Research Project: Infinity IL10 Speaker Review & Measurements

[QMuse]

I understand the concerns regarding sighted listening and with prior knowledge of measured performance.

These are not the only speakers which produce high levels of HD (2.5dB @ 1.6kHz) at the top of the mid-woofer's passband. Was this level of distortion not objectionable f.e. with the HDI-1600 (2dB @ 1.9kHz) which on top of that produces a much more problematic decay?

This is what @amirm had to say about the JBL:

II put the JBL HDI-1600 on my typical test stand in my listening room with a single parametric EQ to dial out a room mode as I do with all other speakers (verified in this instance to definitely make a positive contribution). The sound from the JBL HDI-1600 in a word is stunning! That extra bass and very good power handling gives full satisfaction. The flat mid-frequencies means all the detail is presented as it should making for a delightful contrast with that bass response.

I put in a little filter to boost where the dip is. It made a tiny difference, providing just a hair more brightness and sparkle. I was OK with or without it.

The sound was so good I sat there listening to track after track. Sans nasty room modes, this is a speaker that is designed to give you the "target room response" without having to use a room EQ to get there.

With 1000 watts on tap and just a single speaker playing, I finally managed to get it to cry uncle and bottom out but that was quite loud. Funny thing, it produced so much bass that combined with its smooth plastic base, it slid back 1 inch on my metal stand!

JBL level of distortion of 2%, which equals to -34dB, is indeed spot on with the one measured for IL10, except that with JBL it looks a bit wider. And still JBL got stellar marks on listening test while IL10 miserably failed. In that context blaming distortion looks pretty much as rushing into conclusion. If testing of IL10 is indeed a research project (as topic title implies) one would expect much more analysis before reaching such conclusion. For example, I made an EQ filter for IL10 to be compared with M16 and suggested repeating the listening test but it was not done as "new speakers are waiting to be tested".

I can understand that one always have to choose between quantity and quality, and it's ok if quantity is a priority, but research cannot be done if focus is not set on quality. When doing research one must accept that numerous tests have to be performed with the same speaker, not only by comparing it with different speakers but also using different EQ filters to listen what is really happening with the perceived response. In that context, either current approach is wrong or "research project" shouldn't be in the thread title.

 

[tw99]

Let me just remind you of the time when our host believed in blind tests. This is what he said in one of his posts from that time:

Personally I attach zero importance to Amir's subjective speaker listening tests due to exactly this. The measurements are where the useful information is.

 

[QMuse]

Some of you may find this graph interesting. It is an overlay of predicted in-room-responses of IL-10 (blue), M16 (green) and JBL HDI-1600 (red).

As you can see they are astonishingly similar in the 100Hz-10kHz range, with JBL having the strongest LF response and M16 the weakest. At HF, north of 10kHz it is the IL-10 which treads calmly there while other 2 speakers are showing some irregularities. While M16 is the best in distortion JBL and IL-10 both have a black spot in the range where it may matter. JLB and M16 were highly praised, IL-10 was heavily criticized. Understanding why it was so is certainly not an easy "research project" and it would take much time. But not be willing to spend that much time on such research project is no excuse for rushing into conclusion that IL-10 didn't sound "right" because of that distortion spike, especially not based on a single non-controlled listening test prior to which detailed measurements were seen.

 

[Absolute]

This is fantastic! Thank you

@amirm ; I've got 50$ waiting to be donated if you can try this out and see if the frequency response alone (be careful of listening height due to shit vertical response) can explain your complaints

And I stand by this. I hope many others do as well. Hopefully this can be a model of "funding per demand" in the future so we can get more funds headed Amir's way.

I really hope you don't take this petition of ours the wrong way, Amir. This has nothing to do with you personally or lack of faith in your abilities, it's just that we desire the right amount of skepticism towards any result, particularly those that are surprising given previous knowledge/assumptions.

 

[BYRTT]

Some of you may find this graph interesting.....

Yes graph is interesting more than 2:1 stretched too wide masking details also there some noice on those curves blue and green in comparison to mine and for example M16 have more low end reach than IL10.....

 

[patate91]

Personally I attach zero importance to Amir's subjective speaker listening tests due to exactly this. The measurements are where the useful information is.

Yep but the thing is Amir publish his subjectiv finding and it has or could have an impact on sales or on what the readers know/believe. The same biaises apply to everyone of us.

Listening and taking listening notes before measuring a speaker doesn't take more time than doing it after measurement. So doing a first blind test is very easy. If what's heard correlate with measurements he can just move on.

On the other hand if it's not the case, publishing the results won't be scientific or at least not rigorous. Sometime doing things more slowy saves time in the long term. Speakers measurement with klippel is a recent projet. There's always room from improvement at the beginning of a project

 

[BYRTT]

Modeled synthetic prediction of EQ the same listening window for IL10 to M16 and vice versa:

 

[QMuse]

Yes graph is interesting more than 2:1 stretched too wide masking details also there some noice on those curves blue and green in comparison to mine and for example M16 have more low end reach than IL10.....
View attachment 71610

My M16 curve definitely looks different from yours in the LF, will check it out.

Btw, I think you put JBL curve too low relative to the other two, maybe even for 1.5dB. If you raise it it will be more similar in LF to M16 while IL-10 LF would be the weakest.

 

[GXAlan]

Modeled synthetic prediction of EQ the same listening window for IL10 to M16 and vice versa:

Although the dispersion is similar in the red areas, look at the green...

 

[Robbo99999]

It is not constructive when it is the same thing over and over again. I mean for heaven's sake, do I look like I need to be told about the "scientific method?"


Why is this all on my shoulders? If all you want is a listening test/playing with filters, anyone can do that. I have even offered this speaker for others to listen to.

As it is, it reads like constant complaining. Bring some data to the conversation. Please don't quote Sean saying what we already know and him saying he doesn't have the time to deal with this. But somehow I need to step up. I am perfectly fine with where I am in this. If it is not fine with you all, do something about it other than wishing more work for me.

Well if it's not your project I certainly don't see who else's it is. You're doing all the listening tests etc, and no one can tell you what to do....ergo it's definitely your project. If you don't want people to provide their opinion on project direction / analysis or any specifics whatsoever (which is what @bobbooo was doing) then make that clear and take full ownership and do whatever you want & just post the results and people can take it as they find it. If you don't provide direction then other people try to do so by providing their ideas/direction. Someone's gotta steer.

(but yeah, it is possible to listen to advice/ideas and not take it without turning it into an issue, it is your project to do as you wish, you have the final say)

 

[richard12511]

That's the thing I don't agree with. Drivers and cabinets produce colouration and frequency response measurements of not illustrate all types of colouration. I am think we need a lot more research focusing on the audibility of the latter, with proper methodology.
The Spinorama is an oversimplification of a complicted matter.

Wouldn't those driver and cabinet colourations show up in the FR(and thus the spinorama), though?

 

[tuga]

Wouldn't those driver and cabinet colourations show up in the FR(and thus the spinorama), though?

A low-level high-Q blip in the frequency response plot can have a long decay:

https://www.stereophile.com/content/monitor-audio-studio-6-loudspeaker-measurements-part-2

 

[QMuse]

A low-level high-Q blip in the frequency response plot can have a long decay:

https://www.stereophile.com/content/monitor-audio-studio-6-loudspeaker-measurements-part-2

Why would you think the decays from that graph, which are all shorter than 3 msec, would matter apart from their impact on FR, when even a well treated room has decay of 150-200msec at pretty much any frequency?

 

[amirm]

Well if it's not your project I certainly don't see who else's it is.

The measurement data is provided for all. And developed and advanced by others. Listening results are mine because none of you can listen to it. I have offered to fix that by loaning out the speaker.

 

[Robbo99999]

The measurement data is provided for all. And developed and advanced by others. Listening results are mine because none of you can listen to it. I have offered to fix that by loaning out the speaker.

Ok, we see how it goes, was just offering my viewpoint on the proceedings and replies.

 

[tuga]

The measurement data is provided for all. And developed and advanced by others. Listening results are mine because none of you can listen to it. I have offered to fix that by loaning out the speaker.

It would be interesting if the IL10 could be compared with the M16, preferably by trained listeners, but that is unfortunately not practical.

 

[amirm]

It would be interesting if the IL10 could be compared with the M16, preferably by trained listeners, but that is unfortunately not practical.

I will lose all faith in Harman R&D if after all these years, they released a worse sounding speaker for a lot more money in the form of M16!

 

[tuga]

Why would you think the decays from that graph, which are all shorter than 3 msec, would matter apart from their impact on FR, when even a well treated room has decay of 150-200msec at pretty much any frequency?

Isn't the direct sound higher in level than the room decay?

All I have is anecdotal experience. In my late teens I spent many afternoons at the MA distributor listening to most MA Studios and their "resonant" cones and comparing them with other speakers. I have listened to a few speakers with "hard" cones low-passed too high, they invariably sounded nasty with violin recordings.

 

[QMuse]

Isn't the direct sound higher in level than the room decay?

Look at that hump at app 800Hz - it decayed for more than 24dB in less than 2 msec. Room decay is in the range of 10-15dB for first 100 msec so it really makes no sense to talk about things from CSD graphs if they don't affect FR.

 

[tuga]

Look at that hump at app 800Hz - it decayed for more than 24dB in less than 2 msec. Room decay is in the range of 10-15dB for first 100 msec so it really makes no sense to talk about things from CSD graphs if they don't affect FR.

Have you tested it?

Most mids and mid-woofer cross a bit higher than 800Hz where the ear is more sensitive.
What's the decay like at 2 or 3kHz in an average room?
Does the decay character change with directivity?