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Spatial Mixing Techniques

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This is a bit off topic, but I decided to hijack this thread rather than begin a new one. ;D

When spatial mixing for domestic cd players, cross-referencing in mono is pretty important; considering how many people place their speakers in less than ideal locations, surely hard panning for spatial effects could potentially destroy the effect. Does anyone have any alternative ideas for spatial mixing that would be less of a problem?

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Delay effects. IMO, well used delay can create space in most mixes and on pretty much any system. Particularly if you can high pass filter a final mix/master, and add an amount of verb and delay over the highs. They seem to sharpen up and sound more spacial within the mix and room.

BTW, the question you've asked is much more interesting than you give credit and deserves it's own thread :D

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Sorry it's teacher in me: spatial not spacial - Spacious yes, Spacial no (maybe in America but they don't know how to spell) :D

I posted some audio examples of how delay affects stereo image and sound location here:

http://www.soundpunk.com/index.php?topic=681.0

I gradually increase the delay time in one channel and you can hear how it appears to be 'panning' the sound even though it's not.

There's also some discussion about reverb and its effect on stereo in there - hope it helps :D

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Well my spelling in the thread title was crap, but it seems I was at least self edumacated on the delay front!

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When spatial mixing for domestic cd players, cross-referencing in mono is pretty important; considering how many people place their speakers in less than ideal locations, surely hard panning for spatial effects could potentially destroy the effect. Does anyone have any alternative ideas for spatial mixing that would be less of a problem?

To answer the specific question, I guess we are fighting an uphill battle to compensate for poor speaker placement. We spend hours creating finely crafted stereo tricks, only to have them negated by speakers parked in bookshelves, behind the couch, under the TV, one in the back yard near the barbie while the other is indoors near the pool table... an engineer's nightmare  :dead:

My take on it is that if people set up less than ideal speaker placements, then they really haven't thought about stereo image and actually don't care - as long as it doesn't drown out their conversation, or conversely is cranked loud enough to dance to and party on, then our beautiful tricks of phase and delay are pointless.

My experience has shown that stereo imaging and pan is (a) one of the last things most producers think of until they have accrued enough training and experience to understand its benefits, and (:D something most everyday listeners are intuitively engaged in, but consciously unaware of. They need to be told and shown how stereo works, and even then it can get confusing to them - try asking your mum about stereo image and see the blank response  :wtf:

It seems like a cheap shot, but one solution to the problem is to reduce the amount of spatial effects being used and go for a more mono-ish sound. For most dance music this is fine, if the end destination is club PA's and deaf ravers. For recordings that are made to be listened to, then I think we have to just mix the way we want to, and if listeners have their speakers set up badly it's their problem (although most people won't even notice there is a problem :D )

And we haven't even started on Surround - now there's a system with some problems! 

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Well my spelling in the thread title was crap, but it seems I was at least self edumacated on the delay front!

Give me a 2000 word essay on the topic by Monday and I'll forgive you

:eatadick:

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Don't forget you can use EQ for depth in your spatial mix too. RB covered a nifty tutorial in class that encorperated a lower or dulled top end to create a greater sense of depth in the mix rather than just relying on volume and pan alone. I think RB's class tute was to automate the low-pass threshhold while automating pan and volume,  to create a circular motion type effect in the stereo field. But the same concept (rolling off top end), combined with the an appropriate volume, can be applied to static placements of audio elements as well to create an enhanced sense of depth in the mix. No pan required if you just want to achieve depth. It's all part of the spashessnessnesss of a mix - me thinks.

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^ Indeed (yes its RB, can't be bothered with log-out shuffle :D )

Basic principle of high-frequency air damping present in the acoustic world. Shaving some top end off a sound can help make it sound further away, as if the highs have been absorbed by air mass. More effective when some reverb is added too.

Indded niktu, spaciousness is limited when we are simply moving our sounds in the mix to the left and right - it's still a 2-dimensional soundfield, just sideways. Real 3D effects ensue if we move the sounds back and forth too (and ideally up and down too but in a pair of stationary speakers that's a tricky one - not impossible but tricky :D )

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Thankyou RB and friends,

I suppose what i was thinking of when i started this thread is the L/R front/back position in the soundfield rather than overall depth. One of the channels sent to reverb at least leaves something in the other speaker so u don't get silence. 

Just before I was having a go at some tinny hi-hats and found that a short reverb without predelay filled out the tone a little, then another reverb inserted after that for ambience gave it a better shape. Ground-breaking news, I'm sure.

But in fairness to jester-fu, 'spacial mixing ' will become a pretty hot topic when we start transmitting music to other planets - ie how do we compensate for a a vacuous medium? (We need a little geek icon here!!!)

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hang on, i thought someone said 'spacial' refers to out of space. My god, I'm hallucinating again.

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But in fairness to jester-fu, 'spacial mixing ' will become a pretty hot topic when we start transmitting music to other planets - ie how do we compensate for a a vacuous medium? (We need a little geek icon here!!!)

Thankfully radio waves can transmit in a vaccuum so maybe our alien friends can enjoy Kyle and Jackie-O on the Fox like the rest of us  :D

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Thankfully radio waves can transmit in a vaccuum so maybe our alien friends can enjoy Kyle and Jackie-O on the Fox like the rest of us  :P

Hang on! ISAMod's not allowed to make funneh's  :D

... just as well it wasn't funneh ;)

Edit 0- Oops - just realised I've had the SP tab open all day at work since 10am. Hope ITS aren't spying... although it's now legit...

http://www.soundpunk.com/index.php?topic=2322.msg25396#new

:D

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But in fairness to jester-fu, 'spacial mixing ' will become a pretty hot topic when we start transmitting music to other planets - ie how do we compensate for a a vacuous medium? (We need a little geek icon here!!!)

I guess in fairness to you, you don't really understand how radio transmission works. Stereo field makes no difference as the signal is sent based on a carrier wave and different encoding technologies. The one you'd be most familiar with is Frequency Modulated where the carrier wave frequency is modulated by the source signal.

More commonly used in transmission of signals into space - say to the Mars rover or space shuttles or any one of the thousands of satellites orbiting the earth - are based around PSK (Phase Shift Keying) and QPSK (Quadrature Phase Shift Keying). QPSK is a very efficient transmission protocol as it allows a minimum of 4 seperate states per carrier wave. These are all based around the phase quadrant and amplitude of the carrier to get data across. The more accurately you can phase lock, the more info per quadrant and the more info transmitted per carrier base. While you can transmit analogue source signals using these protocols, it's generally more efficient to transmitted encypted digital information.

So, long term, the issue of transmitting information to space is less 'spatially' dependent than using the analogue technologies commonly applied on Earth. Paning and phase is no more of an issues for music transmittal into space than it is for recording onto a CD.

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how do we compensate for a a vacuous medium?

Excellent question. I think this issue was addressed in Star Trek episode #36,472  - something to do with a sub-space field, two match sticks at either end of a banana and Mr Data's positronic brain.

Sorry for not explaining myself better in my EQ suggestion, EM. When I was referring to depth, I was referring to front/back placement. I should have mentioned that somewhere. Let's just mind-meld next time. Way easier.

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I guess in fairness to you, you don't really understand how radio transmission works.

I was actually thinking about live shows and pa systems, i think i used the word 'transmit' because it sounds geekier.

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A trick i learnt that seems to work in mono as well is to:

1. Take a split of the mono signal and pan one left and one right.

2. Run the split through a graphic eq  and alternatively boost one freq starting at 200hz +12 or +16dB then the next band all the way down by    -12 or -16dB then the next all the way up until you reach the end of the graphic.

3.Pull all the freq below 200hz down to protect your speakers.

4.Then delay that signal between 5msec to 18msec ( to what sounds best ).

Try it it works.

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To answer the specific question, I guess we are fighting an uphill battle to compensate for poor speaker placement. We spend hours creating finely crafted stereo tricks, only to have them negated by speakers parked in bookshelves, behind the couch, under the TV, one in the back yard near the barbie while the other is indoors near the pool table... an engineer's nightmare 

never thought i'd say this - thank god for iPods/Discman/Walkman!

bout the only time you can be certain there is a consistent sound-stage to work with (unless 2 14yo girls are listening on the train with a bud in each ear - but hey, if they're listening means you've made it and have a pro to worry about the engineering!)

edit: actually, this has made me think a little - from now on, my music is to be only heard thru Sennheiser HD25's or in my studio's mix chair.

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