Poll: Speakers closer to which wall(s)?

[Flaesh]

RDAcoustic

BTW RD Acoustic is (was) here https://www.audiosciencereview.com/...-room-part-2-fine-tuning-the-acoustics.23555/

 

[tmuikku]

Thanks Duke. As an engineer, my principle when approaching audio is
1. Everything in audio engineering is compromise, sometimes technical, sometimes financial, sometimes both. So nothing is one size fit all.
2. Before I can form any opinion about technology, I must audition the best or the most technically accomplished implementation of that technology in their most suitable working environment. If not, the opinion is misleading and worthless.
3. If there are scienctific papers about this subject, the approach is not just reading the headline of this research and repeating like a mindless parrot. The testing condition as well as any limitation of the reasearch need to be understood. The most important thing is that opinions, even from trustable experts, which are only the consequence based on result of the test, not the direct statistical result of the test, need to be evaluated with critical thinking rather than treating it like a Bible.

So I spent nearly ten years trying to hear as much as speaker as possible, especially the ones which measurement has been published, to ensure the quality of tech implementation. At that time, I don't have resources to own expensive speakers, my speaker was a pair of modest KH120A. But thanks to my connection, I have chances to audition them in suitable environments. here is my experience:

1. "normal" speakers: I can't count how many of them I have heard, B&W801, Revel Salon2, ATC SCM50, Neumann KH420, KEF Reference 5, Harbeth SHL5, YG Acoustics Carmel, Sonus Faber Stradivari, Thiel CS3.7 are the most notable ones. Out of those, the jack-off-all-trade is a Revel Salon2 and KH420. But the one I like best and want to own is Thiel CS3.7, too bad they are out-of-business after the death of Jim Thiel.
Even though I like some "normal" speakers, but the more I explore them, the less satisfy about them I get. No amount of placing them can result in a soundstage and imaging I like. Put them near side wall and I get a big but very shallow soundstage, plus the very blurring image. Put them far from side wall, ok I get good imaging now but at the same time soundstage is restricted. It is a big problem for well-done box speakers. Other speakers tries to overcome that by letting peak in frequency response, but it is only sound good with a subset of music recordings. And I don't want to be restricted.

2. For omnidirectional speaker, I have heard the quasi-omni speakers like Bose 901 long before but I don't like them due to their messy FR. I also do not impress with MBL 101 speaker at the show case. Then one of my friend bought a 101D and I got a chance to audition properly. The moment "Aha" happens when we pull it out with the distance from walls is 2 meter. Soundstage is immersive, imaging is great as well, absolutely sumblime. The downside is that the estate to accomondate them. 2m out of side wall to each speaker means that one dimension of room need at least 6m. Due to the fact that the listener need to be 2m from wall as well (to avoid LIBR) then the other side of room will be 7m. So a room 6 m x 7 m is needed. My friend's room is 50m2 but it is not something I can afford just for listening space. The good implementation is rare and expensve as well.

3. Dipole speakers: I heard Magnapan and even owned the LXmini, but while they exhibit some special quality in soundstage, their shortcoming in terms of high frequency extension and low frequency volume is too much to bear. But at least they are promising, so I go to build LX521.4, and it clicks. Small baffle lead to more even off-axis FR, bass module with 2x 10" high excursion L26R04Y per channel is decently enough. Side wall 0.5m-1m with toe-in and 1.5m from front wall is enough to get the wide and deep soundstage with good imaging as well. Another good thing is that it requires room only with around 22-25 m2 to work well, with dimension like 4m x 6m, which is suitable for me.
Even then, LX521.4 is a compromise, albeit a good compromise in term of cost. Living with it for a round six month, I began to notice its shortcoming. It has nothing to do with the concept or its execution, but rather on the cost constraint of its. The MU10RB driver has an uneven FR in working range (2k-2.5kHz) lead to a little bit rough in upper midrange around 2kHz. Secondly, both U22REX/P-SL and MU10RB has high breakup at 500Hz and 1.5kHz respectively which create the not so detail sound signature. Thirdly, their dipole pattern brakes up at 2.5 kHz due to magnet blocking in MU10RB and only comebacks at 6kHz, when dipole tweeters take more responsibility, so it is not a ultimate implementation of dipole as I hope. After that time I go all in with dipole by diy with nude-driver configuration (which I learn from CharlieLaub) and high quality driver like SS 26W/4867, Purify PTT6.5M and Mundorf AMT 25D1.1 plus bass module from LX521 and two nearfield ripole subs. And for my room, it is until now the best for strictly stereo sounds.

4. Cardioid speakers: I only heard the D&D 8C. They are great speaker aside from a less than effortless low midrange, which somewhat remind me of LX521, so I suspect it is because of an 8" Seas driver they use. The nicest thing with great implementation cardioid speakers like 8C is that they can be placed near front wall without detrimenting sound quality. So we need only to focus on the side wall, and a distance of 1.5m-2m from side wall is not that hard in most normal room to create the wide soundtage and great imaging. The depth of soundstage can be done by small toe in but not as impressive as dipole and omni speakers. I think that due to lack of rear dispersion, cardioid speaker is more suitable for multichannel setup, especially the center speaker, than dipole and omni speakers without the need of big room. That why I am in the process of building floorstanding cardioid speakers dedicated for multichannel sound systems.

5. Horn Speaker: In my opinion, great horn systems, with horn supported frequency down to 100 Hz and the right recordings which cues from hall is embedded properly in, is the most lifelike sound system I have heard. Problem is that these recordings are very rare, like great 1960s stereo like Mercury, RCA Living Stereo and Chesky. Modern reverb cue is artifical and sound weird to my ear. Due to the horn, it is even more comfortable in terms of placing than cardioid speaker. But the downsize is the huge size for horn supported frequency down to 100 Hz lead me to thing that it is not for me, just like omni speakers. Most smaller horn systems with horn supported frequency down to 500 Hz, while still sound very dynamic, have an abrupt directivity change which don't like.

Hi,
from your description I gather you want to be in close proximity to speakers to hear strong direct field sound, accompanied with nice envelopment. Have you experimented with this aspect? I mean, you did not mention listening distance on any of these descriptions but I could assume you prefer listening quite close to speakers in terms of how our auditory system hears it, nice accurate phantom image with envelopment. This "close enough" listening distance seems to happen due to auditory system and be function of speaker directivity and room acoustics, also positioning and perhaps some particular aspects of a speaker like poorly implemented crossover being right at some critical bandwidth.

My concern is people pay huge amount of attention to technical details like directivity and distance to walls all based on written details, and at the same time do not consider our auditory system much. How would you exactly perceive distance to walls? My hypothesis is that no matter which speakers you have and in which room you could still get the nice direct field sound, clarity and all that, as long as you shrink the listening triangle enough. Quality of envelopment would vary though. I hypothesize this stuff based on Griesinger papers I've read, basically having clarity with phantom (center) image means auditory system has separated direct sound into foreground neural stream, and suppressed room sound to another neural stream on background. Clarity and envelopment. When there is no clarity, there is only one neural stream as auditory system is not able to pick out the direct sound from "noise", there is no envelopment either, just "one spacious and blurry" sound. Search for Griesinger Limit of Localization Distance, or Auditory Proximity, for details.

There is lots of important stuff related to this idea and concept, but the practical problem is, if you happen to like the close sound as I assume here, but do not know about it yourself it subjects you to confusion. Confusion would be due to not knowing whether there is one or two auditory streams happening, which you can test quite easily walking closer or further from speakers and concentrating listening phantom center clarity, it should change quite suddenly. When you are close enough speakers, your brain locks in and does the separation and anywhere from here and closer to speakers you'd hear the sound you prefer, or should hear. One/two step further over transition the brain loses it and you simply cannot hear sound you prefer no matter which speakers or room, since if your brain is not able to tune in to do the separation of important sound and background sound you'd never perceive clarity or envelopment by definition. Preferred side of transition to listen would vary per recording and could vary with your mood as listening further out is more relaxing, less intense as brain is not paying attention. Now that you are aware of this stuff you could just utilize to your advantage, change listening distance for "better sound" in the moment, toggle switch your brain, at will. Not knowing any of this would lead to false assumptions about things: you could listen on the wrong side for particular recording and consider it bad recording when in fact the mixing engineer was listening and optimizing the other side of the transition, perhaps not knowing about any of this either.

Listening distance kind of abstracts a lot of the details into single auditory phenomena, which makes quite remarkable difference and is relatively easy to hear. As one moves closer to speakers D/R ratio increases, delays and SPL of all early reflections change including vertical ones, and eventually the transition happens, all encompassed no matter the actual details what constitutes to the change. Conversely, no matter what the details are the sound is still blurry if too far. Logically, the transition is more important than any of the small details encompassed.

Now, my hypothesis is that you could go into any room with any speakers, find the transition distance in few seconds and be able to reason about the sound without confusion as you'd know what you should hear and what you should not, which side sounds better to you and to the recording that's playing and appreciate it all better, change side at will. If there is no audible transition you'd know the acoustics (and speakers) is really good, or that there is some severe problems. More importantly, you'd now know a thing about yourself, about your brain contribution to stereo system and what you like and how important that is to you. Basically understand which side of the transition you like better, so you can tune rest of your system towards what you like by reasoning with logic based on the transition and what it means. You could do A/B listening tests with the transition for example, toggle "room sound" on/off at will.

Well, at least this is what I've reasoned with limited experience and it would be very interesting if you were able and interested in taking notes about this, in various rooms and speakers, and post your observations and thoughts about it. Even if all of my writing was doomed to be false assumptions based on too little experimentation and knowledge about how auditory system actually works, utilizing the transition is still very good way to gain listening skill and now you could get into good position for full attention in a live venue as well, with acoustic performers, auditoriums, talking with family members at home, and so on.

ps. Sorry duke I hope it's not too much of a hijack, I've been posting this stuff on multiple threads as you know, and it seems so fundamental and important to me that I'll probably keep on posting until mainstream, or busted as nonsense Cool cool, everyone have fun listening your stereo!