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New user has questions regarding making 5.1 out of four separate channels

To start with, let me say that I am a noob to this and not an audiophile person.  I do not have that experience.  But, what I am trying to do is capture my father playing the piano.  He is in his mid-70's and has agreed to let me setup some equipment around his grand piano, so that I can capture him playing, before he is either gone or no longer able to play like he does now.

So, in that light, let me give some background.  I have two of my own Canon 5D3s running Magic Lantern (so  that I can get a continuous HDMI output feed that doesn't stop at 30 minutes) that I intend to put on tripods and just have them run in Live View mode.  One will capture his hands on the keyboard, while the other will be a 3/4 shot of him playing.  The output (HDMI) of the camera will be going to two different PC's with video capture cards in them, recording 1920x1080p at 24 fps.  I also have a Canon HD G30 camcorder that I plan to "roam" with during his recital.

For audio, I have two Tascam DR-10SG microphones that will be tripod mounted, one on either side of the keyboard, just above the edge of the piano, pointed at the strings.  These are mono-devices and I plan to make them my "rear" speakers.  I also have a tripod mounted Tascam DR-40 that will be placed at the far end of the piano, again, just above the edge, pointed at the strings.  The output from the DR-40 will be my main left/right channels.

What I would like to do is in post, somehow create a 5.1 output.  I am using Adobe products (I subscribe to their entire CC package) and plan to edit in Adobe Premiere Pro.

So, my questions are:

1) What is the best way to take my current setup and "create" a center channel, without adding another microphone?  Is that realistic?

2) How do I create the ".1" output for output to the sub-woofer.  Is there specific software that I need to get to do this or does my current Adobe suite handle this?

I am not specifically asking for someone to provide step by step directions, but searches did not turn up what I am trying to do.  Any help here is greatly appreciated.  This is a project that has been in the back of my mind for some time now and, now that I am retired, it is time to make it happen.  So, if anyone has any input or insight into what I am trying to do and can help me in creating the final product, I would be immensely grateful.  My end-state goal is to have a BluRay disc with about two hours of recording on it, all in HD and all in 5.1, if possible.  Thank you for taking the time to read this and I thank you in advance for any help anyone can provide.

Scott


Re: New user has questions regarding making 5.1 out of four separate channels

Reply #1
The LFE channel can be captured with yet another microphone or extracted from low-pass filtered mixes of your existing channels. The trick is to capture the low frequencies were they are most apparent, so sticking a microphone under the piano is probably not the best idea. Low frequencies cannot really be located by human hearing, hence the location of the subwoofer isn't really much of an issue either. Wherever you get the best decent signal from, is fine, as long as it sounds alright when reproduction happens.

The five main channels are usually recorded with contraptions like these:

http://www.2l.no/media/2L-086_rec-session_microphones01.jpg
http://www.2l.no/media/2L-086_rec-session_microphones02.jpg

Also this: https://www.researchgate.net/profile/Bozena_Kostek/publication/272536405/figure/fig1/AS:441412463403009@1482252340326/Fig-1-Microphone-placement-in-the-INA-5-system.ppm

You can find loads of these sort of setups, but they all include a five-microphone contraption, so I don't know if you're OK generating center from the other channels.

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #2
Not exactly what you are looking for, but if you want to do it in post, I'm very fond of that "Free Surround" plugin in Foobar2000 and the "Matrix Mixer" (individual volume control for channels, etc) plugin. If you don't want to become an audio engineer for this project, doing everything by hand, I'd recommend using this or something similar. With both of those plugins you have a lot of sliders and settings to fiddle around with until you get the best sound for your use-case.

Maybe there's something similar for Adobe. Certainly Dolby also has automated solutions for this problem.

Just my 2 cents from a layman.

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #3
So many issues... 

Recording piano (or any acoustic instrument) is not easy and I suggest you read as much as you can find about it (especially microphone placement) before you start.   Then make a couple of test-recordings to test & refine your technique.

What kind of room do you have?   I think you're 'nuts' to record surround sound unless you're in a music hall!  ;)     If you have a "dead" room/studio, you can add artificial reverb to the rear channels.*  

Quote
1) What is the best way to take my current setup and "create" a center channel, without adding another microphone?  Is that realistic?
The center can be created by simply blending left & right.    You'll probably want to keep the center volume down a bit so you don't destroy the stereo image, but just go by-ear when mixing.   (Virtually all single-instruments, including piano, are "mono"...   Making a stereo piano recording is a creative process...  When you're sitting in the audience you can't perceive the low & high strings coming from different locations.)

Quote
2) How do I create the ".1" output for output to the sub-woofer.
Don't use the .1 channel, or make it silent.  It's the LFE channel for low frequency effects  ("booms & explosions").   The normal bass goes in the 5 surround channels.    On most home theater systems with "small" surround speakers, "bass management" routes the bass from the 5 surround channels to the subwoofer, along with the LFE channel.  And, when you play a 7.1 or 7.1 channel recording on a 2-channel stereo system, the LFE is not included in the downmix.

Quote
For audio, I have two Tascam DR-10SG microphones that will be tripod mounted, one on either side of the keyboard, just above the edge of the piano, pointed at the strings.  These are mono-devices and I plan to make them my "rear" speakers.
That might be a problem.   Each "device" has it's own clock and the clocks will drift out-of-sync over time.   If both mics are picking-up the same sound the tracks can drift in-and-out of phase creating a weird effect.   The "phasing" can be particularly problematic when mixing down from stereo to mono or from 5.1 to stereo.   In extreme cases, the timing/tempo can get out of sync (especially over a 2-hour "concert") but I wouldn't expect that in your situation.      (Pros use a multi-channel audio interface and/or a master clock along with interfaces with master-clock inputs.)

Quote
My end-state goal is to have a BluRay disc with about two hours of recording on it, all in HD and all in 5.1, if possible. 
Of course, you'll need a video editing application and you'll need Blu-Ray authoring software (which may be included with your video editor) to make a proper-compliant Blu-Ray.    (But, most Blu-Ray players can play a variety of audio/video files so you may not "need" a proper Blu-Ray or DVD disc). 



* If you are going to make "artificial" surround, it's often better to make a stereo recording and then use a Pro Logic II "soundfield" setting to generate surround during playback.

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #4
I would like to thank all those that responded with comments and ideas.  I realize that this is quite an undertaking and the audio result is likely to be less than perfect.  Yet, I must do the best that I can.  Neither of my brothers have shown any interest in this project and seem comfortable letting his music go away when he does.

I intend to "practice" my technique several times before we actually do this live.  I realize that in a performance hall, the sound emanating from a single piano would appear as a single source and not stereo.  But, I have the microphones and want to at least record as many channels as possible.  In the end, I may simply put out a single stereo output, I simply don't know yet.

With regard to microphone clocks drifting, it is my intention to keep him to 30 minute sessions or less and then combine them in post.  A simple clap or clap-board at the beginning of each "session" should help me align the audio (at least that is my hope).  All of the microphones will be mounted on their own tripods and will be elevated to be just above the edge of the piano, pointed directly at the strings.

I am fortunate to be able to retire early and take full advantage of this time.  If anybody else has any ideas with regard to audio mixing, other than Adobe products, please let me know.  I am open to any and all suggestions that will make this effort go smoothly and minimize my time in post.

Again, thank you all for your responses.  You have given me some good things to think about and to take into account.

Scott

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #5
Just a suggestion...  I've recorded piano quite successfully with just two mics, stereo.  It's a whole lot less complex, and you can create "ambience" channels for rear if that seems like a good idea. You loose all of the strangeness of time delay, etc. 

I would also suggest that the normal stereo mic placement for piano is really 90 degrees from what you suggested. Left mic at the right end of the keyboard, right mic at the other end of the piano... That way the piano stretches across the stage the way it does at a performance...

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #6
Just a suggestion...  I've recorded piano quite successfully with just two mics, stereo.  It's a whole lot less complex, and you can create "ambience" channels for rear if that seems like a good idea. You loose all of the strangeness of time delay, etc. 

I would also suggest that the normal stereo mic placement for piano is really 90 degrees from what you suggested. Left mic at the right end of the keyboard, right mic at the other end of the piano... That way the piano stretches across the stage the way it does at a performance...
Thank you for the suggestion.  I intend to try multiple setups while he is "practicing" so that I can get the optimal audio recording.  It is in his home, in the family room, so background noise is going to be present.  I am not trying to pull off a professional level recording (video or audio), but simply trying to capture good quality of both for posterity.

My final question (really is final) is this: Does anyone have experience using Adobe products for post-production of both sound and video?  I subscribe to the entire cloud based set of applications and was wondering if I have enough tools for post-processing or if I should use something different, especially for the audio.  Again, any and all help is appreciated!

Scott

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #7
I've only ever used Adobe Premiere, Adobe Photoshop, and Adobe After Effects. I also had access to the Adobe typography suite. I never used Adobe for audio engineering type of work.

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #8
The Adobe stuff should work fine for you. I have used the GoldWave products, which are inexpensive and easy to use for both audio and video projects.

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #9
Again, thank you to everyone who so kindly replied and didn't give me a hard time about "you should have searched"!  This little project is very important to me and I want to make sure that I capture it as best as I can.  I realize it is not in a concert hall, but in his living room.  I will have to adjust the gain on the microphones to account for that.  My end goal is to get a good (not movie quality, but good) video of him and an even better recording of the piano.  I want to get about two hours worth of recordings, and he is not going to sit still for that long, so I am going to have to do it over several weekends.  And, although he does play beautifully, since he knows he is going to be recorded for this, he wanted some time to "practice".  I plan to use that time to try out different camera and microphone placements.  So, again, thanks to all of you who replied to a newbie and I will report back on my successes (and failures).  If he allows, I may even post a clip of it on youtube for sharing.

Scott

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #10
I worked in audio post-production for TV for about 30 years, mainly on documentaries. In the last few years most programmes were mixed in 5.1, but we very rarely had 5.1 music supplied. In that situation we would add a tiny bit of delay and reverb to feed the rear speakers. Music was never sent to the centre channel, but very occasionally used in the Lfe channel for dramatic effect. As one of the replies already noted, the "Lfe" is for Low-frequency effects", and is a different thing from low-frequency speaker management.

One reason you might put some of a piano recording in the centre channel is if your film is showing in a full-size cinema/theatre. The physical width of the room means you may need to fill the middle a bit! For domestic playback, there really is no need to put anything in the centre.

It just occurred to me that if you used 3 mono mics across the sound-stage, then you'd have an ideal case for using the centre channel! A further 2 ambience mics will give you the surround.

 

Re: New user has questions regarding making 5.1 out of four separate channels

Reply #11
Scott,

I see your letter was published in the January issue of Recording Magazine!

 
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