifi Woofer Speaker Builds

We don't have to get too deep. But lets acknowledge distortion as anything that isnt represented in the source signal. Thats all I ask.....I understand that a certain amount of distortion is 2nd nature to the human. Higher directivity is an advantage towards scientific sound quality in a room, particularly a small room. That is an unrefuted fact amongst professionals. This has no baring on where one should land
MANY studios use monitors closer to typical hifi than the 15" two-ways you post.
The ones with lesser funds or bad perspective maybe?... lets focus on the places where cost is no limit. Thats what I did. Whats a big name Cinema mastering studio look like.
By everybody you must mean you
There was some sarcasm in that statement lol. No harm meant.
Also, your statement about reflections mucking up the sound directly conflicts with listener studies that actually have been done, where some reflection is preferred.
This is where you choose to walk a line.... Listener preference or truth. There are people who would rather her the signal, unadulterated. That would be something closer scientific sound quality. What you prefer to hear, has no effect on the signal....
What you said is like saying " They did a study and discovered people prefer to wear glasses tinted slightly blue"
What I am saying is that, scientific sound quality, at its best, represents glasses with a completely transparent lens.... And this is Universally accepted for scientific sound quality. Recreation (attempts at) of the perfect IR being the most popular metric that I know of.
Neither of us is wrong. But I am right.
 
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Higher directivity is an advantage towards scientific sound quality in a room, particularly a small room. That is an unrefuted fact amongst professionals.
Sound quality is a very difficult thing to measure, adding the word scientific doesn't make it any easier. The definition of that term is not universal so you will get very different responses from people when you use it. Using a speaker with narrower directivity does reduce the room contribution, and does in general make the signal that reaches your ears more closely resemble what came out of the speaker. The problem is that not everyone likes that presentation, it is not a universal preference.

If you watch some of the room treatment videos from Audioholics featuring Anthony Grimani he has a slide that says reflections ~= distortion, and explains it that most of the time reflections will distort the sound and make it sound worse and not as realistic, but also that not always and not in every situation and that sometimes there have been cases where leaving reflections in have worked better.

I know you like to be bold and reductive but audio and acoustics strongly resist that idea.
 
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Sound quality is a very difficult thing to measure, adding the word scientific doesn't make it any easier. The definition of that term is not universal so you will get very different responses from people when you use it. .....I know you like to be bold and reductive but audio and acoustics strongly resist that idea.
Very well said, but scientific sound quality as in the epitome of it, is a 1:1 transfer function, that is, the perfect transient... how could that not be universally understood by the professional community? There are what a hand full of other approaches... but most simply Said, 1:1 transfer function... thats hard to refute.

The very definition of distortion implies that anything outside of a 1:1 transfer function between the signal and the ear, is a distortion.

Definition of distortion​


1: the act of twisting or altering something out of its true, natural, or original state : the act of distortinga distortion of the facts
2: the quality or state of being distorted : a product of distorting: such as

Scientifically, being free of distortion, is the metric of sound quality. Any change of time/amplitude/frequency domain, is distortion, perceived or unpercieved alike.
 
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but scientific sound quality as in the epitome of it, is a 1:1 transfer function, that is, the perfect transient... how could that not be universally understood by the professional community? There are what a hand full of other approaches... but most simply Said, 1:1 transfer function... thats hard to refute.
The simple reason is that some people don't prefer it, There are Euphonic distortions that some people like, why are tube amps still so popular. Haas kickers were removed from some LEDE style studios because they made things sound better than they really were.

Perception and preference can be fuzzy. Sometimes having something be a more perfect representation of the signal sounds boring. Adaption is very real, if you listen to something in a flawed way for a very long time, when presented with a more accurate version you may dislike it because it sounds wrong to you.

Production and reproduction are different environments and what someone may want in one is not what the same person might choose in the other. There is a story in Floyd Toole's book of some Japanese engineers that chose very dead control rooms to produce in but wanted wide directivity and lively rooms to listen in for pleasure.

There is no universal right answer for every person in every room.
 
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Then I must not use the words "quality" it seems, but its a quick fix;

For those who want an accurate recreation of the signal, A higher directivity will help get you there over a wide dispersion, in a room...
The signal received at the ear will be of higher accuracy to the source with higher directivity or higher Direct energy (which is what higher directivity creates anyway).

Using a speaker with narrower directivity does reduce the room contribution, and does in general make the signal that reaches your ears more closely resemble what came out of the speaker. The problem is that not everyone likes that presentation, it is not a universal preference.
The room really messes with what comes out of the speaker....so even if what comes out of the speaker isn't accurate, the room will make it even less accurate.
There's a difference between what one prefers to hear and what the signal says you should hear.

My personal idea of a quality signal is one that is high Accuracy.....Others may prefer more distortion

I should thank you for correcting me, apparently Quality is a subjective in this field....Luckily, Accuracy is Universally accepted....

Definition of accuracy


1: freedom from mistake or error : CORRECTNESSchecked the novel for historical accuracy
2a: conformity to truth or to a standard or model : EXACTNESS

I was under the impression that scientific sound quality simply meant accuracy, my mistake.....This would mean that whatever the mix/mastering engineer created, is their version of Sound Quality....You will need an Accurate System to experience what that is....It is desirable for some to have an accurate system....Others chose Preference, which is essentially choosing higher distortion. Distortion is the opposite of Accuracy. Its also necessary for sound engineers to use Accurate Tools when engineering sound. So that is why something like this
(15" midwoofer covering midrange till about 800-900hz)
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is highly desirable in the mastering studio, where accuracy is of the it most importance.

So now we can say that the 15" creates a more accurate signal. in a room, then a small midrange that remains omni for much more of its passband, in particular in a small untreated room. I can't imagine that @nicoch58 is going to be happy with this reiteration of what I already was saying.

The 4" woofer is less accurate when in a domestic setting, vs a 15" woofer of similar quality.
 
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Quality is a subjective in this field....Luckily, Accuracy is Universally accepted....
I started out thinking simply too, I'll just make the most accurate speakers I can and that will be that, job done, how hard can it be?

20 years later it turns out that it is quite hard and I have become progressively less sure that it is actually what I want :)
 
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I started out thinking simply too, I'll just make the most accurate speakers I can and that will be that, job done, how hard can it be?

20 years later it turns out that it is quite hard and I have become progressively less sure that it is actually what I want :)
I never thought it was easy.... Your desire to detour could be for any reason. Preference for example...I have some too.
 
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@fluid- sweet as!

I've been to commercial studios and some cost-no-object studios. And true cost no object, because the owner has a passive income and his studio is for working with musicians that come to this remote town at the end of the Pearth. No web presence, no desire for extra work. Word of mouth only. By invitation only- you gotta know a guy who knows a guy who wrote your song. Virtually every synth since the dawn of synths, a few dozen guitars, a few different pianos including a Steinway and the gargantuan Fazioli, too many ADC (because studio nuts believe different ADC sound different) etc. Anyway, he enjoys writing and producing for people who are on retreat in this town. He makes Hans Zimmer's studio look average.

And I can 100% guarantee you that the reproduction equipment in a tiny fraction of the budget. If you think audiophiles are tragics, you haven't seen some of the studio gear heads with Gear Acquisition Syndrome. I'm talking mega bucks of instruments and outboard equipment and DAWs and in-the-box software costing 10 times the monitors. And some ideas of music production that isn't far from voodoo. eg. "You gotta feed it into this Euphonix CS200- it is magic!" Why? No idea? But it works...

The musician is about self expression. The working musician is about earning a paycheck to live. A cynic might think that the pop musician is a $ellout, but the truth is that the pop musician just wants to make as many people connect with her music, than less people. Who on earth wants to write music or songs that people run to cringe, vomit or run away from?

But It's also easy to conflate what a music producer wants to do with what the music listener wants to hear. In recent era there's a habit of getting testimonial from a famous producer or engineer, or attaching a famous name to a product. But truth is Quincy Jones could have written hits songs using any number of studio monitors. The pen doesn't make the writer, but the sales department think it's a good idea to sell to the yooth. Buckethead was seen using a Les Paul. That must be it- I want a Les Paul. Truth is Buckethead probably likes all guitars for different reasons. There is no "best guitar"

And the in the studio who's paying for these monitors or are they given on long term loan? Never mind, you're never going to get into the original studio or original speaker or what the original musicians heard. Even when there are multiple musicians and producers and engineers involved they are gentle disagreements. But they all understand they are disagreeing for preference. Truth is that there is no truth.

Two musicians might connect musically and create really interesting stuff. And the third might say well it's great that you're doing is musically ground-breaking that but I've got nothing to offer, so I'm going to leave. This third musician is the one who creates hits records and is only interested in creating hits (=music that more people will enjoy). There's no right or wrong. Variety is the spice of life.

You just got to know your core principles, and you don't have force it on other people.
 
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Studying, researching, building, testing and measuring is what did it. Amazingly, engaging in pointless philosophical debates didn't help much at all ;)
Pointless, is a subjective idea. Accuracy, is more Objective. What you choose to engage in, is your own personal choice. What you engaged in or did not.... is a fact. If I say you engaged in a conversation that you did not....that would be an inaccurate statement. A distortion of the truth.

Larger radiating surfaces, and ones that create more directivity can provide a higher degree of accuracy, to the drivers original produced signal, to your ear, in a room. If we take this type of speaker and tune it to be accurate to the signal it is being sent. The degree of accuracy to the original signal becomes higher as well.
The degree of accuracy to the original signal is less, in a room, with or without acoustic treatment. So by lessening the effects of the room, Signal Accuracy is increased

Thats not an opinion, or philosophy, thats logic and science

Truth is that there is no trush.
plz explain this scientifically in regards to recreating a signal via loudspeaker. To remove distortion is to make a more truthful speaker....Purifi worked so hard to remove distortion...And you are saying it is in vain, seemingly, You could be saying that Purifi also agrees with me, that removing distortion is important, and that anyone who disagrees with that, is not likely interested in what Purifi has to offer. The impulse response test is a measurement of distortion, larger woofers, waveguides/horns, things that cause more direct energy, have a sharper IR in a room, ie less distortion. Distortion being, deviation from original signal..
 
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Pointless, is a subjective idea. Accuracy, is more Objective.
Being able to correlate the subjective to the objective is where the rubber meets the road. When you can work out why something sounds the way it does progress can be made. Sound and perception follow their own rules, they can be prescribed and predicted but they are not always logical to the human mind. Either way I'm done feeding the monster today.
 
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When you can work out why something sounds the way it does progress can be made.
Oh you mean The impulse response? May be not perfect, but its better than nothing? Much smarter people than you and I came up with it lol.

"Impulse responses measured using logarithmic sweeps separate distortion from the linear part of the system response. The distortion components appear at negative times, behind the main impulse. Analysing the frequency content of these components allows plots of distortion harmonics to be generated"
 
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You could be saying that Purifi also agrees with me, that removing distortion is important, and that anyone who disagrees with that, is not likely interested in what Purifi has to offer. The impulse response test is a measurement of distortion, larger woofers, waveguides/horns, things that cause more direct energy, have a sharper IR in a room, ie less distortion. Distortion being, deviation from original signal..

Purifi knows my position regarding their products.

MP3 or OGG or other lossy compressed data is "less truthful" than .WAV or .FLAC
H2.64 or H2.65 is "less truthful" than raw uncompressed video

But what do we gain with lower data rates? Higher resolution or higher frame rates or both or ability to store more and ability to transfer/ stream more in real time. That answer was solved through testing of human perception and preferences.

The search for the transducer with 96dB SINAD continues. Sure that's great. How far do we need to go? Or should be be putting our resources elsewhere (what what else is important?)

History has shown that the search for the 144dB SNR in audio DACs is fun and interesting from an academic point of view.
But for the consumer there's no need. Deploy those clever people to do something else please.

I'm off to feed my dog...
 
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That answer was solved through testing of human perception and preferences.
A slippery slope, in the video I posted with Earl, Erin stated a preference for distortion in some listeners. Still, these are all side notes

"I also share John Meyer's philosophy of trying to be as technically correct as possible, whether doing so appears to be audible or not." - I second that motion. I just wanted to make sure that it was known how to achieve a more technically accurate reproduction, in a room; directivity, or other things that increase direct sound, along with the direct sound being free of distortion as well. Even if a newer method will come along and be deemed superior, to which, I or we will hold as the new standard. Monitoring IR reproduction in the room is not a bad practice, and is, I believe, the most practiced approach to judging system accuracy, in room, at a given listening point. Then theres the test of Square wave reproduction. Who knows whats the newest on the horizon is....
 
I have not looked at this thread in about 3 weeks... what the hell happened? a ****splosion?

So has anyone assessed the subjective midrange sound quality of the PTT6.5X-NAA series to the dedicated midrange PTT6.5 M-NFA series ?

j.

Sealioning is what happened.

Someone in the mood to argue a pet position, decided to 'visit' (to put things charitably) an unrelated thread, and there demand that others debate them. Why do this, instead of make a dedicated thread? Because by derailing an existing thread, you can force others to engage with you, whether they are interested in debating your favored topic or not.
 

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Oh you mean The impulse response? May be not perfect, but its better than nothing? Much smarter people than you and I came up with it lol.

"Impulse responses measured using logarithmic sweeps separate distortion from the linear part of the system response. The distortion components appear at negative times, behind the main impulse. Analysing the frequency content of these components allows plots of distortion harmonics to be generated"
No, an Impulse response is an objective measurement which needs to be correlated in some way to perception if you want to use it as a figure of merit.

As long as you don't make some other important metric worse there is no issue in trying to improve a measurable parameter, just because. That is good engineering. Understanding of what matters and doesn't has changed over time so it is perfectly reasonable to try and do the best you can. But ultimately does it sound any better, more realistic or more enjoyable? If it doesn't it is just different, it is quite possible to have very different looking impulse responses that are difficult if not impossible to tell apart by listening.

It is hard to leave bad information just sitting there without a reply but I will do my best not to engage any further here.