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Gear / Technical Help => Post-Processing, Computer / Streaming / Internet Devices & Related Activity => Topic started by: jb63 on January 31, 2018, 01:27:15 PM

Title: 4 stereo channel mixing
Post by: jb63 on January 31, 2018, 01:27:15 PM
OK, this is a weird post.
Lately I've been linking 2 ocmR44s together and for the most part it syncs up just fine.
Then I get 4 stereo channels all lined up, but I've been using Sound Studio on an old mac to do the mixing. That lets me paste any % of any channel into another, but it doesn't let me turn the knobs in real time to, say, add a bit more omni into a card source while listening. All I can do is know what I want beforehand and make the mix then listen back and see how it sounds.

Here's an example:

http://www.mediafire.com/?uv6pswmtt9c9a

(they sound much better in a deeper bit depth, but you'll get the idea.)

I can't seem to get the mix I want out of these, but all I can do is paste various % amounts into other amounts and see how it sounds.
What I WANT to do is have a program (that works on a mac) that I can load all 4 stereo channels into and then turn the knobs to the amount I want to hear from each channel and finalize the mix.

As a kind of desperate measure, I was even thinking that if I had a unit (I was thinking an F8) that would allow me that option on playback, I could just mix it down after the show and record a final mix in real time to through the line-outs, but that seems wrong in this day and age. There has to be a software solution.

Thanks! Any info is good info!

Title: Re: 4 stereo channel mixing
Post by: nulldogmas on January 31, 2018, 01:35:32 PM
As a Mac/Sound Studio user with the same frustration, I second this request!
Title: Re: 4 stereo channel mixing
Post by: heathen on January 31, 2018, 01:46:29 PM
If I understand what you have in mind, I think this can be done with Audacity.  You can have the four individual tracks on the screen, and each track has its own slider bar for gain that you can adjust while you listen.
Title: Re: 4 stereo channel mixing
Post by: noahbickart on January 31, 2018, 01:52:51 PM
All you need is a multitrack editor. Sound studio is really a stereo only editor. I use reaper, which is fairly inexpensive, and while the learning curve is steep, it is really powerful.

Others are able to do with ease what you want with Audacity, which is free.
Title: Re: 4 stereo channel mixing
Post by: nulldogmas on January 31, 2018, 03:56:27 PM
Clearly I need to explore Audacity's functions more carefully. Thanks!
Title: Re: 4 stereo channel mixing
Post by: rippleish20 on January 31, 2018, 03:58:57 PM
I'm a Mac user and I use Sound Studio. For mixing try Reaper.
Title: Re: 4 stereo channel mixing
Post by: Sloan Simpson on January 31, 2018, 04:16:52 PM
Reaper
Title: Re: 4 stereo channel mixing
Post by: Gutbucket on January 31, 2018, 04:41:40 PM
I've been using Sound Studio on an old mac to do the mixing. That lets me paste any % of any channel into another, but it doesn't let me turn the knobs in real time to, say, add a bit more omni into a card source while listening. All I can do is know what I want beforehand and make the mix then listen back and see how it sounds.

I can't seem to get the mix I want out of these, but all I can do is paste various % amounts into other amounts and see how it sounds. What I WANT to do is have a program (that works on a mac) that I can load all 4 stereo channels into and then turn the knobs to the amount I want to hear from each channel and finalize the mix.
^
Just posting to confirm that is what you really need to do when mixing multiple source channels.  It's absolutely critical in my opinion.  Jump on a multitrack editor such as Reaper or Audacity or something else as suggested.  Connecting your ear to your knob turning (err, mouse-moving) hand in real-time will make all the difference in the world.

Quote
As a kind of desperate measure, I was even thinking that if I had a unit (I was thinking an F8) that would allow me that option on playback, I could just mix it down after the show and record a final mix in real time to through the line-outs, but that seems wrong in this day and age. There has to be a software solution.

Yes, the best solution is a software multitrack editor, but nothing wrong with doing via the hardware you already have.  I do this frequently when I don't have an editing machine available (currently). 

I use my OCM R44 to mix down 4-channels to stereo and record the SPDIF out to another machine.  This provides "real-time" level control of all four channels.  Unfortunately it does not allow for panning.  Channels 1&3 are always routed Right and chs3&4 are always routed Left.  Exception is if using the Mid/Side playback effect on one or both channel pairs, which pans ch 1 and/or ch 3 to center.  You can then either ignore its channel pair (100% Mid) which lets you do a 3 channel L/C/R mix to stereo, or to use channels 2 and/or 4 as side channels, routed ti both Left and Right with polarity inversion to the right side.  Alternately you can use the EQ or other functions instead of Mid/Side but they cannot alter the ch1 and 3 hard-Left, ch 2 and 4 hard-Rght panning.

I also do the same with the Tascam DR-680.  It allows for panning and level control over all 6 channels in the mix down to stereo, was well as Mid/Side decoding on channel pairs, but provides no EQ.  Like the R44, the DR-680s stereo output can be analog via the RCA line-outs or headphone jack, or SPDIF.

If you record the SPDIF stereo output from either of these machines you've not done any DAC/ADC conversions.  The signal path through to the stereo mixdown file remains digital.

The Zoom and Sound Devices recorders provide more monitor/mixdown controls, with control over level, pan, mid/side, EQ, polarity, and delay I think per channel.  I think all of those are limited to 4 channels out only, but that's not a limitation for mixing to 2-channel stereo.   Some don't have a digital output (I don't think the Zoom does) so you'd need to output analog and re-digitize that, which is probably fine.  Not sure if they allow mix down within the machine to their stereo file from the individual ISO tracks after the original recording has been maid or not.  If so that would be the way to go if doing it this way.  The DR-680 cannot do that.

This all works fine, sounds fine, provides the needed capabilities, and is fun to figure out, but is not nearly as flexible as a software editor.   Its nice to be able to do this in a pinch, but a software editor is the best answer.
Title: Re: 4 stereo channel mixing
Post by: danny3 on January 31, 2018, 04:43:57 PM
If you have never done a multi-track mix before, I'd highly recommend trying Audacity. It is free, easy, and will give you some exposure to the process.  I can’t imagine attempting to do it the way you describe above, just thinking about it spins my mind!
Title: Re: 4 stereo channel mixing
Post by: jb63 on February 01, 2018, 03:01:21 PM
Well audacity was a charm!
I've had it for years but never liked the interface. Had to get the new version just to make it work, but YES! I was able to get what I wanted in 5 minutes!
I don't know how well it will do with 4 stereo 2496 channels-- especially if you want to do a whole 2+ hour show, but i could live with saving a preset and doing it track by track.

Even with the R44's perfectly-synched files, mixing them the way I was in sound studio often created milliseconds of drift that rendered hours of work useless.

So I think this is definitely the way to go!

Audacity greatly improved the clarity of this one in no time and let me get just the right amount of dpa4021 bass into an already perfect dpa4061 capture!

http://www.mediafire.com/file/6ilahrdo2ok61ma/Party%20Liquor%20audacity%20hybrid.flac
Title: Re: 4 stereo channel mixing
Post by: Gutbucket on February 01, 2018, 03:45:48 PM
Great!  Very pleased this immediately worked out well for you. Thanks for the follow up post.

Nice bottom on your sample.  If interested in any EQ tweaking, I found a slight EQ correction tamed the slight brightness in my brief listen to your sample .  I cut 1k ~-1dB, 6k ~-.5dB, and 12k ~-1.5dB, leaving 3k untouched to retain good vocal clarity.  My hand-waving- that's off-the-cuff, subjective, may be headphone dependant, etc, but its not out of line with what I find commonly helps 406x recordings.

Title: Re: 4 stereo channel mixing
Post by: nak700s on February 01, 2018, 05:54:00 PM
Yup, I agree.  Audacity is what I use and it works well with my 4-channel recordings. 
Title: Re: 4 stereo channel mixing
Post by: jb63 on February 02, 2018, 02:53:12 PM
Great!  Very pleased this immediately worked out well for you. Thanks for the follow up post.

Nice bottom on your sample.  If interested in any EQ tweaking, I found a slight EQ correction tamed the slight brightness in my brief listen to your sample .  I cut 1k ~-1dB, 6k ~-.5dB, and 12k ~-1.5dB, leaving 3k untouched to retain good vocal clarity.  My hand-waving- that's off-the-cuff, subjective, may be headphone dependant, etc, but its not out of line with what I find commonly helps 406x recordings.

Yay!
Advice is what I like. I may not have the time to get back to this soon, but I will eventually. I just got hit with over $3000 of emergency cat surgery. Ow! So I have to scare up some new gigs pronto.

Meanwhile, it looks like all of those settings are easy to find in audacity! So that's great. I just wish it wasn't blue.

There's a weird "Charlie Miller" part of my personality that really wants to be able to get that capture right and perfect in my seat so that the live recording can just be played back-- you know, like we did on cassettes-- but I realize that's not really the direction this hobby, er... obsession, has taken. Almost to the point where post-processing is the point of every capture. But I really would like have field unit about the size of an F8 that I could record a bunch of stereo channels onto an SD card with, then play back from that card turning the knobs for each channel to add that into the mix. Every time I listened back I could do a different mix, and eventually I might decide to mix down one of them to 2 channels in real time.

Then I guess label & keep the card like it was a cassette or DAT master and get a new card for the next show.

How unreasonably expensive would that be?

You certainly couldn't do it with an R44, but maybe the new mixpre series could pull that off.

Running an MR1 (or 2) has taught me the joys of getting it right within the first minute because playback of DSDIFF files it really a no-editing process. I guess I got spoiled.



Title: Re: 4 stereo channel mixing
Post by: nak700s on February 02, 2018, 04:22:03 PM
Great!  Very pleased this immediately worked out well for you. Thanks for the follow up post.

Nice bottom on your sample.  If interested in any EQ tweaking, I found a slight EQ correction tamed the slight brightness in my brief listen to your sample .  I cut 1k ~-1dB, 6k ~-.5dB, and 12k ~-1.5dB, leaving 3k untouched to retain good vocal clarity.  My hand-waving- that's off-the-cuff, subjective, may be headphone dependant, etc, but its not out of line with what I find commonly helps 406x recordings.

Yay!
Advice is what I like. I may not have the time to get back to this soon, but I will eventually. I just got hit with over $3000 of emergency cat surgery. Ow! So I have to scare up some new gigs pronto.

Meanwhile, it looks like all of those settings are easy to find in audacity! So that's great. I just wish it wasn't blue.

There's a weird "Charlie Miller" part of my personality that really wants to be able to get that capture right and perfect in my seat so that the live recording can just be played back-- you know, like we did on cassettes-- but I realize that's not really the direction this hobby, er... obsession, has taken. Almost to the point where post-processing is the point of every capture. But I really would like have field unit about the size of an F8 that I could record a bunch of stereo channels onto an SD card with, then play back from that card turning the knobs for each channel to add that into the mix. Every time I listened back I could do a different mix, and eventually I might decide to mix down one of them to 2 channels in real time.

Then I guess label & keep the card like it was a cassette or DAT master and get a new card for the next show.

How unreasonably expensive would that be?

You certainly couldn't do it with an R44, but maybe the new mixpre series could pull that off.

Running an MR1 (or 2) has taught me the joys of getting it right within the first minute because playback of DSDIFF files it really a no-editing process. I guess I got spoiled.

I'm all about getting it right while at the show too, but with multi-track recordings, it's a different world.  A 2 channel recording can be utilized the way you described, but more than 2 is another story.  With the right equipment, you can get very close, if not exactly the way you want, with some practice and experience, but it still needs to be played back with something that handles multi tracks.  I use a Sound Devices 744T, and I'm very happy with the results I get from that (Zoom equipment is not on my radar, so I can't answer anything about them).  A 788T will offer you the same, but with the ability to record with more mics (inputs).  I run 4 and 5 channel recordings all the time (running 3 mics into the SD 302 pre-amp) and Audacity is how I mix, blend, listen...edit, and make 2 channel recordings with.  I don't keep the cards (they're compact flash cards in the 744T). but I do keep all tracks as I originally recorded them, as well as the process that gets me to the 2 channel.  I store them on external hard drives, and back them up for piece of mind.  I believe you could do the same with the Mix-Pre series as well.
I'd recommend taking one of your multi-track recordings and experimenting with it.  You'll determine, based on the way you record, which tracks to raise, which to lower and to what level to put them at before tweaking.  It's overwhelming at first, but like anything else, once you get the swing of it, you'll move through it much easier.  Enjoy!
Title: Re: 4 stereo channel mixing
Post by: Gutbucket on February 02, 2018, 04:27:03 PM
There's a weird "Charlie Miller" part of my personality that really wants to be able to get that capture right and perfect in my seat so that the live recording can just be played back-- you know, like we did on cassettes-- but I realize that's not really the direction this hobby, er... obsession, has taken. Almost to the point where post-processing is the point of every capture. But I really would like have field unit about the size of an F8 that I could record a bunch of stereo channels onto an SD card with, then play back from that card turning the knobs for each channel to add that into the mix. Every time I listened back I could do a different mix, and eventually I might decide to mix down one of them to 2 channels in real time.

Then I guess label & keep the card like it was a cassette or DAT master and get a new card for the next show.

How unreasonably expensive would that be?

You certainly couldn't do it with an R44, but maybe the new mixpre series could pull that off.

Running an MR1 (or 2) has taught me the joys of getting it right within the first minute because playback of DSDIFF files it really a no-editing process. I guess I got spoiled.

Getting it right from the start is always best to the extent that it is practical to do so!

However, once we start mixing multiple mics together, like it or not, the resulting recording is then dependent on our subjective post-recording mix decisions.  EQ should be used cautiously as it can do more harm than good due to the deficiencies of our monitoring and our own listening skills/attention/fatigue while making those decisions, but its simply another subjective post-mix decision similar to what the proper ratio between sources should be.  Albeit a  somewhat more advanced one.

No reason you can't do this with an R44.  You just need a second recorder to capture the resulting 2-channel stereo file.  And a written record of what mix decisions you made for reference the next time.  You can do so for a maximum of four recorded channels, with control over level and EQ control (or Mid/Side control), you just can't change the panning of the originally recorded files from chs1,3>Left and chs2,4>Right. Ideally you'd want the mix-down recorder to have SPDIF input to avoid D>A>D conversion in between machines.  But you could mix down via the analog outs to a cassette deck if you wanted.

You might even be able to do the same for 2 linked R-44's (8 channels total).  You'd need to go analog-out instead of SPDIF-out to do that, then sum either all 8 individual channels or the 2 stereo-output pairs from each playback machine externally somehow prior to your stereo mix-down recorder.

Like the DR-680, I don't think the Zoom or the SD MixPre machines allow re-recording of a stereo mix during playback.  All of them will let you record a stereo mix on-the-fly while making the original recording, but not while playing back that original recording again while tweaking things.

And, I know it's not what you meant but I must add- Charlie ain't weird! He's cool!  (Although we may disagree on post-processing in "big picture" terms, I agree that his philosophy is best with respect to the massive legacy of his GD matricies - primarily because he's dealing with historical recordings made by other folks.  But for one's own recordings, I say do what you feel results in the best experience for the listener, but be careful and check your work to make sure you aren't deceiving yourself in the process.)
Title: Re: 4 stereo channel mixing
Post by: jb63 on February 04, 2018, 07:36:20 PM
If interested in any EQ tweaking, I found a slight EQ correction tamed the slight brightness in my brief listen to your sample .  I cut 1k ~-1dB, 6k ~-.5dB, and 12k ~-1.5dB, leaving 3k untouched to retain good vocal clarity.  My hand-waving- that's off-the-cuff, subjective, may be headphone dependant, etc, but its not out of line with what I find commonly helps 406x recordings.

Thanks, Gutbucket!
So just for fun I popped this sample into audacity and tried to make some sense of your notes, and for the life of me, I couldn't figure out how to do that. I'm sure I am missing some audio engineer speak. I did find the EQ, and found many ways to turn the knobs, so to speak, but I can't even remotely understand how I would "cut 1k ~-1dB, 6k ~-.5dB, and 12k ~-1.5dB, leaving 3k untouched" even though it seems so easy as I type it, I have no idea what you are saying! I had to come back and tell you because I really, really feel stupid and like I should sell all my gear and give up.

I might actually just be going crazy.
Title: Re: 4 stereo channel mixing
Post by: beatkilla on February 04, 2018, 08:24:19 PM
If interested in any EQ tweaking, I found a slight EQ correction tamed the slight brightness in my brief listen to your sample .  I cut 1k ~-1dB, 6k ~-.5dB, and 12k ~-1.5dB, leaving 3k untouched to retain good vocal clarity.  My hand-waving- that's off-the-cuff, subjective, may be headphone dependant, etc, but its not out of line with what I find commonly helps 406x recordings.

Thanks, Gutbucket!
So just for fun I popped this sample into audacity and tried to make some sense of your notes, and for the life of me, I couldn't figure out how to do that. I'm sure I am missing some audio engineer speak. I did find the EQ, and found many ways to turn the knobs, so to speak, but I can't even remotely understand how I would "cut 1k ~-1dB, 6k ~-.5dB, and 12k ~-1.5dB, leaving 3k untouched" even though it seems so easy as I type it, I have no idea what you are saying! I had to come back and tell you because I really, really feel stupid and like I should sell all my gear and give up.

I might actually just be going crazy.

Jb63 try getting this book I think you will learn a few tricks
https://www.amazon.com/Audio-Post-Production-Your-Project-Studio/dp/1598634194