Great line and well said!

'Complicated' people do too.

:)

@@jamesdoranto9013 steve guttenberg is simple guy that needs a haircut and shower and change of those loud t-shirts.

​@@jamesdoranto9013 Simple and simpleton is completely different. Do not confuse them.

Thanks for chiming in Greg. I suspect this is true of just about any crossover designer.

I always design crossovers with one speaker. When things are done correctly with one speaker, two speakers in stereo will always sound amazing!

Thanks Poul. You are very kind. I wish this kind of information was more widely available but it isn't. Hopefully we can remedy it with this format.

@@AudioScienceReview keep it up! It is a relief that someone is not just talking about their feelings... still appreciate your short subjective reflections.

​​@@jungtarcph Speakers/reflections. I see what you did there. 😆

Ah, wonderful to hear about such first hand experiences!

That right there, is a funny line! :)

toooo funny!!! ( :

Thanks Joe. See you then!

Wonderful. Thanks for watching and commenting Dustin.

That's the hope. Will be interesting if they adopt what research says, or do a video saying this is all wrong because they think so!

Super. Great to see others chiming in who have been doing the same. Folks make it sound like I am a unicorn and only one testing in mono. :)

Wonderful.

Ah, that is very kind of you Antonio. Thanks for watching and commenting.

My pleasure. Thank you for kind remark. Provides the fuel for future videos. :)

Ah, you are very kind. :)

Thanks for watching and kind remarks Peter. Much appreciated.

Ah, didn't realize that. Good to know!

Thanks John. :)

Indeed. People readily accept mono measurement but there is so much resistance to the same for listening tests. Our intuition definitely gets in the way.

Speakers are intended to be listened in stereo so unless you're actually developing one, mono listening brings zero benefit to you as you're never going to listen to them in mono anyway. For a speaker designer, mono listening is necessary naturally. But for a speaker shopper, mono listening does not bring any benefit in my opinion. It's the stereo imaging and the whole setup that matters in the end.

I tried that last time but found an issue. I forget what it was. One of them I can fix (it fades out the mouse) but there was another reason I forget. But yes, sorry about putting you all through looking at the full output of PowerPoint. I hate it when others do it but here I am doing it. :)

@@AudioScienceReview Ahh no worries, I can deal with looking at the powerpoint ui in exchange for top tier information :)

@@AudioScienceReview Save the powerpoint as a PDF and open it using a PDF viewer maybe? As a Linux user I have lots of experience avoiding and working around ppt files!

@@theterriblepuddle1830 I see your point, but they weaned me off the drugs as part of the recovery process. Shame really, because I quite liked the drugs.

I still have back issues of the original Sound & Vision magazine (Canada), where they were using the NRC facilities and double blind testing and scoring for the speakers they were reviewing. The highest rating I ever saw them give to a stereo pair was the Energy Veritas 2.8 (a score of 7.9), but they had several 5.1 setups that scored higher, the highest being a Sound Dynamics THC-22 based system that was scored an 8.8. [Edit] Here's the list if you want it: S&V Issue/ NRC Fidelity/ Brand/ MSRP/ Model(s) Home Theatre 02/1997 8.8 Sound Dynamics $1,585 THC-22 main/centre; THR-BP1 surround; THS-1000 sub 09/1996 7.5 PSB $2,600 1000main, Stratus C5 centre, Ambient II surround, Subsonic II sub 08/1996 8.1 Celestion $1,999 Home Theatre in a Box 05/1996 7.1 Cerwin-Vega $2,150 HT-MDC main/centre; HT-S5 surround; HT12-PWR sub 04/1996 8.5 Polk $4,350 RT16 main, CS350-LS centre; LS f/x surround; PSW200 sub 09/1995 8.5 Axiom $700 AX1.2 main/surround; AX1.2 centre, AX120 sub 09/1995 7.2 Monitor Audio $3,197 300 Home Theatre system: 202 main, C300 centre, 302 surround; no sub 02/1995 N/A Bose $2,799 Lifestyle 12 Home Theatre 03/1994 7.1 Cerwin-Vega $1,770 HT-S6 main; HT-CTR centre; HT-S5 surround; HT-12D sub 10/1993 7.3 Paradigm $890 Titan main, CC-200 centre, Atom surround, SB-100 sub 04/1993 7.3 Energy $1,400 Home Theatre system: ESAT-2 main/surround; ECC-1 centre, ESUB-2 sub Stereo Pair 02/1997 7.4 Acoustic Profiles $999 PSL-8835 04/1996 7.6 Acoustic Profiles $799 PSL-8825 11/1995 7.8 Energy $600 Energy C-2 Connoisseur 11/1995 7.7 Paradigm $360 Mini-Mk3 11/1995 7.8 PSB $1,500 Stratus Silver 09/1995 7.2 Paradigm $450 ADP-150 dipole surround 10/1994 7.5 B&W $4,600 Matrix 802 Series 3 10/1994 7.9 Energy $7,000 Veritas v.2.8 09/1993 7.2 Harman Kardon $3,198 Harman Kardon Sixty 09/1993 7.2 Mirage $500 M-290 07/1993 7.3 Acoustic Profiles $699 PSL 66.2 07/1993 7.3 Paradigm $320 Phantom 04/1993 6.6 KEF $550 K140 04/1993 6.5 Wharfedale $439 Diamond V 02/1992 6.5 Acoustic Research $799 M4 02/1992 7.2 Audiosphere Profile $349 PSL 6.1 02/1992 7.4 Castle $3,660 Winchester 02/1992 7.1 Ethera $2,700 Vitae 02/1992 7.3 Mirage $750 M-490 For comparison, I've owned the Paradigm Phantom and Titan on this list, and both would lose to my current Kanto Yumi's + sub and my former Nuance 330's. The Phantoms were comparatively boxy sounding, and the Titans fatiguingly sibilant.

@@status101-danielho6 Yes, modern speakers sound better than vintage ones. Glad to see that technical progress actually results in better sound for lower cost.

@@johnwright8814 Yes, I think good sound has very much been democratized...as long as you buy a powered or active loudspeaker that's been designed around DSP. I'm not sure if passive loudspeakers really are that much better than even 20 years ago.

@@status101-danielho6 One thing I realised is that directivity control is more important than DSP. I look for the waveguide, which is cheaper than room treatment..

I have not done any mono testing for lossy compression artifacts. So don't know. For a speaker to be perceived as point source, it needs to have a very narrow dispersion. Genelecs are not that.

@@AudioScienceReview Genelec refers to them as The Ones, Ultimate Point Source... They also use nearfield differently. EX: the NFS means near enough to separate the dispersion patters of different drivers, while colloquially nearfield means speakers around arm's length where the direct sound dominates. Or with point source used here it means narrow dispersion, beamy, typically negative for what people want. But with coaxial speakers, it's advertised as a good thing, since their single acoustic center point makes their off axis dispersion better vertically than comparable two or three ways. Love the videos, just wanted to clarify as some may not understand how these words are being used.

Ah, good to know!

Thanks. I can go to sleep now knowing the comments are going to go the right direction. :)

I always test in Mono - its just more clear whats going on.

1 - A discrete mono signal from 3 discrete speakers is the most accurate way to listen to stereo music (left + Mono center + right) A single discrete source for each (correctly made) speaker eliminates crosstalk and gives you tight/impactful midbass without a need for EQ ( you cannot accurately restore bass at a nullpoint with an EQ - but you CAN blow your speakers) 2 - speaker quality should be paramount whether you have 1 speaker, 2 speakers, or 3 speakers 3 - An EQ only works "correctly" with discrete signals but ideally is not required in any case

@@bullwinklemoose7232 my comment was a joke-like ;-)

Yes! Listening in stereo saves your money because cheaper speakers sound good enough in stereo! :)

Good point. They certainly don't do any stereo testing in the manufacturing line.

Since headphones isolate each channel for each ear, I have not found this necessary. Indeed I have found headphone characterization much easier than speakers. That said, I do plan to test the idea of mono listening with headphones at some point.

Single speaker. Content can be just one channel of the music you play. Definitely NOT a pair of speakers.

@@AudioScienceReview Thanks, I understand a lot better after I got time to sit down and watch again. The point about combining signal to mono and out of phase information was helpful as well.

Ah yes!

There's plenty of DAC and DSP which are able to mix mono rendering for both channels. RME ADI-2 DAC Amir owns is one of them.

When I first started speaker testing, I created mono files in my Adobe Audition. But then quickly realized that was not necessary. Much of modern music in the last few decades has similar spectrum in both channels so you can just pick one and run with it. I happen to have monoblocks for my stereo system so just leave one amplifier off.

Generally, As loudspeakers are minimum phase devices, when using “conventional” EQ which is also comprised of minimum phase filters, when you create the inverse of a magnitude response (level/frequency) anomaly you also, by virtue of the default nature of minimum phase behavior, create the inverse of the time domain anomaly (phase/frequency) that accompanied it. This can be observed often and with great repeatability in rooms, cars, and large outdoor or indoor venues where loudspeakers are used. It is often assumed that “because EQs also shift the phase, this must be a bad thing and negatively impact the time domain behavior of the system being EQ’d”. The reality is, When you EQ or “linearize” or “flatten” the frequency response you have also “flattened” the phase response. In other words, you have improved the time domain behavior, not made it worse. This reality is independent of the fact that a multi-way speaker system has a summed, full bandwidth response that is not in itself a minimum phase response. It is also independent of the fact that room reflections which have acoustically summed with the direct sound from the loudspeaker also can yield non-minimum phase responses. This does not change the fact that using EQ has an equally “flattening” or “corrective” effect on the time domain as it does on the frequency domain.

Yes

That is how I test near-field monitors. I have one on the left, and another on the right. Then using my workstation software I can play one or the other channel (with content I have converted to mono).

No. The purpose is to evaluate speakers individually.

All of this is included in the papers that I referenced. AES rules don't allow me to quote too much of the papers.

I think people underestimate how satisfying mono listening can be with a great speaker. Often when I am doing testing a great speaker, I continue to listen to them in mono for a long time with much enjoyment to be had.

I am pretty sure they did not say.

As I showed in the research, stereo responses do not invalidate mono testing. They are simply harder for listeners to do.

Thanks for the kind words. Yes, that is on my TODO list. For now, there are a couple of text tutorials I have written on REW: www.audiosciencereview.com/forum/index.php?threads/room-measurement-tutorial-for-dummies-part-1.4/ www.audiosciencereview.com/forum/index.php?threads/room-measurement-tutorial-for-dummies-part-2.5/

@@AudioScienceReview Thanks so much Amir. Yeah I am way beyond those tutorials. Lol. I would say I am a bit above a beginner. I need to know what I am looking at more in detail etc. I am trying to use RTA in REW to better integrate my sub and I don’t know well enough how to read what I am seeing. Pardon for all that. So as the previous responder mentioned. You don’t believe in room absorption beyond the first reflections? Up to what milliseconds are early reflections? And is the reverb after 20ms? Thanks again !

@@Nightjar726 Understood. :) That is the video I plan to do. The challenge is setting it up and capturing the process using video.

@@AudioScienceReview is there any chance you would do private lessons for a fee ?

@Will who is JohnPM? Thank you

I do not but as I commented to another poster, I routinely continue enjoying sound from a single speaker that performs well, after I am doing reviewing it. It is remarkable what enjoyment you can have with great music and one well-engineered speaker. Mind you, I suspect stereo would be even nicer but it doesn't exclude a great experience from single speaker listening.

@@AudioScienceReview Would this be even more truthful regarding listening to just one omni speaker? Thank you for your reply in advance, Amirm.

Improvements do apply to stereo listening. It simply is the case that as humans, we are worse at comparing speakers in stereo versus mono.

I have done it both ways. As long as you always use one channel, and the content is not heavily panned to one or the other, you don't need to convert to mono. I convert to mono when i have one speaker on the left, and another on the right (e.g. near-field monitors) and want to instantly switch between them. Otherwise when just listening to one speaker, it really doesn't matter. Stereo is of course more convenient because I can just play what is in my library. I just leave the other channel off in my system.

If that is the case, and your pair varies, how is me testing that helps you? My pair could be different than yours, yes? FYI better companies perform matching to 0.5 dB in manufacturing.

@@AudioScienceReview I am not commenting on my own equipment but 0.5 db matching over all para mantas should be fine but do some measurement and listening tests with or without grilles when you have time

@Douglas Blake Like I said, you're designing a crossover, a new speaker, you need a methodology to test it, and it looks like the mono listening works in these situations. But in our listening rooms, that's about the only place where -stereo- performance matters.

@@adlervictor So you continue to believe that stereo listening is 'better' in spite of the evidence exhibited in the studies? Weird, if you were to talk about any other topic, people would think you're insane or unreasonable. But for some reason it's totally fine to have such opinions in Hi-Fi.

​@@abdo-dr1tu I'm not disregarding the value of these tests. I love what Amir is doing, bringing light to the subjectivism that dominates the HiFi world. In my opinion, and I think in a free world, I can have one; this methodology can only tell part of the picture. I totally understand the limitations and the complexity of testing a pair of speakers in stereo, but in the end, it is what the vast majority of us have in our listening rooms. What we have here it the evidence to corroborate the topic. But I'm not alone with this opinion; you can see some other comments or other literature covering the speakers' different performance when evaluated as mono or a stereo pair. The book - Sound Reproduction: Loudspeakers and Rooms - by Floyd Toole - is a good example. Or maybe I'm not just a simple guy.

As I explained in the video, results of mono testing translate to stereo testing. No speaker changes ranks from mono to stereo in controlled tests as presented. Also, there is such thing as center speakers and sounds that only play out of one speaker. For me to test in stereo, it would also heaving drag in my room's design. Surely that is not applicable to your setup. Most important thing is this: you want the most reliable information you can get from a reviewer. To the extent stereo listening heavily reduces the chances of a reviewer hearing the flaws in speaker design, that is NOT the type of data you should seek.

​@@AudioScienceReview Thank you for coming here to explain your point of view. Much appreciated. I'm not expecting to see from your reviews the results of a stereo setup in your living room, although even for mono testing, this effect cannot be ignored. My opinion, corroborated by the tests described in the book I've mentioned, is that a poorly rated speaker in a mono test can archive better results when evaluated in a stereo configuration (page 131). Undoubtedly, if the speaker performs well in a mono test, its performance will be equal or better when in a stereo configuration. Anyway, I don't want to make this a big discussion; it's just my opinion that the final verdict is to listen to the setup in our own listening rooms.

If I understand your question, no, when testing mono, only one speaker is playing.

No. Differences in speakers in stereo is still there, just harder to hear. With experience, you may become better at hearing artifacts of the speaker even when listening in stereo. Also, content can easily be mixed to come out of one speaker more than the other. And in home theater, center speaker is always "mono." Have you seen how people drink water between samples in formal food taste tests? You don't want to say they should not do that because you don't drink water that way. Same here.

If they are audible in stereo they are identifiable in stereo. If they are inaudible in stereo then they don’t matter

Very true. Sometimes for in-room EQ people measure bass with both speakers playing but that domain is a function of the room more than the speaker.

Indeed simpel, disconnect one channel of the input.

It has to work, assuming you are asking to test them in mono mode.

electrical and mechanical differences between left and right drivers in headphones are most prominent in dynamic drivers A mono sine sweep starting at 20hz will never reach the highest frequency you can hear (if you have normal hearing) before it begins to produce a combing effect and the mono signal begins panning left to right to left to right The panning effect increases with frequency and is found in ALL headphones / meaning that you will NEVER have absolutely perfect stereo imaging at all frequencies The panning effect is far less noticeable on high quality planar magnetic headphones and start at a higher frequency than dynamic drivers Along with frequency response, transient response and distortion levels, the imaging capability of perfectly matched drivers in headphones makes a BIG difference but will never match the positional imaging realism or accuracy of correctly manufactured speakers using discrete signals in 3 speakers from properly decoded stereo information A PAIR of speakers will never sound as good as a high quality and properly decoded 3 channel speaker system Likewise, a pair of headphones can never reproduce the REALISM or imaging accuracy of a high quality and properly decoded 3 channel speaker system

Ah, you noticed! I forced my poor wife to give another covid haircut. It has been that way for over a year now.

@@AudioScienceReview covid-haircuts are cheap even if they look botched a pair of clippers has saved me hundreds £££ no need to go to a hairdressers again.

You clearly never heard Lyngdorf RoomPerfect (I think). Nothing comes even close in my opinion. Or do you mean REW?

@@afrancois1968 audyssey, I get what it does for bass but that's it. Anything above the transition frequency is pointless. But my bass response was already flat without EQ

Only if your content is heavily panned into one channel or the other. With modern music, I find both channels have enough of the music in them to not matter in my testing.