Kali Audio IN-8 Studio Monitor Review

[TimVG]

From "The Measurement and Calibration of Sound Reproducing Systems" -Toole
Regarding perception:

"As a crude generalization, at low frequencies there is evidence of significant room reflection and adjacent-boundary effects. From about 200 Hz to around 600–1000 Hz the energetic sound events happen within about the first 50 ms—listeners are exposed to direct plus a few early-reflected sounds. Above this, for the top three octaves or more, the direct sound is the dominant factor."

 

[Absolute]

I think all of this is unnecessary complicated. The predicted in-room response tells us if the directivity is good or bad. If it's bad, you can't equalize it to make the directivity better, but you certainly can equalize it to make the direct sound worse.
That only makes the speaker bad at both direct sound and indirect sound.

If you have bad directivity, you can still EQ the direct sound (listening window) to become better, but the directivity will still be bad. That may or may not be a big problem depending on distance to walls, acoustics, what particular issues with the directivity etc.

A perfect spinorama speaker will most likely result in a Harman-curve in a real room, not a smooth -10 dB line from top to bottom.

My 2 cents.

 

[TimVG]

One more answer from Toole regarding some past questions of mine

The almost linear downward tilted steady state room curve is what is measured from highly rated, forward firing, loudspeakers in typically reflective domestic listening rooms. It is not a target curve for "room EQ" of flawed loudspeakers, and it is not the target curve for omnidirectional loudspeakers. It is important to have comprehensive anechoic data in order to anticipate and interpret steady-state room curves.
Flat and smooth on-axis & listening window curves are the first objective in speaker design. At the same time it is necessary to focus on off-axis/early reflection behavior which should also be smooth, but not necessarily flat. For this reason, in addition to the traditional directivity index based on sound power, we also calculate a directivity index based on early reflections. The family of curves easily reveals evidence of resonances, as they will repeat in most or all of the spatial averages.

 

[thewas]

I had posted more such comments from Toole in a separate topic
https://www.audiosciencereview.com/...ut-room-curve-targets-room-eq-and-more.10950/
I also agree to most of them but as said some need more investigation. Also as said when things like directivity and room are ideal the response at listeners position is also very smooth descreasing curve that needs no correction above the transitions frequency, the big remaining question though is what is the optimum procedure/compromise in a real world when they are not perfect.

 

[QMuse]

I think all of this is unnecessary complicated. The predicted in-room response tells us if the directivity is good or bad.

You may find it surprising but predicted in-room response actually tells us what response to expect in our room.

Take a look at this snapshot from official CEA-2034 document:

So yes, from above of app 400Hz predicted in-room response correlates with the actual in-room steady state measurement.

Below 400Hz this cannot be predicted as room modes, which are dependent on room dimensions, will affect the actual response.

 

[TimVG]

It is indeed an accurate predictor of a steady state measurement, and here lies the argument. Namely that Toole himself says:

The simple fact is that a steady-state room curve is not accurately descriptive of sound quality

The direct sound has primary importance - it should be as neutral as possible - the early reflections come after and need to resemble the direct sound without obvious colorations.

The resulting smooth, downard tilted curve is the result - in itself it is not a guarantee. If a loudspeaker has a problem in the direct sound (listening window average) and it is compensated for in the early reflection and/or sound power to achieve a nice in-room curve, the resulting speaker will still not be rated very highly in a DBT.

That is how I see it.

 

[thewas]

The resulting smooth, downard tilted curve is the result - in itself it is not a guarantee. If a loudspeaker has a problem in the direct sound (listening window average) and it is compensated for in the early reflection and/or sound power to achieve a nice in-room curve, the resulting speaker will still not be rated very highly in a DBT.

That is how I see it.

And I fully agree, thats why I also prefer buy and EQ loudspeakers with smooth directivity, although weirdly the current Harman metric didn't really punish such a loudspeaker which tricks with its direct sound to compensate the problems it has in its directivity if you look at our loudspeaker ranking and see that this Harbeth got a higher score than the Neumann or 3-way Revel.

 

[QMuse]

"The simple fact is that a steady-state room curve is not accurately descriptive of sound quality "

Which is a kind of contradiction, as you can't possibly get linear steady-state curve without linear ER and SP curves because of their 88% contribution in it. It is also difficult to imagine a speaker which would have perfectly linear ER and SP but lousy LW.

So how comes that steady-state curve, which above Schroeder practically equals PIR, cannot be used as accurate descriptor of SQ but LW, ER and SP can?

Btw, Harbeth has much less linear LW than Revel C52 yet it scored slightly better. Don't you find that also contradictory as LW is supposed to be mayor performance indicator?

 

[TimVG]

P.S. Harbeth has much less linear LW than Revel C52 yet it scored slightly better. Don't you find that also contradictory?

I found it a surprising result as well, I'll admit as much. In fact I'd rather buy the lesser rated IN-8 depicted here than the Harbeth M30. As both of our filtersets have shown, it can be EQ'd to provide an extremely neutral LW as well as textbook in-room curve. I doubt the same can be said of M30 which has a directivity issue.

 

[thewas]

In fact I'd rather buy the lesser rated IN-8 depicted here than the Harbeth M30. As both of our filtersets have shown, it can be EQ'd to provide an extremely neutral LW as well as textbook in-room curve.

Thats what I actually did buying and EQing both my Kali IN-8 and KEF LS50.

 

[QMuse]

I agree, Kali IN-8 defintiely looks like a better choice than Harbeth. It also seems that Harman's scoring system don't put that much weight on LW, right?

 

[QMuse]

Does anybody know by heart how exactly scoring system takes into account LW, ER and SP?

 

[TimVG]

It's explained in this thread: https://www.audiosciencereview.com/...ds/speaker-equivalent-sinad-discussion.10818/

 

[thewas]

It's explained in this thread: https://www.audiosciencereview.com/...ds/speaker-equivalent-sinad-discussion.10818/

And its interesting to see that directly only the smoothness of the Predicted In-room Response (which of course indirectly consists also of DS/LW) is considered and not only of the direct sound or listening window above the transition region, which is the reason the Harbeth gets such a high rating.

 

[TimVG]

I agree, Kali IN-8 defintiely looks like a better choice than Harbeth. It also seems that Harman's scoring system don't put that much weight on LW, right?

Technically, it doesn't even use the LW to calculate the score. It uses the on-axis data instead, which is contradictory. As I understand though, it is only in the last 10 or so years that the listening window has become the preferred metric for 'direct' sound with Harman. The regression model dates from 2005 and with that in mind, is possibly outdated to the latest findings.

 

[TimVG]

The question then becomes: does Harman's double blind test champion, the Salon2, recieve the highest score according to the model? Anyone able to track the curve using CAD and do this?

 

[mitchco]

My original protest was against what I've seen @mitchco state more than once, namely that there is a definite in-room curve which he himself prefers in his room across al sorts of speaker systems. PS: this is not meant as an insult, or to cause offense, I am merely claiming that as @Jon AA has stated, there cannot be a single universal curve due to the various reasons named.

Tim, there certainly is misunderstanding as to what I have said as there are two distinct topics being discussed and both get convoluted. While this may not be the thread, I will be brief as possible.

Sean Olive conducted a number of studies on listener preferences. As I understand it, he had eq'd a Revel F208 flat in-room response and then had listeners adjust the low and high frequency responses until it sounded neutral, accurate, preferred, whatever you want to call it and the result:

As I understand it, this experiment was repeated a number of times with similar results. Next up is headphones, and the same approach was used and an interesting correlation was found:

Again, if you dig into the research, this was a repeated experiment again with similar results.

And then there was a study on room correction products and the results:

The above is summarised in the History of the Harman Target curve

I am going to leave room eq out of this as I feel it really needs an article to explain what the state of the art DSP is doing and how it can be used to one's advantage. Hopefully most folks by now understand that the room is in control below the rooms transition frequency and that good room eq can do wonders.

As one experiment, I eq'd my very narrow directivity JBL 4722 cinema speakers the same as a pair of wider directivity KEF LS50's "in-room" to a target response. Both speakers used the same subs to take out the low frequency differences: https://audiophilestyle.com/ca/revi...ker-comparison-with-binaural-recordings-r768/

The interesting part is that I made binarual recordings of both speakers and then spliced them together in an AB test sequence so that folks can download and listen and hear the difference with their own ears. While the speakers were eq'd along the same target, there is a difference in tonal response due to the large directivity differences between the two loudspeakers. While not perfectly recorded it is an ear opening experience.

I agree with @thewas_ that this is an area that needs much further investigation with more listener preference experiments. If you listen to the above binaural recordings, they are more the same than different, even with the huge directivity differences. As Martijn Mensink, designed of the Dutch and Dutch 8c's says, "I've had the Kii's and the 8c's side by side in my living room for a while. The Kii's too are remarkably good speakers. With just some subtle EQ the two could be made to sound very similar on most program material - to the extent that I might not be able to distinguish them in a proper blind test. I'm still amazed sometimes by the extent to which differences in sound can be explained by frequency response."

I would include myself with the same thought having compared them first hand with virtually the same frequency response (this by just using the onboard PEQ's - no room eq). I believe this is partially why folks (especially speaker manufacturers) don't want formal studies on room eq to take place Nudge, nudge, wink wink, say no more.

So much for being brief, lol! And wildly off topic from the good Kali's. Happy Friday!

 

[TimVG]

@mitchco

Thank you Mitch for the elaboration. I hope you don't take any offense to my comments, it was not intended as such in any case. In fact, you may be in a unique position to help out. Would it be possible for you when time allows, to make nearfield measurements of one of your JBL loudspeakers in their current configuration to determine the quasi-anechoic listening window response from them? In all likeliness they should be close to neutral.

 

[edechamps]

As soon as you put speaker in a real room what you will hear will be according to the predicted in-room response (PIR)

That's not correct. Not according to @Floyd Toole, anyway. A more correct statement would be:

"As soon as you put speaker in a real room what a single microphone at the listening position will measure will be according to the predicted in-room response (PIR)"

There, Toole would agree with you.

This might seem like a subtle distinction. It absolutely is not, and is the main reason why so many people here vehemently disagree with you on this.

The reason why these two statements are very different is because the predicted in-room response (or an actual in-room response for that matter) does not tell you what part of the response is the direct sound and what is reflected sound. But our auditory system can - Toole spends multiple chapters on this very topic. Therefore the in-room response does not contain enough information to fully characterize what you ear.

This is why Toole is often quoted as saying things like "Two ears and a brain are massively more analytical and adaptable than an omnidirectional microphone and an analyzer" (source - his book also phrases it similarly).

In a hypothetic situation where LW is perfect but ER and SP are bad PIR would also end up bad. Is it a good speaker or not?

Not a good speaker, no. Not necessarily horrible, though.

In another hypothetic situation we have not so good LW but perfect ER and SP so PIR ends up really good. Is this a good speaer or not?

Definitely not. Yes, despite the good PIR. Because, again, the PIR doesn't tell you the whole story.

@MZKM , which one would end up with better Olive's score?

It's interesting that you would bring up the topic of the Olive score, because that actually works against you here. Let me remind you of the coefficients. 38% is directly calculated from PIR (NBD_PIR, SM_PIR). But there is also 31.5% calculated directly from On-Axis (NBD_ON).

Now ask yourself this: if PIR really is the be-all end-all when it comes to perceived performance of a loudspeaker in a room, as you seem to think, then why does the score formula mention NBD_ON at all? Keep in mind Olive's model was developed using a statistical method (PCA) whose whole point is to remove variables that are bad predictors, and only keep the smallest set of variables that make it possible to predict preference with a reasonable degree of accuracy. If On-Axis is just a distraction and PIR is really what matters, then how come the statistical model assigns such a large weight to On-Axis, almost the same weight as PIR?

Btw, if that is not the one with perfect PIR and not so good LW then what is the purpose of PIR???

To be honest, I'm not entirely sure. Its limited usefulness is probably why it's not part of the standard spinorama graph as specified by CTA-2034. I suspect it might be a good indicator of overall tonal trend (i.e. to judge an overall bass/treble tilt), I don't know.

 

[TimVG]

To be honest, I'm not entirely sure. Its limited usefulness is probably why it's not part of the standard spinorama graph as specified by CTA-2034. I suspect it might be a good indicator of overall tonal trend (i.e. to judge an overall bass/treble tilt), I don't know.

Perhaps, and this is merely speculation, if a certain brands makes loudspeakers, but also amplifiers and processors featuring automatic room correction software, it is easier to make sure their designs are naturally inclined to follow a predetermined target as I can imagine all but the most expensive units feature anechoic data of all of their loudspeaker models. This would ensure good sound above the transition frequency coupled with effective EQ below it. Why not simply limit correction to below the transition frequency then? Well in some cases I've noticed auto correction up to a couple of 100Hz having trouble setting a relative level compared to the rest of the curve, leaving us with anemic bass or even lower midrange performance.