How to render MIDI to wave in RealBand or PowerTracks Pro Audio

This tutorial covers the following topics:

• Overview
• Rendering MIDI to wave by recording in real time
• Direct Rendering MIDI to Wave using a DXi synth
• How to burn an audio CD

Last updated:  Wednesday, 31 August 2011

Overview

A MIDI performance can easily be converted to audio within RealBand or PowerTracks Pro Audio. This process is referred to as "rendering". There are several reasons why you might want to render MIDI tracks of a .SEQ or .MID file to digital audio. For example, you may want to add digital audio effects such as reverb, distortion or compression to your tracks, or you may want to convert your song to a compressed audio format such as MP3 or WMA. Another popular reason to render MIDI to wave is to create an audio CD, since MIDI files cannot be used to burn a CD.

This is normally a straight forward process; we have included a lot of detail in this tutorial because it is one of our most common technical support questions.

Before rendering your song to wave, you need to make all of the changes that you want to make to the MIDI data. Note pitches, durations, velocities, etc. cannot be edited once you have converted the track to digital audio. There are two different methods that you can use to render MIDI to wave:

1. You can record your MIDI tracks in real time. This method...
   
   • Is possible with any version of PowerTracks Pro Audio later than version 3.5.
   • Requires you to set your sound card's recording properties correctly.
   • Takes a relatively long time.
   • Allows you to convert a single MIDI track in a multi-track file to its own separate audio track.
   • Allows you to use any MIDI device, including an external synthesizer or sound module, as your sound source for the wave file.
2. You can use a DXi synth and "Direct Render" your songs to wave. This method...
   
   • Requires PowerTracks Pro Audio version 9 or higher.
   • Does not require you to set up any recording properties.
   • Is much quicker.
   • Allows you to convert a single MIDI track in a multi-track file to its own separate audio track (Version 10). Version 9 does not have this feature.
   • Requires you to use a DXi synth as your sound source for the wave file.

Rendering MIDI to wave by recording in realtime

1. Open the Record Control panel of your sound card mixer. In most cases you can open this from within RealBand or PowerTracks by opening the VU meters (Window | Show VU Meters), and clicking on the speaker icon between the Input and Output meters. **It is important that you select the correct recording input here, or else nothing will be recorded and you will end up with an empty .WAV track. This is the most common mistake made.** You will want to set the volume level of the selected input appropriately. As a general guide, try setting it to about 3/4 of the way up, and then adjust it appropriately if you get any clipping, or if you find that the volume is too low. If you have more than one sound card installed on your computer, make sure that the audio input driver you have selected is where you will be recording from. More information about selecting your recording device.
   You need to select one of the items in the Record Control:
   • If you are using your sound card's built-in MIDI synth as your MIDI output driver (Options | MIDI Devices), select "MIDI". If you don't see MIDI, look for Synth, Synthesizer, FM Synth, Stereo Mix, Stereo Out, Wave-Out, Mixed Output, or something similar. This varies between sound cards and computers. If you do not see any of those, go to Options | Properties. Below where it says "Show the Following Volume Controls", make sure one of the devices mentioned above is selected, then click [OK]. You should now see that device on the Record Control panel.
   • If you are using a software synthesizer such as the Roland VSC or Microsoft GS Wavetable as your MIDI output driver, select "WAVE". If you don't see WAVE, look for one of the other items listed above and select that.
   • If you are using an external MIDI module as your MIDI driver, you will need to use audio cables to connect it to a line-in on your sound card. You will then need to select the appropriate item in the Record Control panel - ie "Line-in".
2. If you had the metronome enabled, you will probably want to disable it for recording. You can do this in the Options | Metronome dialog.
3. Now you will record your MIDI tracks onto one or more audio tracks. If you want to record all of your MIDI tracks onto a single audio track, leave all of your MIDI tracks un-muted. If you want to record each MIDI track onto its own audio track, mute all MIDI tracks except for one of them. If you have other audio tracks in your song, you will want to mute those as well.
4. Select any blank track and change it to an audio type track. This is done by right-clicking on the track info field, pointing to Track Type, and selecting either 'Audio-Mono' or 'Audio-Stereo' (Version 9 or higher), or by double-clicking on the MIDI symbol under the Ty column to change it to a waveform symbol (Versions 8 and earlier). Whether you want a Stereo or ono Audio track is up to you. Press the Record button, and wait while your song plays through to the end. When it is finished, you will be asked if you want to keep the take. Answer "Yes".
5. Check to make sure that the recording process was successful: Play the track by itself by selecting the track and pressing the [S] button (solo). You should also be able to view the waveform of the digital audio track in the Track Overview panel (Version 9 and higher), and in the Audio Edit Window (Window | New | Audio Edit Window).
6. If you have opted to convert each MIDI track to an individual audio track, repeat steps 3 to 5 as many times as necessary to convert all your MIDI tracks to audio tracks.

Merging to stereo wave or compressed audio

You now have all of the tracks in your song in digital audio format, however your audio data is still part of your .SEQ file. You can merge your whole project to a stereo wave file, a compressed audio file such as an MP3, or a Windows Media Audio (WMA) file by going to the Audio menu (or the File | Wave Files menu in PowerTracks 11 and earlier), and choosing the appropriate menu item. Before you do this, make sure that none of your audio tracks are muted. If your goal is to burn a CD, merge your tracks to a stereo wave file. Note that if you choose to merge your tracks to a compressed format or .WMA, PowerTracks will first prompt you to save as a wave file. The File Converter dialog will be launched automatically after the wave file has been created. This is the same Windows dialog that launches from the Sound Recorder - File | Properties | Convert option. From this dialog, you can choose the type of compression that is appropriate (from the available drivers). You can save your settings as named presets by using the "Save As" button. For example, if you choose Microsoft ADPCM as the compression method, and choose 44K, you'll get a 4:1 compression and a bit rate of 43K / second. You can save this as a preset called "MS ADPCM44K" or whatever name you like. If you would like to save your rendered file as an MP3 file, you would choose "MPEG Layer-3" from the 'Format' pull-down menu.

Note: If you get a "Driver cannot do requested conversion" error when trying to encode an MP3 file, this suggests that your computer does not have an ACM (Audio Compression Manager) compatible MP3 codec installed. PowerTracks uses the Windows Audio Compression Manager functions to compress files. The types of files and bitrates that PowerTracks can encode depends on the codecs you have installed on your computer. On Windows XP, you can check to see if you have an MP3 codec by going to Control Panel | Sounds and Audio Devices | Hardware | Audio Codecs (Properties) | Properties. On Windows Vista, try going to Help | About | Technical Support Information in Windows Media Player. Look to see if there is an "MPEG Layer-3" codec listed there. Also (on Windows XP), select it, click on Properties, and check to see that it isn't a "decode-only" codec. If you don't see an MP3 codec there, or if it is a decode-only codec, PowerTracks won't be able to encode MP3s.

To solve the problem: Due to licensing restrictions and patents on MP3 technology, we can't include MP3 codecs with our software. There are a couple possible solutions - (1) The latest version of Windows Media Player includes an ACM-compatible MP3 codec, l3codecp.acm, which you should find in your Windows\System32 directory, and it can encode MP3's at high bitrates. This codec may or may not be enabled on your computer though. Or, (2) Search online for an MP3 codec that you can download and install. Or, (3) Save your file as a stereo wave file and do the conversion from wave to MP3 in a third party program.

Direct Rendering MIDI to wave using a DXi synth

If you are using a DXi synth for playback, rendering is much simpler and doesn't require you to do any recording.

1. You must have a DXi synth selected for playback, otherwise this will not work. Learn more about using a DXi synth for playback.
2. To merge all MIDI tracks *and* audio tracks in your song to a single stereo wave file, WMA file, or compressed audio file such as MP3, simply go to Audio | Merge Audio and DXi Tracks... (or if you you have PowerTracks 11 or earlier, go to File | Wave Files | Merge Audio and DXi tracks...). If your goal is to burn a CD, merge your tracks to a stereo wave file. Note that if you choose to merge your tracks to a compressed format or .WMA, PowerTracks will first prompt you to save as a wave file. The File Converter dialog will be launched automatically after the wave file has been created.

   If you get an error when you try to compress a file, see the note above about codecs.

If you have PowerTracks Pro Audio 10 or higher, you can also convert each MIDI track to an individual audio track (as long as the MIDI track is using a DXi synth). To do this, right-click in the Track Overview area of the Tracks Window, and select 'Auto Convert Individual MIDI track to audio track'.

How to burn an audio CD

You have now created your wave file and are ready to use that to burn a CD. Your computer needs to have a CD burner (most modern computers do), and you need to have a recordable CD (CD-R). You will also need to have a CD burning application installed on your computer. Most likely, your computer or CD burner came with one. There are a variety of third party CD burning applications available. We also include a simple CD burning application with PowerTracks Pro Audio (Versions 7 or higher) called MINIBurn. You can use this application if you want to do all of your work without leaving PowerTracks. However, if your CD drive isn't recognized by MINIBurn, or if you want to use some more advanced features not avaible in MINIBurn, you will need to use your third party CD burning software. Make sure it is set to create an audio CD, and consult the documentation for that software for further help.

You should download and install the latest update patch for your version of PowerTracks, as the update patches include MINIBurn updates and fixes: PowerTracks Pro Audio updates.

1. The first thing you should do is to test the wave file by playing it with a wave file player such as Windows Media Player. Otherwise you may end up wasting a CD-R.
2. If you want to use MINIBurn, in PowerTracks go to the Audio menu | Launch CD Burner (or with PowerTracks versions 11 and earlier, File | Wave files | Launch CD Burner). This will launch MINIBurn.
3. Go to the File menu, and select Add Track, or press the [ADD] button in older versions of MINIBurn. Locate your wave file and press Open. This will add the wave file to your "burn list". You can continue to add additional wave files to your burn list in this way.
4. After choosing your preferred settings in the MINIBurn window (check the MINIBurn help for a detailed explanation of these), click on the [Burn CD + Finalize] button. The end result will be a CD that you should be able to play in any CD player. We recommend that you don't use the [Burn CD - no finalize] feature (if you want to burn one song at a time), as this isn't compatible with some newer CD drives and may create a corrupt CD.

If MINIBurn reports that your CD burner is not compatible, or crashes when you try to open it, you should first install the latest update for your version of PowerTracks (PowerTracks Pro Audio updates). If that doesn't help, you will likely need to use a third party CD Burning application as discussed above.