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Mixbus7-Final Showing recordings

Extract MIDI Audio and Notes in Harrison Mixbus 7

Have you ever wanted to output a MIDI file’s audio and also capture the actual MIDI notes that produced the audio into isolated tracks? A practical usage for this process is extracting the MIDI from a file where there are multiple instruments in the file, such as a drum kit’s kick, snare, toms and cymbals. With the extracted MIDI, you can have the source data available on independent tracks to help you create new instrument parts, variations or other embellishments without the need to endlessly copy, paste and manually delete instrument parts you don’t need. Follow the steps in this post to learn how to extract MIDI audio and notes in Harrison Mixbus 7.

14 December 2021 – Posted by Mike M.

Skill Level: Advanced

Tags: #mykmyrs #mikem #myersmediaplace #harrison #mixbus7 #daw #midi #drums #drumkit #polysher #configuration #audio #output #usbaudiointerface #usb #vst #mtpowerdrumkit

Why Do You Want to Extract the MIDI Notes????!!!!

That is the question I have received numerous times on various Internet forums and other groups while I was trying to figure out how to extract MIDI notes to their own isolated tracks. I’d also get suggestions like “Just record the audio output and be happy with that” or “Nobody needs to capture the MIDI notes while they’re playing” or “Just copy the whole MIDI file to a new track, highlight the notes you don’t want, and delete them”. Fortunately for me, I got more motivated to find the solution, and I did it with some free VSTs and a video tutorial on YouTube by Bill Edstrom. I originally wrote this post with instructions for Tracktion Waveform 11 Pro, but now that I am using Harrison Mixbus 7 regularly, I wanted to test if I could produce the same results – and I did.

First, Let Me Explain…

To step back a moment, here’s my motivation to extract MIDI audio and notes in Mixbus 7. I made a Mixbus project that uses a source MIDI file for performance by a VST drum kit instrument. The VST drum instrument, MT Power Drum Kit 2.0, plays the MIDI file and sends each individual instrument’s audio to its own track so that I can record the drum kit pieces’ audio on distinctly separated tracks (kick drum has its own track, the snare has its own track, etc.). I assume you do something similar to control the output levels of each of your kit’s pieces. If you aren’t separating out your kit components into dedicated tracks in your DAW, you may want to look into that practice sooner than later, especially if someone else mixes your work.

After a few sessions of recording audio tracks from the MIDI file, I realized that I may want to output the source MIDI notes in addition to the output of the audio. For example, having the kick drum’s audio and source MIDI notes allows me to save small, defined pieces of performances that can easily be copied, re-used or altered easily. If I decide that I am not liking a certain VST’s audio output, I can easily swap the VST drum instrument and re-record from my source MIDI. If I didn’t have the MIDI notes, I would potentially have to chop the audio file and edit it to create variations which could take a lot of time and effort.

But right now, I know you are still asking yourself why I would want to do this. Couldn’t I “just copy the MIDI from the main source track, delete out the instruments I don’t want and continue along my way”? Sure, but that could potentially be a lot of work and re-work if I make one or more errors in my edits/copy-paste.

For my workflow and the way I work, I tend to write my drum parts and guitar riffs in very small sections, generally 1 or 2 bars at a time. When I write in small sections, I can audition the audio and the MIDI to tracks to do A/B comparisons easily. I can edit the captured MIDI and play it back in small sections to create variations and copy them back up to my main source MIDI track as I build the overall song. The best part is that I am using technology to do the repetitive grunt work of capturing audio and MIDI notes with simply arming tracks for record and doing a take.

What You Need To Succeed

Make sure you install all of the prerequisite plug-ins before attempting to continue. Linux folks, I apologize but the eaReckon MIDIPolysher is only available for Mac and Windows, so if you can find a MIDI filtering tool for Linux, you may be able to substitute it for MIDIPolysher.

This lesson is the just the starting point of the series and shows how to use one drum kit plug-in to capture individual drum kit pieces’ MIDI source to extract MIDI audio and notes in Harrison Mixbus 7.

I originally wrote this post using Tracktion Waveform 11 Pro, and you can read that one here. I will say that Waveform uses the concept of track folders for organization, and I really miss that in Mixbus 7 to keep the track clutter at bay.

Steps to Extract MIDI Audio and Notes in Harrison Mixbus 7

  1. These steps that follow are for the kick drum only. You’ll need to repeat these steps for each kit piece in your drum plug-in. It’s a fair warning that it will take quite some time to map out the tracks for all the pieces your kit uses.
  2. Create a new Mixbus 7 empty session.
  3. Create a new MIDI track and name it “MIDI Source”. This track will hold our drum pattern file(s) and represent our entire drum parts for a track. Mixbus7-Create MIDI Source
  4. Place a MIDI file on the MIDI Source track. For this tutorial, use any drum MIDI you want, just be sure it has multiple instrument parts like kick, snare, cymbals and toms so that we can separate them into their own source tracks. Make sure you click the General MIDI Synth plug-in on the left-hand side and deactivate it because we do not need its services for our MIDI purposes.Mixbus7-Add MIDI File
  5. Create a new MIDI track and name it “Kick MIDI Filter”. This track will be used to receive the MIDI from the MIDI Source track and perform a filter with the MIDIPolysher plugin so that we only receive the kick drum’s MIDI information from the source file. Add the eaReckon MIDIPolysher plugin to this track. When propmted about replacing the General MIDI instrument on the track with MIDIPolysher, click REPLACE.Mixbus7-Add MIDI Filter Track
  6. The kick drum is MIDI note number 36 in the standard mapping for drums. We will use MIDIPolysher to only allow note 36 to pass through. Open MIDIPolysher and set the two key range values to 36, which is the kick drum’s MIDI note value. Note how all of the piano keys will turn red except for 36. Close MIDIPolysher after the configuration change is completed.MIDI Polysher Kick Drum Filter
  7. It’s time to do some input and output configuration now that we have our tracks in place. Select the Kick MIDI Filter track and go to its Routing Grid. In the Mixbus Tracks section, click the MIDI Source Out item to set its output as the input to Kick MIDI filter. Mixbus7-MIDI Filter Input Source
  8. Now let’s wire up the MIDIPolysher plug-in so that the MIDI coming from the MIDI Source track can be passed into the MIDIPolysher plug-in. Right-click the MIDIPolysher plug-in and choose “Pin Connections”. When the dialog window appears, connect the red input to Instance #1 so that it appears as shown. You may be able to notice that the Kick MIDI Filter track is showing an orange vertical bar on its signal meter, indicating that MIDI signal is coming into the track during playback. Mixbus7-MIDIPolysher Pin Connections
  9. Now that we have a track that is filtering the MIDI source data to only handle the kick drum, let’s make a new MIDI track to “print” the kick drum’s MIDI source notes. To save the notes, we simply arm the new track for recording and it saves the notes to the track. Make a new track and name the new track “Kick Only MIDI”. Mixbus7-Add Kick MIDI Notes Track
  10. On the new track, we’re going to add our drum VST instrument so that the MIDI the track receives can be printed. It will also produce the audio output of the filtered kick drum so that we can make a new audio track to capture (“print”) the audio output. Add MT Power Drumkit as a plug-in to the “Kick Only MIDI” track. Be sure to open the drum kit and click the “Skip” button so that the plug-in makes audio output if you haven’t donated to get a licensed copy.
  11. As with previous steps, we have to configure some input and output settings so that the filtered MIDI flows to the new track and the new track’s drum plug-in only plays the kick drum as we expect. Go to the Routing Grid for Kick Only MIDI and set the Kick MIDI Filter as its input source. At this point if you hit Play on the transport, your MIDI should be playing back only as the kick drum.Mixbus7-Kick Only Input Source
  12. Now we’ll add the final track to the group. Add an audio track and name the track “Kick Only Audio”. Mixbus7-Add Kick Only Audio Track
  13. As we’ve done previously, we need to set the input of the new track to the output of the prior track. Open the Routing Grid for the Kick Only Audio track and set as shown. Mixbus7-Add Kick Only Audio Input Source
  14. You can arm the Kick Only Audio track for recording and it will record only the audio produced by the kick drum’s MIDI source.
  15. Here’s a view of the MIDI source of the kick drum that was recorded on the Kick Only MIDI track, along with the kick drum audio that was recorded on the Kick Only Audio track. Mixbus7-Final Showing recordings
  16. At this point, you can repeat the steps and make a group for each of the instruments in your drum kit. Be sure to change the MIDI note value in the Polysher plug-in within each group so that you are filtering for the correct instrument.


We’ve finally reached the end of this tutorial. You now know how to extract MIDI notes and audio in Harrison Mixbus 7. While it was a long journey, you can save your project so that the configuration is finished and ready for your next project.

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