You are here

Recording on Different Channels?

For current or would-be users of Apple Mac computers, with answers to many FAQs.

Re: Recording on Different Channels?

Postby desmond » Sun Aug 12, 2018 11:52 pm

Ok, I did a little test to see how Loopback works.

My test goal, have two audio sources, iTunes & Spotify, get sent via Loopback into Logic (my DAW of choice), with the stereo feed of iTunes being recorded to one stereo track, and a stereo feed from Spotify to a separate stereo audio at once.

The procedure:
- Run ITunes & Spotify
- In Loopback, add iTunes and Spotify as audio sources to be piped through Loopback. Tick "Mute audio sources" and untick "Monitor" checkboxes (we'll be monitoring via the DAW).

Now, by default Loopback will mix the audio sources into a stereo (2 channel) mix of all the sources. We do not want this, as I want to be able to record the individual audio feeds to individual tracks in my DAW. So:-

In "Channel Mapping", set this to Manual. At this point, the "Left" and "Right" channels will appear to the right of the sources in the source table. In the Channel Mapping table, hit the "+" icon twice to create two more audio channels (four in total, for our two stereo feeds).

Drag the blue "Left" channel from the iTunes audio source, to the "1 (Left)" output channel, and the "Right" to the "2 (Right)" output channel, and then the same for the Spotify left and right, to channels 3 and 4.

Ok, now, with both apps playing, iTunes is being sent to Loopback channels 1+2, and Spotify to Loopback channels 3+4.

Image

Ok, that's our Loopback config done.

- Run the DAW (Logic here), and choose "Loopback" as the input audio device for Logic.
- Create a stereo track, and set it to Input 1+2 (our iTunes feed).
- Create a stereo track, and set it to Input 3+4 (our Spotify feed).

You can now record/input monitor, and see the two stereo feeds going to the correct track. Works great (this is why virtual audio devices are so useful!)

Ok, so back to the OPs setup. What I would suggest is to add *all* your required audio sources in Loopback, including your mic (or audio interface where your mic is coming in from, depending on your hardware). Then make sure you create as many Loopback channels as necessary to pass all the individual audio feeds you require for each audio source.

Then set Loopback as the audio input device in your DAW, and choose the correct audio input/s for each feed on an appropriate track. Hit record, and you are recording all your individual audio channels into individual tracks in your DAW.
User avatar
desmond
Jedi Poster
Posts: 9559
Joined: Tue Jan 10, 2006 1:00 am
mu:zines | music magazine archive | difficultAudio

Re: Recording on Different Channels?

Postby desmond » Mon Aug 13, 2018 12:54 am

And if you don't want to use a DAW to do the actual recording (or want a secondary backup recording), in this example (following on from the test in the above post), I'm using Audio Hijack to do the recording:

Image

The top line is sending Loopback channels 1+2 (iTunes) to a stereo AIFF file, and the second line is sending Loopback channels 3+4 to a separate stereo AIFF file. Or you can just hijack the output of the individual apps and record directly to their own files.

These files can be loaded into a DAW/whatever for editing later.

You can also using Audio Hijack insert plugins, control levels, send to at internet broadcasting server, and use their Farrago app to feed in sound clips, theme tunes, jingles/stings etc in realtime into your audio - it's all very flexible.

Taking it further:

Image

Here we're dong the same thing, recording the two feeds to their own files. We're also taking those two feeds, increasing the volume of one of them, mixing them together and running a compressor plugin on them, and recording the combined mix as a reference mp3 file, while simultaneously broadcasting this to the internet for a live feed of the recording session (this is now quite common where podcasters broadcast a live feed of the recording that their audience can listen to, before the edited version is released a few days later...) - all in realtime.

I love the Rogue Amoeba apps. Loopback is way nicer than using Soundflower, albeit a little pricey. It's also a somewhat more solid way of creating aggregate audio devices than the system way, for apps like Logic that can only specify one device for audio input... Very cool. :thumbup:
User avatar
desmond
Jedi Poster
Posts: 9559
Joined: Tue Jan 10, 2006 1:00 am
mu:zines | music magazine archive | difficultAudio

Re: Recording on Different Channels?

Postby audio_jungle » Mon Aug 13, 2018 3:20 am

desmond wrote:Edit: Ok, I had a look, and it looks like Loopback can hijack applications' output using the same technique as AH, which is great - it means any app can be piped into your Loopback device. You should be all set with Loopback.

Have you listed out your requirements anywhere, and the sources and apps you plan on using?
Do you want to record to individual track per source, so you can maximise your editing flexibility, or do you just want to record to a mixed file quickly without needing to edit the raw individual recordings?

Well, being new to all of this, there are lots of unknown unknowns...

Here is what I have and know so far...

I dropped about $2,000 two years ago on professional mics, a mixer, cables, rigs and a Portabooth. All of this has sat idle since I bought it due to life issues getting in the way.

I have two dynamic and a condenser XLR mics. I have a portable 2 channel audio interface - forget what it is. And some hardware signal "booster" thing. And a nice pair of Sony MDR 7506 headphones.

To record my voice, I will use either the dynamic or condenser mic.

I expect to want to have background music and special effects, so I'll use VLC or iTunes for that.

To interview people by phone, I will use Zoiper.

If I need to interview multiple people or have like a conference call, Zoiper Pro supposedly handles that, but I'm not sure.

Everyone uses Skype, but that seems dirty to me as a Mac user.

I would prefer to use Audacity in the beginning since it is free and I am familiar with it at least as far as basic editing of music I record.

I might upgrade to Hindenburg as I hear it is good for NPR type work.

I think that's it!

For a final product, I want something that sounds like NPR or other similar educational shows.

Seems like this should be fairly easy to achieve, although I can see that hooking up all of the plumbing is a real "audio jungle"! :D

I am willing to do a deep dive on learning proper sound engineering, but I need to get my podcast live in the next few months, so anything or anyone who can help me fast-track things would be a real life-saver!
audio_jungle
Regular
Posts: 188
Joined: Sat Aug 04, 2018 9:20 pm

Re: Recording on Different Channels?

Postby audio_jungle » Mon Aug 13, 2018 3:29 am

CS70 wrote:If I have a choice between a physical audio interface and a virtual one, which should I choose for podcasting.

Not sure what you mean with "virtual audio interface" :), an interface is a physical object which connects devices on one side and computer on the other.
[/quote]

In the modern world, a lot of people do everything on their computer.

Rogue Amoeba's "Loopback" software appears to be a digital/virtual audio interface/mixer of sorts.


CS70 wrote:If you want to make a "radio show" mixing vocals, pre-recorded music and sound effects (not live) all you need is a microphone for each voice you want to record at the same time, and an interface which allows you to plug in the mics on one side, and get the signals on the computer on the other; and a DAW (digital audio workstation, on mac you have garageband I guess?).

But the problem is that the only audio source I would be capturing from a hardware device would be my own voice.

Music and sound effects would come from my macintosh.

A Guest would be calling me over VoIP and my Zoiper software phone would ring on my Macintosh and so I would be talking to that person (and recording him/her) all through software. (And that is much more complicated than you'd think!!)

Someday I might have a person physically sitting across from me at a desk, but that would be a less common thing.


CS70 wrote:If you want to do that live, you need pretty much the same setup, except is far easier to balance on the fly with real faders, so you need a real mixer or even better an interface/mixer. You can still use the DAW to record the mixer output (i.e. your programmer) or even the individual signals so that you can alter the balance later.

That is what I was asking before...

Just like using a trackpad can be a real pain in the ass, I am finding out that trying to SMOOTHLY grab a control in a software program and smoothly adjust it to create a fade is nearly impossible.

So I was wondering if there was some hardware device - maybe USB driven - which would have knobs and sliders that I could use to adjust software to create smooth fades?

Similar to how a mouse is easier to use than a trackpad for many. And why they now have writing pads where you can take a pen/stylus and simply draw things out similar to how you would on paper, versus using a shaky hand trying to guide your cursor along the way.

Follow me?
audio_jungle
Regular
Posts: 188
Joined: Sat Aug 04, 2018 9:20 pm

Re: Recording on Different Channels?

Postby audio_jungle » Mon Aug 13, 2018 3:37 am

@desmond,

The weekend is over and it's time for bed. :(

At least I was able to figure out how to set up an IVR this weekend using Zoiper!

Your detailed post about setting up Loopback is exactly what I need help with, but this thread is sort of morphing and I have lots of questions.

Can I create some new threads that are more specific, and we pick up from there?

It sounds like you are the right person to talk to getting help with all of this!!

Thanks,


Audio Jungle
audio_jungle
Regular
Posts: 188
Joined: Sat Aug 04, 2018 9:20 pm

Re: Recording on Different Channels?

Postby CS70 » Mon Aug 13, 2018 7:26 am

audio_jungle wrote:In the modern world, a lot of people do everything on their computer.

Rogue Amoeba's "Loopback" software appears to be a digital/virtual audio interface/mixer of sorts.


Lol yes, but you still need a physical interface at some point if you're going to use a physical signal source like a microphone. Even if you are using an USB one, the interface is simply built-in into the mic body itself. And you are gonna have a mic, ain't you? Then you need either an interface, or a USB mic (with its built-in interface)..

Of course, if all your sources are already inside the computer (say you want to jam with a synth application over music played by your computer music player), all you need is a software (virtual) signal router (like Loopback). But that's not the case for a podcast/radio show, where you need a mic. Not a big deal, but calling it "virtual interface" is a little misleading, few people would understand what you mean.

You can then take the signal channeled by the interface and route it into an input of the DAW. You will take the output of the music player and make it accessible to the DAW via the signal router. In the DAW, you can mix the two.


But the problem is that the only audio source I would be capturing from a hardware device would be my own voice.

Music and sound effects would come from my macintosh.

That is where it makes a difference if you are live or not. If you are not (all your sources are pre-recorded), you wouldn't need anything else that import your pre-recorded tracks in the DAW and balance.

If you are live, and want to mix external (say microphone) inputs with the signal produced by say a music player or Skype, one way of doing it is to use both a physical audio interface and a software router - both of them will produce signals that go in the DAW virtual mixer.

The reason for using a DAW also in this case is simply that they tend to be very well engineered beasts for which that task is trivial, and thus rock-solid, that they come with a wealth of effects and processing which can be useful also in a live setting (software reverbs and compressors for example) and you're likely to have one for free already. :-)

That is what I was asking before...

Just like using a trackpad can be a real pain in the ass, I am finding out that trying to SMOOTHLY grab a control in a software program and smoothly adjust it to create a fade is nearly impossible.

So I was wondering if there was some hardware device - maybe USB driven - which would have knobs and sliders that I could use to adjust software to create smooth fades?

Yes there are - depending on which precise setup you end up with, you may need different stuff.

The easiest is perhaps a control surface for the DAW - which control the software just like a mouse, but via faders, knobs etc:

- you set the gain of the mic on the interface (or on the onboard interface of the USB mic if you use one and it allows you, many don't but it's no big deal anyways)
- you set the level of the music/skype on the relative software, so that it's an a healthy level
- once set, you leave these unchanged
- you route the signals to the DAW and you make the balance there - using a control surface to control the individual faders in the DAW's mixer.

One final note: if you use Skype, your major issue is going to be quality of the signal, dropout and latency, which can make an otherwise interesting conversation really annoying to listen to. Unless you really really need to be live, my $.01 is that it'd be much better to first record the interview in its entirety (using loopback plus a DAW as a recorder): that produces you a audio file that you can improve, cut and polish at will.
Then you import your music (licensed, of course ;-)) into the DAW, and mix it just so.

That way - quality's gonna be far better and you don't have to worry about real time fades at all.
User avatar
CS70
Jedi Poster
Posts: 5274
Joined: Mon Nov 26, 2012 1:00 am
Location: Oslo, Norway
Silver Spoon - Check out our latest video and the FB page

Re: Recording on Different Channels?

Postby desmond » Mon Aug 13, 2018 8:37 am

audio_jungle wrote:To record my voice, I will use either the dynamic or condenser mic.

Ok, so your first source to add to Loopback will be a mono input from your physical audio interface that your mic is plugged into.

audio_jungle wrote:I expect to want to have background music and special effects, so I'll use VLC or iTunes for that.

If you want to add these in live to your recordings, then again, these should be stereo sources addd into Loopback so they get recorded. You can probably use the same pair of stereo channels in Loopback for these, but you can have an independant pair of channels for each playback source if you need to.

audio_jungle wrote:To interview people by phone, I will use Zoiper.
audio_jungle wrote:Everyone uses Skype, but that seems dirty to me as a Mac user.

So again, Zoiper will be another source added into Loopback, probably a mono channel. One thing to bear in mind is that you are recording the audio output of Zoiper, and if it's just one person it's not a problem, but if it's more than one, you don't have individual audio channels for each - you'll be recording the output of Zoiper which would be all callers mixed together (unless Zoiper has a way of directing individual callers to individual audio outputs (I'm not familiar with it).

Everyone uses Skype because it's the most common thing people have that (mostly) works. However, quality podcasts in general don't use *recordings* from Skype, then usually use double-ended recording, where the caller is recording his side of the conversation on his system, and sends you the files once the session is over. This means that your program remains high quality and is not affected by voip dropouts etc.

However, for callers that aren't able to do their own recording, then recording the voip output is more of a necessity.

(To be clear, you *do* want to record the voip output, as a reference and as a backup recording, but if your caller can record locally as well, and send you the files, you'll get a better quality program.)

The thing that will make things more complicated is if you need your caller to hear your other sound sources live (music piped in via iTunes etc) as in that case, rather than just getting the voip software to send your mic signal to the caller, you now have to send a composite signal, but without the voip audio as you don't want to get feedback etc. This makes routing a bit more complicated (though Loopback is your tool here - you'd simply create a second Loopback device with all sources except the voip signal, and use that as the voip's input instead of your mic.)

But if you can keep things simple (at least at first) it will, well, be simpler to deal with.

audio_jungle wrote:I would prefer to use Audacity in the beginning since it is free and I am familiar with it at least as far as basic editing of music I record.

Ok, so you'd select Loopback as your audio input device in Audacity, and record to multiple tracks as I showed in my Logic example above.
User avatar
desmond
Jedi Poster
Posts: 9559
Joined: Tue Jan 10, 2006 1:00 am
mu:zines | music magazine archive | difficultAudio

Re: Recording on Different Channels?

Postby desmond » Mon Aug 13, 2018 8:42 am

audio_jungle wrote:Just like using a trackpad can be a real pain in the ass, I am finding out that trying to SMOOTHLY grab a control in a software program and smoothly adjust it to create a fade is nearly impossible.

So I was wondering if there was some hardware device - maybe USB driven - which would have knobs and sliders that I could use to adjust software to create smooth fades?

You can't really do this with Audacity, it's too simple, but you could with a proper DAW like Logic/ProTool/etc and a control surface.

However, you shouldn't need to do this - once your rig is setup, you shouldn't need to do anything while recording except concentrate on your word/interviewee, and you capture to files, which you can mix after the recording, add fades, etc. You'd imply check your caller's level before you start, make sure it's loud enough, and then start recording...

If you really needed to do this, you could also get an audio interface with multiple inputs/outputs, send all your sources via Loopback out of your audio hardware on multiple channels, into an analog mixing desk, ride the levels there, and then back in to the computer but again, it's more complexity and you shouldn't really need to do any of that.

audio_jungle wrote:Can I create some new threads that are more specific, and we pick up from there?

If it's all the same topic, I'd prefer one thread to discuss this. When information is parcelled out across multiple threads, it makes it very hard to keep track and clutters up the forum for others.

If you have separate questions on other topics not related to setting up your podcast, then by all means create a new thread for those... thanks.
User avatar
desmond
Jedi Poster
Posts: 9559
Joined: Tue Jan 10, 2006 1:00 am
mu:zines | music magazine archive | difficultAudio

Re: Recording on Different Channels?

Postby ef37a » Mon Aug 13, 2018 8:57 am

I would like to pickup on one thing you wrote A.J? "Don't want to clutter up a new PC drive with odd downloads".

Sorry chap but you will HAVE to at some point if you are going to learn. I faced this problem years ago when I was even more of a PC numpty than I am now. I solved it by having a spare partition on my hard drive and used that for such programs. Once I had got to grips or decided they were not what I needed or thought I needed I could uninstall them but more importantly, periodically format the drive and re gain the space. I also suggest the use of Ccleaner to spruce the Registry and Revo Uninstaller.

I am not sure you can make a partition on an existing drive that holds your OS? If not I have found 500G 7,200rpm drives now cost less than 30 quid! Better would be an SSD but only if you intend to use it as the system drive in the future, otherwise a waste of money.

You might be able to use an external USB 3.0 drive for this purpose? As I say...Numpty!

And have you Googled for "Podcasting for Dummies"? Listen also to BBC R4 discussions for how to "set out" a stereo panorama. Archers?

Dave.
ef37a
Jedi Poster
Posts: 11490
Joined: Mon May 29, 2006 12:00 am
Location: northampton uk

Re: Recording on Different Channels?

Postby audio_jungle » Mon Aug 13, 2018 12:22 pm

desmond wrote:
audio_jungle wrote:Can I create some new threads that are more specific, and we pick up from there?

If it's all the same topic, I'd prefer one thread to discuss this. When information is parcelled out across multiple threads, it makes it very hard to keep track and clutters up the forum for others.

If you have separate questions on other topics not related to setting up your podcast, then by all means create a new thread for those... thanks.

This is an excellent thread, but it has mushroomed way too much for me to process all of these different topics at once.

I am going to step back and ask more precise questions on like the 100 topics above.

Hope the people in this current thread join in on my other questions.

Definitely lots of smart people here, but I think I need to rewind and do a deeper dive on each sub-topic.

Thanks!
audio_jungle
Regular
Posts: 188
Joined: Sat Aug 04, 2018 9:20 pm

Previous