Nugen Audio cleverly added a downmix section to their excellent Halo Upmix plug-in so you could compare the downmix of the upmix with the original to make sure the upmix would downmix OK. Now they have taken that downmix feature and made it into a very powerful new take on a downmix plug-in.
Halo Downmix has been designed by the team at Nugen Audio for downmixing feature-film or 5.1 mixes to stereo, with controls for relative levels, timing, and direct vs. ambient sound balance allow fine-tuning, delivering downmixes that are no longer limited by typical in-the-box coefficients-based processes. We have an exclusive review of this brand new take on a downmix plug-in.
Nugen Audio Halo Downmix Features
7.1 and 5.1 modes
Advance and compact modes
Quick select 'in-place' monitoring of stereo and surround
Quick linked solo and mute at every stage
Ambient vs direct sound balance
Automatic rear channel delay detection
Surround input width control
Rear channel shelf filters
Downmix Low-Frequency handling
Highly customisable interface
Full input and output level metering
Direct numerical entry of all gain offsets
Adjustable meter colour splits
Surround energy distribution visualisation
Fixing Legacy Upmixing
A standard downmix is usually generated by simply mixing together the surround output according to standard downmix coefficients, however, this can often lead to unsatisfactory results, particularly if legacy upmix tools have been used to generate the original surround mix by controlling excessive diffuse sound from added artificial reverberation, or removal of delay artefacts introduced in the rear channels. Typical applications include:
• Stereo Mix production for Television within a Surround workflow.
• Rapidly producing a controlled, precise stereo downmix of a 7.1 feature film.
• Generating a stereo mix from surround where no stereo recording exists.
• Producing stereo interim listening mixes in a surround workflow.
Fine Tune Existing Surround material
Adjust existing 5.1 or 7.1 mixes in surround-to-surround mode. Individual channel levels and the balance of direct vs. diffuse sound can be adjusted to fine tune or re-balance existing surround audio where access to the original mix is not possible.
Parallel Surround/Stereo Downmix workflow
Halo Downmix can also be used in conjunction with the included Receive plug-in to enable a parallel surround/stereo workflow. Applications include:
• Optimising a surround mix for better stereo downmix (standard coefficients)
• Harmonising surround and stereo experiences, delivering a separate downmix
• Harmonising surround and stereo to produce a modified surround mix and stereo downmix
Halo Downmix System Requirements
Available formats - Halo Downmix is available as AAX, VST, VST3, AU and AudioSuite in both 64-bit and 32-bit versions.
Price: $199 until June 30th, 2017 and then the normal price will be $299.
Minimum System Specification
Mac OSX 10.7.x, 512 MB RAM
Windows XP or above, 512 MB RAM
Surround capable DAW/NLE.
Exclusive Review Of The Nugen Audio Halo Downmix Plug-in
In this video review, I explore the new downmix plugin from Nugen Audio, which is way more powerful than any conventional downmix plugin like the factory downmix plug-in included in Pro Tools. Halo Upmix users will find Halo Downmix somewhat familiar with a similar surround analysis display, but as with Halo Upmix, there is a lot more going on in this plugin.
Input Section
Starting on the left-hand side there is the input section with metering, channel labels, which double up as mute buttons and a phase reverse button for each channel.
Surround Control
The centre section is the Surround adjustment section with the Halo real time analysis, which can be colour coded, so you can see where the audio is coming from and the brighter the display the louder it is.
There are channel nodes, which double up as solo buttons and the stereo pairs are normally linked but you can break the link if you would prefer to solo individual channels.
On the front stereo channels, you can adjust the balance. On the rear channel, you can use HF shelving filter to cut or boost the high frequencies to help manage any imbalances in the surround channels.
Over on the other side, there is a rear channel delay option which can 'un-delay' the rear channels to sort out legacy upmixes that might have been done using an upmixing plugin that added delay into the rear channels to increase the sense of space and then doesn't sound good when downmixed.
You can allow the LFE channel to be passed through or not. Normally the LFE channel is discarded for a standard TV downmix but where the LFE channel has been used as a sub channel you might want to consider bringing the LFE channel into play.
On the right-hand side is the surround output section and from here you can adjust the levels going into the downmix.
The stereo pairs are presented in mid/side, rather than Left/Right. When you break the link you can adjust the mid and side separately providing, even more, control to the signal being fed to the downmix.
Downmix Section
Finally we get to the Downmix section on the far right. There is stereo metering with further gain timing and Margin indicators. At the bottom there is a high-pass filter to roll off the low frequencies as well as a mono filter to bring the low frequencies into the centre if necessary, it the LF image width is too wide.
Monitoring Section
Finally over on the bottom left-hand side is the monitoring section and this functions differently depending on how you choose to use the Halo Downmix. You can use it on a surround track in surround to surround mode and then use it to tweak the surround balance or switch to the downmix and hear that through the same track.
When you use the surround to stereo mode, you can use a Halo Receive plug-in on a surround track and then when you switch to Surround in the monitoring section, the output is routed through to the surround track and when you select Downmix you hear the downmix through the stereo track making it so much easier to compare the sound of the downmix to the surround mix.
There is also an input/output option and when you are using the downmix monitor path, listening to the input routes the incoming audio through a conventional downmixer and then the output allows you to hear the downmix through the Halo plug-in so you can also compare the Halo downmix to a conventional downmix.
My Conclusions
I have to say I am amazed at all the different options that are included in the Nugen Audio Halo Downmix plugin. I never thought that you could have so many options and control over a downmix. Until now, a downmix has always been a downmix, but now with the Halo Downmix, you can really refine the downmix so you can deliver the best stereo compatible mix possible.
The GUI cleverly hides the power and versatility of this plugin and brings so much more to the downmix table. The mid/side feature is an interesting choice and will take some getting used to fro some people. Others may find that there isn’t sufficient gain on the LFE channel, preferring at least 6dB of gain available rather than just 3dB. That said, well done Nugen Audio for rethinking what can be done when downmixing a surround mix to a stereo mix.
Alan Sallabank's Conclusions
Alan Sallabank has also taken a look at Halo Downmix and for him the good points are flexible monitoring and safety/compatibility monitoring through the "Receive" plugin, as well as a reasonably clear display.
On the other hand, Alan feels that there is not enough input trim gain, particularly in the LFE. He is of the view that the LFE channel should be folded in at +6dB relative to left and right channels, due to the lineup spec of a Dolby theatre with the front speakers set to 85dB, and the LFE channel to 91dB.
The safety monitoring is destructive. If you choose to monitor the downmix through the receive plugin, it switches off the downmix output.
Finally Alan asks why the stereo metering - L/R, Lss/Rss & Lsr/Rsr, are in the MS format as he finds it distracting.