How To Use IDAM With Digital Performer - Use iPad As Synth

[Babz]

As some of you may know, I've been making tracks in DP for the last couple of years using my iPad as an external instrument. There are many excellent apps out there nowadays, most of them 10 times less expensive than desktop VIs.

Since Apple implemented IDAM (Inter Device Audio MIDI) some time back, (as of iOS 11 and El Capitan, I think), you can now send MIDI and audio within your DAW using your standard Apple charging cable. I decided to create step by step instructions, if anyone needs them. You need a fairly recently iPad to get good results. Currently I use an iPad Air 1 w/ iOS 12.1 and DP 9.52.


How To Use IDAM With Digital Performer


1. Plug in your iPad to your computer using your standard Lightning-USB charging cable.
2. On your Mac: Go to Audio MIDI Set Up
3. Go to Window->Show iOS Browser. You should see your iPad in the window. Click Enable.
4. Launch Digital Performer and create a new Project.
5. In DP, go to Set Up->Configure Audio System->Configure Hardware Driver. You should see “iPad (input) in the list. If you are using an audio interface it should also appear in the list. Command-Click so that both are selected. Keep your audio interface the Master Device. Click OK.
6. In DP, create a MIDI track. Assign its output to Unconfigured Ports->iPad->iPad-1.
7. On your iPad, launch a synth app. Depending on the app, it may require that you enable external MIDI within its Settings. You should now have MIDI going to the iPad instrument.
8. To monitor, in DP create an Aux Track and assign its input to New Stereo Bundle->iPad (input): iPad 1-2. Play some notes on your keyboard. You should now hear your iPad synth. You can now record and play back MIDI in DP using your iPad and an external synth.
9. To record your MIDI track to audio, create a Stereo Audio Track and assign its input to iPad 1-2.
10. Record enable your audio track. Deselect Record Enable on your MIDI track. Hit Record.

**NOTE: Be sure to quit DP before disconnecting your iPad, otherwise it will give you a missing hardware error message.

Enjoy!

Babz
(AKA Lady App-titude)
You can check out some of the music l’ve created using DP and iPad apps here:
https://soundcloud.com/lady-app-titude

[Babz]

Another option is to use the inexpensive third-party app, Studiomux. It takes a different approach, using a plugin that you load into a DP instrument track, instead of the iPad as a hardware driver as in IDAM. Before IDAM, Studiomux was the main solution for using an iPad in your DAW, and it still offers certain advantages, including a different workflow, more complex routing options, and the ability to unplug or reboot your iPad without DP freaking out that there is a hardware driver missing. I still tend to use Studiomux more than IDAM.

One disadvantage to Studiomux is poor documentation. It works differently depending on the DAW you use, and the instructions offer zero guidance for DP users. I had to sort out things on my own using Logic instructions as an analogy. The good news is, I've done all the homework for you! To save you that trouble, here are my step-by-step instructions for using Studiomux with DP:

HOW TO USE STUDIOMUX WITH DIGITAL PERFORMER


1. Download the Studiomux app on your iPad.

2. Download and install the Studiomux server app from midimux.com.
Studiomux will appear in your Mac OS X menu bar. It is a very simple app that just shows the number of MIDI and audio connections. It will continue to always run, unless you choose Quit from its menu.

3. Launch the Studiomux app on your iPad

4. Tap the “+” (add Plugin) at the top of the app.
A list of IAA apps will appear at the left.
Choose one and drag it into the upper portion of a channel. This should automatically launch the IAA app.

5. Open a new Digital Performer project on your computer.

6. Create a MIDI track and assign its output to studiomux @ YourName's iPad-1*.
You should now have MIDI communication to the iPad. If you play, you should hear audio coming out of the iPad's speaker.

[*If your instrument is AU, assign the MIDI track output to studiomux generator-1]


7. For audio, create an Instrument track and assign it to zerodebug->studiomux generator-1.
The Studiomux plugin window should appear saying:
"receiving from YourName's iPad" with the name of the iPad IAA instrument that you loaded in the iOS appearing below. If it's says "None", click there and then select your app in the list.
You should now have audio coming from the iPad into Digital Performer and you should now be able to record MIDI notes in DP and have them playback just like any external hardware synth.

7a.IMPORTANT EXTRA STEP AS OF DP 9.13: From the studiomux generator-1 open window, you must choose “Run Open instances of this Plug-in in Real Time” from the mini menu own the upper right-hand corner. If you don’t do this, you will experience severe latency, because this window must always remain open.
Note: Sometimes I have found it necessary to unplug and replug the Lightning USB connection from the computer to get the DAW to see it.


8. RENDERING YOUR TRACK AS AUDIO.
To render your MIDI track as audio, you need to create and Aux track, assign it's output to a bus, and then create an audio track and assign its input to that bus. Here are the steps.

- Right-click (or control-click) on the output of your studiomux generator-1 Instrument Track and choose "New Aux Track Via New Stereo Bundle" and choose Bus 1-2 (or some other bus, if you prefer).

- Create a new Stereo Audio Track and assign its input to Bus 1-2 (or whatever bus you chose).

- Record Enable the Stereo Audio Track (and make sure you have deselected record for your MIDI track). Hit record. Your Studiomux MIDI track will be recorded into an Audio track.

That's It! Enjoy Studiomux in Digital Performer!

Written Nov. 2016 using DP 9 and Studiomux v 3.0.


Babz
(AKA Lady App-titude)
You can check out some of the music l’ve created using DP and iPad apps here: https://soundcloud.com/lady-app-titude

[bayswater]

This is great stuff. Thanks.

Does Studiomux deal with latency effectively?

[stubbsonic]

I'll mention Music IO by Power Trio (which was a collaborative effort from Confusion, Audeonic, and Secret Base-- all solid developers). Unfortunately, recent reviews suggest it might require a maintenance update. I wouldn't recommend buying it until they fix it.

[Babz]

This is great stuff. Thanks.

Does Studiomux deal with latency effectively?

Short answer: To the extent that latency has been an issue, Studiomux seems to be the better option. (One of the reasons why I still prefer it over IDAM.)

Longer answer: In general, latency is not an issue. However, I have found this problem which I call "creeping latency" (increased latency over time). That is to say, you start off fine, but after an hour or so, you start noticing lag, and after two hours or more, it becomes really bad. Also, walking away and letting things go into sleep mode may cause the problem too. The problem is remedied by rebooting the iPad. In my tests in the past, on long, all-day sessions, the issue occurred with both IDAM and Studiomux, but it seemed to take longer before it started to creep up w/ Studiomux.

I am still on El Capitan, and I've heard from some users that this issue was solved as of High Sierra. (But then other High Sierra users have posted that they have still had the problem.) I would love to hear from anyone else -- especially DP users -- about this issue. I kinda wish I had updated to High Sierra when I had the chance, but now it's all about Mojave and I'm not ready for that yet.

Then there is the iOS side of the coin. I'm still new in my testing with the latest iOS (12.1) and IDAM so I can't say for sure if the creeping latency is still there for me. (Maybe iOS 12 solved it? All I know is it was there for me in iOS 11 + El Cap.) What I can say right now is that if you can get your track recorded to MIDI relatively quickly, like in an hour or two, latency is not an issue. And if it does become an issue, rebooting gets you back to snappy.

Beyond that, things can vary depending on the iOS app. Many, if not most, of them have a buffer setting, and in general 256 is fine for me. But I can go as low as 128, and that can be even snappier. To go below 128, you need a more powerful iPad than my Air 1. (Mind you, these are buffer settings on the iPad, inside the iPad app. Buffer settings in DP make no difference, because the iPad is essentially a hardware synth module.)

More powerful iPad=better performance, more polyphony, more power at lower buffers, etc. But I still get excellent results even with an iPad Air 1. For example, the 2 GB Ivory Grand Piano runs fine and seems to get at least 100 voices or more of polyphony. The excellent Neo Soul Keys Studio (Rhodes, etc; 4 GB app) is fine on my iPad too.

You got all that? I welcome any discussion on this topic!

[Babz]

I'll mention Music IO by Power Trio (which was a collaborative effort from Confusion, Audeonic, and Secret Base-- all solid developers). Unfortunately, recent reviews suggest it might require a maintenance update. I wouldn't recommend buying it until they fix it.

MusicIO was the best, my favorite for a long time. The documentation and workflow are more straightforward compared to Studiomux. I had a great relationship with the developers and worked extensively with them, beta testing, etc., with great communication and fast bug fixes.

Then in late 2016 I developed audio glitches and dropouts with Music IO. (MIDI was still fine.) But they stopped replying to my emails, and AFAIK, they have not updated the app since 2016. I was forced to buy and learn Studiomux, and I basically consider MusicIO abandonware at this point. (Would love to hear otherwise, tho! )

[bayswater]

You got all that? I welcome any discussion on this topic!

I think so. I'll have to do some more reading. From the little I've seen before this thread, I thought IDAM was a iOS feature, and because of that, it would use some method of syncing to mac OS, so latency would not be an issue at all. That studiomux is perhaps better is not what I'd have expected. Either way, it looks like you've found that latency is not a practical problem in normal use. Might be a problem for live performance.

[Babz]

You got all that? I welcome any discussion on this topic!

I think so. I'll have to do some more reading. From the little I've seen before this thread, I thought IDAM was a iOS feature, and because of that, it would use some method of syncing to mac OS, so latency would not be an issue at all. That studiomux is perhaps better is not what I'd have expected. Either way, it looks like you've found that latency is not a practical problem in normal use. Might be a problem for live performance.

It’s built in to both MacOS and iOS, and requires a relatively recent version of both (I believe it’s El Cap and iOS 11 or higher). Also, changes, updates to either OS can affect performance. I have the latest iOS, but not the latest MacOS, and only just started testing with iOS 12. So I don’t know if creeping latency will still be an issue for me, or if it is an issue for others.

Back when iOS 11 and Sierra were the latest, one user I know reported that Apple did some optimization to MIDI in High Sierra and that he believes that’s why creeping latency went away for him when he updated from Sierra to High Sierra. Unfortunately, I never got a chance to confirm this myself. Thus, I would love to hear any reports on IDAM from anyone using High Sierra or other more recent OS.

Meanwhile, here is a demo video I found using Logic. It’s a little different in DP, but same basic concept.

https://youtube.com/watch?v=FmEJY8tY8vc

[bayswater]

Back when iOS 11 and Sierra were the latest, one user I know reported that Apple did some optimization to MIDI in High Sierra and that he believes that’s why creeping latency went away for him when he updated from Sierra to High Sierra. Unfortunately, I never got a chance to confirm this myself. Thus, I would love to hear any reports on IDAM from anyone using High Sierra or other more recent OS. I've got High Sierra and iOS 12.1; I'll try it when I get a chance.

[Babz]

I did some testing over two days, two different sessions, but results are inconclusive.

The first day I tested with a piano in Korg Module and after a couple of hours it definitely seemed like latency was increasing, and I rebooted DP and the iPad and it seemed to get better.

The next day, I tested with the freeware app Yamaha Synth Book (which is includes an excellent emulation of the Yamaha AN1x synth, BTW). But after 3 hours, there may have been a tiny increase in latency, but I can't say for sure.

It may be that the creeping latency issue may vary depending on the iPad app involved.

I wish there were some kind of software I could use to get an objective measure, so I'm not just relying on my sense of "feel".

Is there some free utility or some method I can use to test the latency of and external hardware device in DP? I need to measure the delay between when I press a note and when it sounds.

The hardest part about doing this test is the you really need to just leave the iPad plugged in for several hours for the problem to manifest, and every time I take break from a music session, the first thing I want to do is go surf the Internet on my iPad!

[Babz]

OK, here is what today’s test showed.


Problem: Switching apps on the iPad can cause latency under IDAM.

I first noticed this when running the Galileo Organ app. I always start off with a fresh boot of the iPad and no other app running except the instrument I want to play. Within the Galileo Organ app, I clicked on the “Help” option, which caused Safari to launch and go to a PDF.

When I went back to Galileo Organ, there was definitely severe latency. It is as if the interruption of the MIDI/Audio stream introduces buffer latency when the connection is restored.

When this happens, the only way to get things back to snappy is to reboot DP. (Closing the project isn’t enough. You have to quit and relaunch DP.)

I then rebooted everything (iPad and Mac) did some tests switching between apps on the iPad. This time I launched Galileo Organ and it was nice and snappy. I quit the app and switched to Korg Module, and it was fine. But when I quit Module and switched back to Galileo Organ, severe latency. Again, rebooting DP fixes it.

So it seems that under IDAM, latency can develop when you switch to other apps. It may be that this only affects certain apps. This would also explain the “creeping” nature of the latency. It may not be that it creeps up over time. But rather than during long sessions something happens to interrupt the connection (iPad going into sleep mode, for example) and when you resume, there is latency.

I’ve not had these problems switching apps with Studiomux, so I think I’m going to avoid IDAM and go back to Studiomux, at least for now.

Still would like to find some way to objectively test this latency. Anybody know of a utility or method for measuring playing latency of a connected external MIDI synth?