I'd run tests on the signal chain el' Ol. It could be a component in the chain that is throwing in a distortion on one channel and not the other.
I tried oversimplifying this the other day. I was wondering with an arbitrary room and with an arbitrary set of speakers what would the 1st, 2nd, and 3rd reflection be on one slice of the horizontal axis, what would the FR be of those reflections, and where would they originate from. This is the room I came up with - there is really no reason for the size except that I wanted it large enough to also setup surround sound. And I wanted to see if say I new the response of a speaker I was planning on using could I make a room that utilizes the off axis response of that speaker to achieve an ideal 1st reflection. Even simplifying it this much it still seems complicated to me. Like how should I treat reflections in terms of direction? Are reflections omni directional? Anyway theory smeary here is the room I came up with. Anyone have ideas about what dimensions I should be using and a speaker with measurements to use?
I tried oversimplifying this the other day. I was wondering with an arbitrary room and with an arbitrary set of speakers what would the 1st, 2nd, and 3rd reflection be on one slice of the horizontal axis, what would the FR be of those reflections, and where would they originate from. This is the room I came up with - there is really no reason for the size except that I wanted it large enough to also setup surround sound. And I wanted to see if say I new the response of a speaker I was planning on using could I make a room that utilizes the off axis response of that speaker to achieve an ideal 1st reflection. Even simplifying it this much it still seems complicated to me. Like how should I treat reflections in terms of direction? Are reflections omni directional? Anyway theory smeary here is the room I came up with. Anyone have ideas about what dimensions I should be using and a speaker with measurements to use?
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What a giant shame. A screwed connection in one crossover was not connected, so the bass section was not working. The strange thing is that exchanging the crossovers had no short-term effect. Also strange that I heard everything on the left on my other system. The result of fixing the problem in contrast was an immediate one.
Shall anybody tell me that frequencies below 200 Hz are not relevant for source localization.
Shall anybody tell me that frequencies below 200 Hz are not relevant for source localization.
Reflections can either be perfectly directional (specular) or omni-directional (non-specular) or just about anything in between, and this can all change with frequency. The subject of reflections from real materials is vast and there are no simple answers. The closer to perfectly smooth and rigid the surface the more specular it becomes - completely analogous with light from a shiney surface.
yes indeed
what is important - with CFS (quasi-omni mono setup I have proposed here after Carlsson) there IS imaging and the sense of space IS NOT reduced, actually it is quite the contrary in comparison to standard stereo
one has that "better impression that instruments are "really there" than a conventional setup" in the words of el`Ol, this "reach out and touch" effect that is "hard to describe to someone who hasn´t heard it"
spatial presentation with CFS certainly differs from the stereophonic one in lack of laterality ("left-right" extension) of the auditory scene
instead CFS projects images of sound sources into a kind of a "sphere expanding above the loudspeaker"
yes, with mono (especially CFS) there is no "sweet spot", rather big "sweet area"
and "ease of set up" means that one no longer needs dedicated listening room, You can convert every room big enough into a listening room
it is such a relief after stereophonic room "arrangements" usually meaning destruction of decor and comfort
I had the right-collapse again and it turned out that not the loose screw but a broken wire was the problem. What's good about it: This time I can say what bass driver was not working: It was the right one. Everyone would say intuitively that this can only cause a shift to the left, but obviously an error in the bass on any side enhances my right-tendency and causes the image to collapse to the right.
I still have the slight right-shift caused by my brain, but with both final enclosure AND correct crossover I was just enjoying the Johannespassion with the Bach Collegium Japan from the BIS label more than ever before.
I still have the slight right-shift caused by my brain, but with both final enclosure AND correct crossover I was just enjoying the Johannespassion with the Bach Collegium Japan from the BIS label more than ever before.
Thats what I figured. Like the listeners head for example. Do you think the direct sounds hitting the head are being reflected off of the head in more of an omni directional fashion? I think I am going to just do all the reflections omni to make it easy and I would assume that is the worst case scenario.
Yeah yeah I don't place much importance in room interaction as a whole so this thing to me is just an exercise. But the fact remains and can't be just skipped over that the first reflections in ANY room are going to be from the opposing speaker and the head of the individual and a combination of those bouncing back and forth. So are you really so sure that it's not important if it is actually the first and second late reflection that hits your ears?
I think the reflection off of the opposing speaker will beat the ceiling reflection in most cases. Anyway I was concentrating on horizontal. For this example I am assuming a 2 dimensional room. I know how ridiculous this model is but still I am looking at a pattern I see with loudspeakers and the offaxis response target and seeing if the reflections might have something to do with why speakers use this pattern.
I personally don't think it's the reflections so much at a certain point but more the way off axis response effects phantom imagery or imaging in general.
I personally don't think it's the reflections so much at a certain point but more the way off axis response effects phantom imagery or imaging in general.
Seems you first need to educate yourself on the basic physical principles of diffraction and reflection. Then look at some real world data.
Here's some data (reported) by Olive for reflection detection thresholds:
Here's some data (reported) by Olive for reflection detection thresholds:
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CD or at least CONTROLLED directivity....?
surely, the nearest we can hope to get to a perfect soundstage would be CD or, as above, at least controlled directivity; coupled to a near as perfectly 'sound dead' listening room as possible???
Gedlee, i understand the drive towards CD repro.
Since in nature sounds below a couple of k's arent all that directive; an ON AXIS, CD(if possible/due to limitations) audio system operatind from 2k upwards, and delivered in an acoustically absorbent listening space is the key.
ANY reflections, VER, or spatially, subjectively unoffensive reflection is unfaithful to the recording, and is hence colouration. Its just a more favourable colouration, to the ear at least; in the same way 1% 2nd harmonic THD is nicer to the ear than 1% 3rd harmonic THD.
It doesnt change the fact that is is distortion, which is why ill still with SS amps, and (unfortunately) stick with my 'normal' speakers, and await the day when i have room to house something bigger and more CD.
surely, the nearest we can hope to get to a perfect soundstage would be CD or, as above, at least controlled directivity; coupled to a near as perfectly 'sound dead' listening room as possible???
Gedlee, i understand the drive towards CD repro.
Since in nature sounds below a couple of k's arent all that directive; an ON AXIS, CD(if possible/due to limitations) audio system operatind from 2k upwards, and delivered in an acoustically absorbent listening space is the key.
ANY reflections, VER, or spatially, subjectively unoffensive reflection is unfaithful to the recording, and is hence colouration. Its just a more favourable colouration, to the ear at least; in the same way 1% 2nd harmonic THD is nicer to the ear than 1% 3rd harmonic THD.
It doesnt change the fact that is is distortion, which is why ill still with SS amps, and (unfortunately) stick with my 'normal' speakers, and await the day when i have room to house something bigger and more CD.
I don't think this is true. My experience with loudspeakers is that in contrast to other situations where I am not in the path of the direct sound, with a stereo system I tend to ignore most all of the reflections that are present in a room.
A simple example is to take a set of competent bookshelf speakers that are tightly calibrated and matched and play something mono. For me the more the speakers match and the more controlled the off axis response is the more the sound just seems extremely dry and coming from the center. Unnaturally dry. Even if the recording has reflections embedded on the recording they seem to be unnaturally dry because they are coming at you only from one isolated angle.
It seems obvious to me that if the speakers are good enough (whatever that is) that you will just ignore late reflections unless they are an embedded part of the direct sound firing at you from some angle. I couldn't tell you why but it seems very obvious to me from mixing and controlling reverb on recordings that I can hear the recorded reflections clear as day but the reflections in the room seem totally absent.
such is also my experience
the subject is VERY controversial and our adversaries would keep persuading us to death that we have impaired sense of hearing and/or have no grip of what hi-fi is all about
fortunately for us (or perhaps rather unfortunately?) there are some informed people (of course wheter they are truly informed and/or morally integral is subject to an ongoing controversy) who are not only sharing our experience but who are also trying to give explanations:
see:
Moulton's Takes
see:
http://home.provide.net/~djcarlst/SLCBI.htm
see:
http://www.linkwitzlab.com/Acoustics and Psychoacoustics of Loudspeakers in Small Rooms.doc
I don't think that the room should be acousticaly dead, not at all. In fact all my designs are the exact opposite - very live. (Except at LFs of course).