How loud before the room's modes begin to take effect?
hardwinte
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#1
21st February 2012
Old 21st February 2012
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How loud before the room's modes begin to take effect?

Hi guys.

I don't think this has been asked before, but since people recommend monitoring at 'low levels' and close to the monitors in order to reduce the effect of reflections and reverb and etc, I wanted to know how around how high the SPL levels would be before reflections would be loud enough to screw around adversely with what I'm hearing?

I realize that this will be different for everyone depending on monitor placement in relation to myself and the room, room size, etc.

I listen within 1 meter of my monitors so the sound reaches me pretty quickly. My SPL meter measures my average listening level at around 55-65db A-weighted.

Does anyone have a kind of general answer? Thoughts?

While y'all form your own opinions, I also happen to own a pair of akg k70x. I don't hear much difference between their sound and my monitors at my position and listening levels, except below 100hz or so which is to be expected. My monitors are the M-audio DSM-3. I'm inexperienced however, but that is my experience in my untreated room.
#2
21st February 2012
Old 21st February 2012
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Well, I'm no expert in room acoustics, but I like to think that this depends of the size of your room. Also it depends what do you have in room (shelves - are they empty or not, couches, closets, bed etc.) and how are these things placed.
#3
21st February 2012
Old 21st February 2012
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Nooo, get a nice sounding room and monitor at a decent level and mix it at a good distance from the monitors. Don't mix close up, at low levels - who said do that? Mix at a level that is right for the space! And get in a position that let you hear the sound stage properly, then you'll get a better idea about level, space, depth etc.
hardwinte
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#4
21st February 2012
Old 21st February 2012
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Originally Posted by DavieB View Post
Nooo, get a nice sounding room and monitor at a decent level and mix it at a good distance from the monitors. Don't mix close up, at low levels - who said do that? Mix at a level that is right for the space!
"Mix at a level that is right for the space?" I have no idea what that means. Could you explain? Thanks.

Quote:
And get in a position that let you hear the sound stage properly, then you'll get a better idea about level, space, depth etc.
I can hear the sound stage fine from where I am. I tested it myself with a sine loop sweeping L-R. It goes 180 all around me.
hardwinte
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#5
21st February 2012
Old 21st February 2012
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Originally Posted by Seidy View Post
Well, I'm no expert in room acoustics, but I like to think that this depends of the size of your room. Also it depends what do you have in room (shelves - are they empty or not, couches, closets, bed etc.) and how are these things placed.
Well that's the whole point of my question...perhaps those reflections won't hit my ears very loud if I'm not monitoring loudly, but I have no idea how loud if that is even the right question....
#6
21st February 2012
Old 21st February 2012
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If you are in a large studio then the monitoring level will have to be louder, the ought to fill the room and sound balanced. And you don't want to be mixing that up close.

If the room is small then use near fields but again get the monitoring level to fill the room and get the sound balanced. Monitoring closer in this case will be ok.

The sound stage is the depth, height, width and space of the production / mix. You need to be positioned so you can hear it properly without proximity problems or fatigue kicking in etc. Make sense?
#7
21st February 2012
Old 21st February 2012
  #7
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You cannot escape a bad room by listening at lower levels any and all acoustic nodes affect all of the sound, no matter how quiet. What happens at lower levels is that your own ears will perceive less bass och treble, that's not the same. Always vary you levels when mixing, don't mix only super loud or quiet, or you may be fooling yourself.

If you need to reference your mix without the room getting involved, use a pair of headphones you trust.
hardwinte
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#8
21st February 2012
Old 21st February 2012
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Originally Posted by DavieB View Post
If you are in a large studio then the monitoring level will have to be louder, the ought to fill the room and sound balanced. And you don't want to be mixing that up close.

If the room is small then use near fields but again get the monitoring level to fill the room and get the sound balanced. Monitoring closer in this case will be ok.

The sound stage is the depth, height, width and space of the production / mix. You need to be positioned so you can hear it properly without proximity problems or fatigue kicking in etc. Make sense?
Thanks for your advice DavieB. I am in a small room, but why do I want to get the level up so that it fills the entire room? Surely only I need to hear the output, not the rest of the room. This does not make any sense to me at all.

Before I thought you were talking about stereo sound stage. Rest assured, my positioning is fine (equilateral triangle shape with monitors and myself) as I have already mentioned, and sound stage is perfect. In fact, I don't care about sound stage. I am trying to get answers for loudness level in correlation with reflection levels.
#9
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by hardwinte View Post
Thanks for your advice DavieB. I am in a small room, but why do I want to get the level up so that it fills the entire room? Surely only I need to hear the output, not the rest of the room. This does not make any sense to me at all.

Before I thought you were talking about stereo sound stage. Rest assured, my positioning is fine (equilateral triangle shape with monitors and myself) as I have already mentioned, and sound stage is perfect. In fact, I don't care about sound stage. I am trying to get answers for loudness level in correlation with reflection levels.
Nobody listens to music sitting next to the speakers, they sit some distance from them and turn up the speakers so the sound is at any enjoyable level. Same for mixing / production. When you are closer to monitors there are proximity effects going on, some instruments are difficult to judge properly because you are more sensitive to their frequency range. Being closer makes you turn them down because they are fatiguing. A huge percentage of sound is made by the room itself, which is why rooms are normally chosen because they sound good. My studio for instance has a large vaulted ceiling which allows the sound to disperse in a very nice way throughout the room. It's not too big and not too small, it's not too dull and not too reflective - balanced. I play music at a level which is right for that room, not too loud but not too quiet, it just fills the room nicely. Most studios monitor at levels that fit the size of the room.

Equilateral triangle is wrong. The monitors ought to be positioned front facing without an angle in. The reason for doing that is it creates a much better representation of width in the mix and pretty much essential if you want to fill the room properly.
#10
21st February 2012
Old 21st February 2012
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well, triangle is right, equilateral isn't ideal though as Dave said.

However plenty of monitoring setups have used equilateral triangles and work very well, but that will give you an exaggerated stereo effect (with headphones of course giving an insanely exaggerated while also somewhat broken stereo effect).

What you ideally want, but can't always get with nf monitoring, is an isosceles triangle (google it). you should be further from the speakers than they are from each other. However again, in most near field setups, you end up with something more akin to equilateral. Don't get stressed about it - it's surprisingly common with NF monitors to have equilateral triangles and there is often very little one can do about it.

My setup is equilateral, it's the closest to ideal I can get in my small space. And it's much better than any other setup other than isosceles.
#11
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by dkelley View Post
well, triangle is right, equilateral isn't ideal though as Dave said.

However plenty of monitoring setups have used equilateral triangles and work very well, but that will give you an exaggerated stereo effect (with headphones of course giving an insanely exaggerated while also somewhat broken stereo effect).

What you ideally want, but can't always get with nf monitoring, is an isosceles triangle (google it). you should be further from the speakers than they are from each other. However again, in most near field setups, you end up with something more akin to equilateral. Don't get stressed about it - it's surprisingly common with NF monitors to have equilateral triangles and there is often very little one can do about it.

My setup is equilateral, it's the closest to ideal I can get in my small space. And it's much better than any other setup other than isosceles.
This is pretty much spot on,
#12
21st February 2012
Old 21st February 2012
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Listening at lower levels does nothing for room modes. Waves build up/cancel out whether theyre big (loud) or small (quiet).
#13
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by DavieB View Post

Equilateral triangle is wrong. The monitors ought to be positioned front facing without an angle in. The reason for doing that is it creates a much better representation of width in the mix and pretty much essential if you want to fill the room properly.
That is absolutely 100% incorrect. Because high frequencies are more directional than lower ones, you need to have the tweeters pointed at your ears. Read the manual of any respected monitor company and you'll find this to be the case.
#14
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by dasnub View Post
That is absolutely 100% incorrect. Because high frequencies are more directional than lower ones, you need to have the tweeters pointed at your ears. Read the manual of any respected monitor company and you'll find this to be the case.
The sound radiates from the front of the speaker. If the angle of the speaker is toed in then the sound from both speakers cross over in a way that distorts your perception of width. The distance between the speakers is important as is the level for the room you are in.
hardwinte
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#15
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by dasnub View Post
Listening at lower levels does nothing for room modes. Waves build up/cancel out whether theyre big (loud) or small (quiet).
Yea this makes sense, I was kinda afraid of that one.

Well it shouldn't be a hassle to counter anyways. Just needed it told to me so now I can't trust my monitors and room
hardwinte
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#16
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by DavieB View Post
Nobody listens to music sitting next to the speakers, they sit some distance from them and turn up the speakers so the sound is at any enjoyable level. Same for mixing / production. When you are closer to monitors there are proximity effects going on, some instruments are difficult to judge properly because you are more sensitive to their frequency range. Being closer makes you turn them down because they are fatiguing. A huge percentage of sound is made by the room itself, which is why rooms are normally chosen because they sound good. My studio for instance has a large vaulted ceiling which allows the sound to disperse in a very nice way throughout the room. It's not too big and not too small, it's not too dull and not too reflective - balanced. I play music at a level which is right for that room, not too loud but not too quiet, it just fills the room nicely. Most studios monitor at levels that fit the size of the room.

Equilateral triangle is wrong. The monitors ought to be positioned front facing without an angle in. The reason for doing that is it creates a much better representation of width in the mix and pretty much essential if you want to fill the room properly.
I don't know where you get your information from, but the majority of people listen to music right next to their speakers....that would be the people on their computers and laptops, as well as the headphone users - pretty much everybody. The only people who aren't are the clubbers, home theatre owners and car speaker enthusiasts. The restaurant people and party people don't listen to the music.

Proximity effects? Then what about headphone mixing? Surely that would produce the same 'bad' results. Yet I've seen many who do that and produce perfectly agreeable results. I will search more about this one thanks.

Find some instruments fatigueing, causing me to turn them down? I know you're not just blabbering, but I haven't found this to be the case at all with any instrument or sound excepting excessive highs, which is natural.
#17
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by dasnub View Post
That is absolutely 100% incorrect. Because high frequencies are more directional than lower ones, you need to have the tweeters pointed at your ears. Read the manual of any respected monitor company and you'll find this to be the case.
sorry, misread the first time.

you're correct. and it's not just high frequencies - it's all related to the width of the moving diaphragm compared to the wavelength of the frequency.

sorry DavieB, can't agree with you about your concept of avoiding toeing the speakers inward.

Also there is no inaccuracy or distortion of any kind generated by toeing in your speakers to your head.... they are more or less a vertical line source (assuming you're not doing anything stupidly incorrect like placing your monitors on their sides like so many dumb ns-10 photos on the internet depict LoL).

As a matter of fact, if you think about the physics involved, toeing them in could technically reduce distortion generated from the outer edge (furthest from the other speaker) of your woofer being further away from your ear than the inner edge (closest to the other speaker).

There is absolutely no scientific reason to avoid toeing your speakers inward unless you're using some kind of oddball speaker design (like polk sda systems with the signal cancelling drivers in opposing sides (google it)).

There's always a slim chance I'm wrong about this of course - it's only my opinion, but it's an opinion based on many years of research into acoustics, audio reproduction, and specifically speaker design theory (and practice).
#18
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by hardwinte View Post
I don't know where you get your information from, but the majority of people listen to music right next to their speakers....that would be the people on their computers and laptops, as well as the headphone users - pretty much everybody. The only people who aren't are the clubbers, home theatre owners and car speaker enthusiasts. The restaurant people and party people don't listen to the music.

Proximity effects? Then what about headphone mixing? Surely that would produce the same 'bad' results. Yet I've seen many who do that and produce perfectly agreeable results. I will search more about this one thanks.

Find some instruments fatigueing, causing me to turn them down? I know you're not just blabbering, but I haven't found this to be the case at all with any instrument or sound excepting excessive highs, which is natural.
I was thinking about what happens in a studio when there are many people listening to the music. They are sometimes at the back of the room spread out so the monitoring level needs to reach them also. You might have the artist and producer with an engineer or someone from the label all wanting to hear it. The point I'm making is that with a low level toed in system, whilst acceptable for one person sat in close, this is no good for other people in the room as the sound stage is too narrow, there is no width. This is my point about the perception of width.

Proximity effects is when the perception of a sound changes when you are close to it and it largely to do with level. Monitoring close and loud is bad, monitoring close and quiet is ok only if you are the only person who is there to hear it. In my experience that is not always the case. Headphones are very useful when working with mics and for general monitoring, checking a mix etc but they don't replace monitors. Proximity effects are most noticeable when using mics, the closer you get the more bass is captured, the further away the more air is captured.

High mid range is fatiguing when too loud, this is where we are most sensitive - the harsh frequencies. The low frequencies are where we are least sensitive which is why this requires more level to be heard. If you are mixing a sound in the sensitive range and are close to it the tendancy is to turn it down.

I'm not being funny with you guys I'm just pointing out the problem with a toed in, close up, low level monitoring set-up.
hardwinte
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#19
21st February 2012
Old 21st February 2012
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Quote:
Originally Posted by DavieB View Post
I was thinking about what happens in a studio when there are many people listening to the music. They are sometimes at the back of the room spread out so the monitoring level needs to reach them also. You might have the artist and producer with an engineer or someone from the label all wanting to hear it. The point I'm making is that with a low level toed in system, whilst acceptable for one person sat in close, this is no good for other people in the room as the sound stage is too narrow, there is no width. This is my point about the perception of width.
Well, not only would that situation be different for every person/studio, it is also bad mixing/monitoring practice as only the people in the sweet spot should be working the mix. As you have said earlier, you are mixing for how people listen to music. Well, no one listens to music standing around in a room. And it isn't possible to completely optimize 'width' and 'soundstage' for multiple positions in the room.

Quote:
Proximity effects is when the perception of a sound changes when you are close to it and it largely to do with level. Monitoring close and loud is bad, monitoring close and quiet is ok only if you are the only person who is there to hear it. In my experience that is not always the case. Headphones are very useful when working with mics and for general monitoring, checking a mix etc but they don't replace monitors. Proximity effects are most noticeable when using mics, the closer you get the more bass is captured, the further away the more air is captured.
Why are you going into tracking technique? Headphones are fine for detail check, I wouldn't use it for imaging.

Quote:
High mid range is fatiguing when too loud, this is where we are most sensitive - the harsh frequencies. The low frequencies are where we are least sensitive which is why this requires more level to be heard. If you are mixing a sound in the sensitive range and are close to it the tendancy is to turn it down.
I think you're a bit mixed up here. Turning down 'harsh' frequencies is desirable, not something to be avoided.

I can tell your advice is good-natured, but it is not making any sense at all, and you're talking about things unrelated to my question.

I was going to ask if anyone had any actual information, but I think I've worked it out myself. Thanks all for helping me think.
#20
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by DavieB View Post
I was thinking about what happens in a studio when there are many people listening to the music. They are sometimes at the back of the room spread out so the monitoring level needs to reach them also. You might have the artist and producer with an engineer or someone from the label all wanting to hear it. The point I'm making is that with a low level toed in system, whilst acceptable for one person sat in close, this is no good for other people in the room as the sound stage is too narrow, there is no width. This is my point about the perception of width.

Proximity effects is when the perception of a sound changes when you are close to it and it largely to do with level. Monitoring close and loud is bad, monitoring close and quiet is ok only if you are the only person who is there to hear it. In my experience that is not always the case. Headphones are very useful when working with mics and for general monitoring, checking a mix etc but they don't replace monitors. Proximity effects are most noticeable when using mics, the closer you get the more bass is captured, the further away the more air is captured.

High mid range is fatiguing when too loud, this is where we are most sensitive - the harsh frequencies. The low frequencies are where we are least sensitive which is why this requires more level to be heard. If you are mixing a sound in the sensitive range and are close to it the tendancy is to turn it down.

I'm not being funny with you guys I'm just pointing out the problem with a toed in, close up, low level monitoring set-up.
Don't mean to be argumentative, but you're giving out bad information here and I'd hate the newbies to read it and do the same thing you're doing. When you move your head off axis of a speaker, you are changing the frequency response you're hearing.

An example from the Focal CMS manual:

"The CMS loudspeakers are near field monitoring loudspeakers and should be positioned at a distance between 1 and 3 meters from the listener, pointing towards the listening position. They can be sitting on the console top, hung or even placed on appropriate stands. In any way, it is recommended that the tweeter is at a height from the floor approximately equivalent to that of the listener’s ears. If required, it can make sense to place the speakers upside down so that the previous rule is better fulfilled.
The CMS loudspeakers could be placed vertically or horizontally depending on the environ-ment."


Interestingly enough, they also say there is no problem laying the speakers on their sides, which is often mentioned as a no-no (like it was by someone above.)
#21
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by DavieB View Post
I was thinking about what happens in a studio when there are many people listening to the music. They are sometimes at the back of the room spread out so the monitoring level needs to reach them also. You might have the artist and producer with an engineer or someone from the label all wanting to hear it.
I'm was thinking that the guy talking about it in this thread was working alone, nobody in the room to play to, and so on.

if you're talking about directing sound elsewhere, this is why we have the "large" monitors set further apart and further back and with wider room separation. If you only have the one set of monitors, maybe you have a point for dispersion etc.

I got the impression that the OP was asking about himself, for himself, working alone with his small system. If my impression was correct then toed in and so on is correct.

imho, ymmv, yadda yadda.
#22
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by dasnub View Post
Don't mean to be argumentative, but you're giving out bad information here and I'd hate the newbies to read it and do the same thing you're doing. When you move your head off axis of a speaker, you are changing the frequency response you're hearing.

An example from the Focal CMS manual:

"The CMS loudspeakers are near field monitoring loudspeakers and should be positioned at a distance between 1 and 3 meters from the listener, pointing towards the listening position. They can be sitting on the console top, hung or even placed on appropriate stands. In any way, it is recommended that the tweeter is at a height from the floor approximately equivalent to that of the listener’s ears. If required, it can make sense to place the speakers upside down so that the previous rule is better fulfilled.
The CMS loudspeakers could be placed vertically or horizontally depending on the environ-ment."


Interestingly enough, they also say there is no problem laying the speakers on their sides, which is often mentioned as a no-no (like it was by someone above.)
yes, interestingly enough is right, because putting them on the side means that as you move from side to side the frequency response will change along with introducing phase issues. where as typically it's desireable to keep them vertical because then the horizontal dispersion will only gradually reduce HF dispersion, not alter the entire frequency response through the crossover range as is the case with horizontally set speakers.

When sitting at your console your head stays, more or less, vertically consistent, but you can wheel around back and forth, side to side. Therefore it is almost always preferable to have your monitors setup vertically to prevent rather drastic tone differences through the crossover range as you move your head only a matter of a foot or so from side to side.

The physics are well understood - focal was rather amis in not explaining that point in their manual. focal monitors like all others will perform better vertically than horizontally unless you only move your head up and down, NEVER moving from side to side, while working at your computer (which is obviously an unlikely scenario for most humans).

sadly I think that pokes a hole in the focal documentation, although they are undeniably one of the greatest driver manufacturers in the world (I have focal tweeters, alone with jbl woofers, in my custom made compact near fields).
#23
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by dkelley View Post
I'm was thinking that the guy talking about it in this thread was working alone, nobody in the room to play to, and so on.

if you're talking about directing sound elsewhere, this is why we have the "large" monitors set further apart and further back and with wider room separation. If you only have the one set of monitors, maybe you have a point for dispersion etc.

I got the impression that the OP was asking about himself, for himself, working alone with his small system. If my impression was correct then toed in and so on is correct.

imho, ymmv, yadda yadda.
Yeah I think he was haha

I might have derailed it somewhat, sorry guys. I was in a studio at the time that has full scale PMC's etc and it was quite late, so oops!

This might help with the discussion.

http://www.cardas.com/pdf/roomsetup.pdf

I did some measurements in the smaller studio and the monitors are 46 inches apart with the listening position at 60 inches dead centre no toe in. The backs are also about 35 - 40 inches from the back wall and the sides are around 60 inches from the side walls. Good monitoring level in this room was around 80 dbs maybe a bit less, sounded ok when listening from different parts of the room. Didn't get the room dimensions though...

Back to the original question regarding monitoring level, it is worth noting that your monitoring level might depend on the sort of music you are producing, for classical music you need to hear all the dynamics so monitoring level is quite loud, so you can hear the quiet parts easily and can experience the rush of the loud parts. For pop music the level is lower because the dynamics tend to be compressed, more so these days, and you don't want to ruin your hearing producing this at loud levels since it is LOUD all the time.

If you haven't already read them I'd read the book Mixing with your mind and anything by Bob Katz. Also check out http://www.dynamicrange.de/ and the K System for useful insights into loudness and monitoring.
#24
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by dkelley View Post
yes, interestingly enough is right, because putting them on the side means that as you move from side to side the frequency response will change along with introducing phase issues. where as typically it's desireable to keep them vertical because then the horizontal dispersion will only gradually reduce HF dispersion, not alter the entire frequency response through the crossover range as is the case with horizontally set speakers.

sadly I think that pokes a hole in the focal documentation, although they are undeniably one of the greatest driver manufacturers in the world (I have focal tweeters, alone with jbl woofers, in my custom made compact near fields).
<cough> <cough>


Yeah, so not really. The frequency response will change radically no matter which direction you move your head actually (up and down vs. left and right). Since very few monitors are truly "time-aligned" to begin with, the issue of 'phase distortion' is a totally moot point. The directivity of a speaker (especially tweeters incorporating any sort of waveguide on the baffle) is going to be virtually identical on both the vertical and horizontal axes, so it really doesn't matter much at all whether your speakers are horizontal or vertically placed. Plenty of extremely high-end monitors (look at genelec for examples) use a woofer flanked to the left and right with mid-range and/or tweeter drivers. Just because a speaker doesn't employ a pure "vertical line" arrangement of drivers does not in any way mean that it is "poorly designed". That's crazy.
#25
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by dasnub View Post
That is absolutely 100% incorrect. Because high frequencies are more directional than lower ones, you need to have the tweeters pointed at your ears. Read the manual of any respected monitor company and you'll find this to be the case.
The optimum toe-in is speaker (dispersion pattern), room (reflections) and personally (soundstage vs. timbre) dependent. Speaker/listener positions should avoid problematic room modes (low frequencies) first, while still offering a solid soundstage. Then work on toe-in for optimal tonality (brightness) and soundstage intimacy preferences.
#26
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by VDNorman View Post
The optimum toe-in is speaker (dispersion pattern), room (reflections) and personally (soundstage vs. timbre) dependent. Speaker/listener positions should avoid problematic room modes (low frequencies) first, while still offering a solid soundstage. Then work on toe-in for optimal tonality (brightness) and soundstage intimacy preferences.
Bingo, now this is very true. Toe-in can effectively mitigate or exacerbate interactions with the room (and the speaker's inherent response curve) at areas above 2khz or so where most speakers become rather directional.
#27
22nd February 2012
Old 22nd February 2012
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This is a great question hardwinte, but difficult to answer. Like so many acoustical questions, there are many variables that must be considered. In yours, some of the dependent variables that come to mind regarding perception SPL of room modes are:

- Room Dimensions (mode distribution). How close or far apart are they, etc.
- Speaker/Listener locations within the room.
- Room size.
- Room reverberation times (construction, furnishings, acoustic treatments).
- Signal frequency and duration.

Basically, a standing wave can be perceived at a lower SPL than you would typically mix at. The frequency only needs to be divisible by the length, width or height of the room, and play long enough to develop into a standing wave.
#28
22nd February 2012
Old 22nd February 2012
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Quote:
Originally Posted by rifftrax2 View Post
<cough> <cough>


Yeah, so not really. The frequency response will change radically no matter which direction you move your head actually (up and down vs. left and right). Since very few monitors are truly "time-aligned" to begin with, the issue of 'phase distortion' is a totally moot point. The directivity of a speaker (especially tweeters incorporating any sort of waveguide on the baffle) is going to be virtually identical on both the vertical and horizontal axes, so it really doesn't matter much at all whether your speakers are horizontal or vertically placed. Plenty of extremely high-end monitors (look at genelec for examples) use a woofer flanked to the left and right with mid-range and/or tweeter drivers. Just because a speaker doesn't employ a pure "vertical line" arrangement of drivers does not in any way mean that it is "poorly designed". That's crazy.
Time, energy and frequency responses will all change if you move your head vertically or horizontally from between a pair of speakers, regardless of tweeter orientation. However, moving horizontally will have the most effect, which is what engineers do when mixing. Side mounted tweeters exasperate this problem further. Therefore, it is advantageous to have vertically mounted tweeters when mixing.

With side mounted tweeters, the difference in TEF responses between center and just a few inches to one side is not subtle (especially when near-field). Add toe-in with side tweeters and the problem increases. This is one of the most common errors I see when voicing studios.
#29
23rd February 2012
Old 23rd February 2012
  #29
Lives for gear
 

Keeping this simple, use one monitor and move it to a position in the room until the reflections coming from all directions create a flat response. Your biggest problem is gonna be bass, high end is much easier to control. You are after the flattest bass response. Build your studio around this position, if possible...
#30
23rd February 2012
Old 23rd February 2012
  #30
Lives for gear
Quote:
Originally Posted by rifftrax2 View Post
<cough> <cough>


Yeah, so not really. The frequency response will change radically no matter which direction you move your head actually (up and down vs. left and right). Since very few monitors are truly "time-aligned" to begin with, the issue of 'phase distortion' is a totally moot point. The directivity of a speaker (especially tweeters incorporating any sort of waveguide on the baffle) is going to be virtually identical on both the vertical and horizontal axes, so it really doesn't matter much at all whether your speakers are horizontal or vertically placed. Plenty of extremely high-end monitors (look at genelec for examples) use a woofer flanked to the left and right with mid-range and/or tweeter drivers. Just because a speaker doesn't employ a pure "vertical line" arrangement of drivers does not in any way mean that it is "poorly designed". That's crazy.
incorrect. it's simple physics. there are monitors, as with the very bizarre ones you pointed out in that post, that don't work on the same concepts. extreme crossover designs can reduce the audible effect of crossover phase distortion from two drivers outputting the same sound at the same time, but it's not what you find in almost every single monitor ever made.

I stand by my answer, having seen it proven repeatedly for decades.

I also described quite clearly in my previous post why what I said is true, and all you have to do is research this yourself to find that it is true instead of finding one obviously uncommon speaker design and refuting everything I said as a result. The most important thing is that all speakers have a direction, either horizontal or vertical, along which they exhibit much less (possibly zero) difference in phase relationship as you move along that axis.

I'm not talking about "time aligned drivers", which typically means setting the tweeter further back than the woofer. I'm talking about following the rule of point source reproduction, which with multiway speakers that aren't coincidentally mounted (certain "tannoy" etc.) or omnidirectional (some vintage "ohm walsh" models for example) can only exist in one plane, not both.

The science and physics behind what I said is pretty well understood and accepted/proven as fact. If you move your head (or a microphone if you want to test scientifically yourself for some reason) along the plane where tweeter and woofer remain equal distant from the mic/ear (horizontal plane with vertically aligned drivers), you will not hear the extreme inconsistencies in frequency response through the crossover range that you will hear if you move your head along the plane where tweeter and woofer get closer/further away as you move (horizontal plane with horizontally aligned drivers).

Your point about dispersion isn't what I'm talking about. The tweeter only has bad dispersion at it's highest frequencies. At it's lowest frequencies it has EXCELLENT dispersion, and this is precisely why the range of frequencies where both the tweeter and woofer (or tweeter and midrange) are reproducing exactly the same signal is extremely susceptible to audible phase and dispersion problems.

You effectively have your woofer creating, for example, a 5kHz output 3 or 4db down from it's normal level, and your tweeter creating also the same signal at the same frequency and also 3 or 4db down from it's normal level. When combined the two drivers sum the output into as close to an even output level as possible. However because the tweeter is at least a couple of inches away from teh woofer typically, sometimes much more, rarely a little less, you now have a huge problem with phase irregularities between the two drivers. However in the horizontal plane, if drivers are mounted vertically, you will not experience the variations from this that come from moving your head the other way (or mounting the speaker on it's side).

If you don't believe me (as you appear not to), please email genelec and ask them about this topic - pasting in my email if you choose to do so. I would be interested in reading their response.

Actually, I can provide the answer from Genelec right here:

Genelec Community - Tech Tips

"All spaced driver monitor solutions suffer from a notch in the frequency response when listening off-axis in the plane of the drivers. Positioning the monitor horizontally causes this notch to become audible when moving from left to right along the mixing desk. Positioning the monitor vertically removes this problem."




OH - and for genelec, show me the examples please where they aren't vertically aligned. I have used plenty of genelecs and they are ALL vertically aligned. The exception to the rule is their VERY large main systems which only have subwoofers on the sides where phase relationships aren't relevant due to the wavelength and dispersion of low frequency sounds (this is a common design in pro studio main systems - you don't find it in speakers that aren't built into the studio walls typically due to the sheer size of these designs).

Always keep it vertically aligned if possible (I do understand it isn't always practical do to so). It's low hanging fruit - doing it reduces a problem, not doing it increases a problem, it costs nothing, and it improves sound quality in most situations.

At least this should matter to the us if we're a typical engineer who is sitting OR standing most of the time while moving from side to side to adjust things.... or if you have lots members of a band and you want them all to hear things more or less similarly so you get them to all stand or all sit, knowing that no matter where the are horizontally across the room behind you they are all hearing the midrange area more or less the same.
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