Tech: Reviews


Unison technology allows the user to imprint the VOXBOX hardware preamp’s personality on an Apollo preamp.


Vocal Chain and Transient Shaping Processors

By Tim Douglas Dolbear

Universal Audio’s award-winning plug-in collection for the UAD platform is extensive and ever-growing. The company’s award-winning Apollo audio inter­faces work with many of their plug-ins and allow for real-time processing while recording and for the plug-in channel strips to control many different characteristics of the Apollo pre­amp. The two reviews here test something old (an accurate em­ulation of the Manley VOXBOX channel strip), and something new (the Sonnox Envolution transient shaper).


Universal Audio’s development of the Manley-sanctioned emulation for the UAD platform did not just set out to model the workings of the VOXBOX; it also incorporated Apollo’s Unison Technology, al­lowing re-creation of the hardware preamp’s characteristics while using the inputs and preamps on the Apollo hardware.

The UA VOXBOX contains all of the sections of the hardware unit, including the Optical compressor, De-esser (which can also be a secondary 10:1 limiter), and Pultec-style EQ. The optical com­pressor has the added benefit of a Link/Separate switch for working with a stereo signal during mixing. Another plug-in-only feature is the addition of a XFMR IN switch. On the hardware unit, the XLR output is fed from the output transformer while the ¼-inch line out is fed before the output transformer and thus does not have the associated “transformer” sound. The XFMR switch allows a user to access both output flavors achieved with the hardware unit.

For this review, Manley shipped me a VOXBOX for comparison. Although this was an early unit tested by UA, it was ultimately not the unit modeled for the plug-in. After the hardware had warmed up for more than an hour, I routed the hardware VOXBOX into channel 1’s line-in on the Apollo. This way, the analog circuitry in the Apollo and A/D conversion would be the same as when I plugged the microphone straight into channel 1 on the Apollo with the UAD VOXBOX plug-in loaded. For a fair comparison, I wanted to go through the same channel for the “B” test to remove any question that a change in the basic signal chain would have added any color to the sound. For the plug-in comparison, I unplugged the line-in from chan­nel 1 and plugged the mic into the Apollo’s Channel 1 Mic input, this time with the VOXBOX plug-in on the channel (the hardware unit was never plugged into the channel at the same time as the plug-in was ap­plied and compared.) I recorded the two setups to two separate channels taking care to match the levels then came back the next day to A/B com­pare with fresh ears.. All results were recorded at 96 kHz into a Magix Sequoia DAW. Listening back was done over multiple sessions using a Mytek Stereo192DSD into Neumann monitors. The Apollo’s pre­amps are professional-sounding—clean, clear and concise.

One of the truly stellar aspects of the hardware VOXBOX is its ability to draw sound from the microphone, pulling resolution and depth. When first recording acoustic guitar using an AT4050 in Omni, the Apollo sounded more upfront, tighter and modern, while the hardware VOXBOX had a more open top end with a three-dimensional depth and true-to-life sound. I got similar results with vocals and other acoustic instruments. One of the favored methods for tracking bass guitar is to go directly in using a hardware VOXBOX, and during testing this was the one example where I struggled to hear a difference between the hardware and Apollo.

The A/B tests were compared between two Se­quoia channels, one recorded line-in with the hard­ware VOXBOX, the other with the mic plugged into the mic input, where the VOXBOX plug-in was used (at no time was the plug-in and hardware used in a serial fashion). Because of the difference in sound at the input between the hardware and the plug-in versions, I was unable to find a perfect A/B test of the EQ section. Because of the difference in sound at the input between the hardware and the plug-in versions, I was unable to find a perfect A/B test of the EQ section. I can conclude that using the UA VOXBOX during mixdown was everything I hoped it would be. The reactions of the dynamic processors and sound of the expanded Pultec EQ are Manley VOXBOX all the way.

Does the UA VOXBOX replace having a microphone connected to an ac­tual Manley preamp? The answer would be no. It’s different; not bad, just different. You may think because the unit isn’t the actual hardware UA used, there could be a slight difference, but what I heard was not subtle. Knowing this, would I want a VOXBOX to use with my Apollo and/or during mixing? Definitely, if not just for the Dynamics and Pultec EQ alone. The emulation of the VOXBOX’s processors is top-shelf.


COMPANY: Universal Audio
PRODUCT: Manley VOXBOX Channel Strip
PRICES: $299
PROS: Excellent emulation of the Pultec EQ sound. Paired with Apollo for Unison Technology real-time tracking.
CONS: Preamp section is excellent but does not have the same flavor as the HW unit


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Envolution features separate transient and sustain sections and a broader Tilt mode.

In the late 1990s, SPL gave the audio engineers of the world the Transient Designer, allowing us to go beyond the dynamic audio shaping abilities com­pressors could achieve. At the time, it was hard to imagine describing the Transient Designer as limited in its ability. I still use my Transient Designer to shape drums. Now Sonnox has given us the Oxford Envolution based on the operational principles of a transient shaper, but with total control of the envelope and the ability to be frequency range-dependent.

The basics of the Sonnox Oxford Envolution starts with the same two controls we have grown to know and love: Attack (here called Transient) and Sustain. These control the level of boost or cut for the Tran­sient and Sustain sections and portions of the audio. The Transient section consists of a variable Attack time, Hold, Release time and a Sensitivity control, which controls how the plug-in detects transients.

The Sustain section has the same Attack, Hold and Release variable con­trols, and both sections contain the ever-so-important FREQ Button. If you click on FREQ in the Transient section, the center display changes to an EQ-style frequency display and the operator is given the ability to change the frequency range being addressed by the dynamic processor for the section. The available EQ types are a standard parametric style with bell shape or Tilt EQ, which also acts as a shelf EQ.

The output section offers three useful features beyond the simple output level fader. The Mix control is for parallel processing; the Warmth control adds harmonic content and gentle clipping on any peak overs on output; and a DIFF button allows you to hear only what is changed by the process.

Having the EQ filters is an amazing and powerful feature. On a simple snare drum track, where once we were only able to tighten up the snare or al­low its sustain to be brought out, now we can completely alter the timbre of the drum. On one mix, I completely changed out the snare from a bright and scooped sound to a fat, punchy sound by centering the transient boost around 200 Hz. Next, I boosted the sustain on just the high end to bring out only the snare wire sound without increasing the low ringing overtones of the drum.

On a bass guitar track that was suf­fering from fret buzz and clanking, I set the Transient section’s EQ for 1 kHz, and brought down the Transient control 12 dB and raised the hold time. This effec­tively damped the upper-mids and high end just on the part of the note contain­ing the offending buzz but left the sus­tain of the note’s full frequency. Adjust­ing the Sensitivity allowed me to hone in on only louder notes with the offending fret buzz, but did not steal the high-end fidelity from the rest of the track. The results from the Envolution were much more appealing than trying for the same fix using a Multiband EQ, as any loud sustaining note would trigger the multiband EQ. But on the Envolution, only the very beginning of the note would be darkened when triggered. The DIFF button came in handy in setting up this sort of dynamic EQ setting.

The Sonnox Oxford Envolution belongs in every audio engineer’s tool­box. I find new uses for it every day and am amazed at its ability to bring out, or clean out, audio content from a track.


COMPANY: Universal Audio/Sonnox
PRODUCT: Sonnox Oxford Envolution Plug-In
PRICES: $249
PROS: Frequency-dependent dynamic processing. Unique in its abilities.
CONS: None.


Five Processors Provide Automatic Spectral Shaping

By Barry Rudolph

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Neutron’s processors include an EQ, compressor, transient shaper, exciter and limiter.

Neutron is a music-mixing adjunct that combines iZotope’s latest audio processor modules, extensive metering and algorithmic analysis; it runs native in 32/64-bit AAX, AU, VST and RTAS hosts. Based on the engineer/producer’s predefined processing goals and stylistic pref­erences, Neutron will automatically develop and deploy custom­ized signal-processing chains and parameters as suggested starting points, using up to five of its Ozone-style processor modules.

Designed to process individual audio tracks from mono to eight channels wide, its top features are an algorithmic analyzer called Track Assistant and the Masking Meter, a clever real-time display of frequency collisions and buildups between any two tracks in your mix with the goal of remediation.

Neutron has three versions. Neutrino is a spectral shaping plug-in that subtly increases separation between instruments and is avail­able as a free download. It has four operating modes: Vocal/Dialog, Guitar/Related, Bass, and Drums/Percussive. It has controls for De­tail (its frequency range) and Amount (its dynamic processing depth). Neutrino is for smoothing out resonances and harshness, and it be­comes more effective when used on all tracks in a mix. Neutrino, as part of the Neutron plug-in, automatically selects one of those four modes in conjunction with every Track Assistant analysis.

The Standard and Advanced versions of Neutron are identical channel strips with both Input and Output sections, and five proces­sor modules: EQ, Compressor 1, Compressor 2, Exciter and Transient Shaper. The modules can be placed in any order by clicking and drag­ging, and are followed by Neutrino and the Limiter.

The limiter has three algorithms: Hard, IRC LL, and IRC II—bor­rowed from the company’s Ozone 7. There are also three modes: Mode 1 (Clear), Mode 2 (Smooth, a good starting place) and Mode 3 (Thick, useful for handling loud, low frequencies cleanly). Neutron Advanced supports up to 7.1-channel surround and includes separate plug-in versions of Neutron’s EQ, Compressor, Exciter and Transient Shaper modules that can be used anywhere in your mix.

I inserted Neutron Advanced on a lead vocal track and clicked on the Learn button. EQ Learn analyzes a short portion of audio wher­ever you start playback and places “nodes or points of interest” at response peaks caused by fundamentals, sibilance, rumble, P-pops and resonant buildups. For this vocal track, I played a section of a quieter verse going into a louder chorus section to get a representa­tive dynamic and spectral picture of the nature of the singer’s voice and the recording/production. I tried scanning other sections of the vocal track and essentially got the same results. I found EQ Learn an incredibly useful tool that’s better than a spectrum analyzer for identifying problems requiring corrective EQ.

The newly designed equalizer section has 12 adjustable bands with choices of vintage analog-style, Baxandall, band-shelf and pro­portional Q filters. In surround track instances of Neutron, there is an LFE bypass button so that the LFE channel passes through unpro­cessed and with the correct latency compensation.

I especially like that all these bands (except for the high and low filters) can be switched between static and dynamic modes with ad­justable threshold and a choice between compression and expansion. There are also side-chain facilities to control the dynamics of any EQ band from its own frequency, any of the other EQ bands in play, or from external sources using the plug-in’s side-chain input.

Next, I engaged Track Assistant on the same lead vocal track. The software’s learning algorithm first identifies the nature of the audio it is processing and selects one of the four Neutrino spectral shaping algorithms, or Clean where Neutrino is bypassed. Neutrino’s faders for Detail and Amount are set midway (50%) by default.

Track Assistant has a pull-down menu with three Modes that govern its strength: Subtle, Medium (default) or Aggressive. Three Presets further define the precise processing goals: Broadband Clar­ity (default), Warm and Open, and Upfront Midrange, for a total of nine combinations of Types and Presets to consider.

Running and constrained by the nine processing directives and Neutrino, Track Assistant scans audio and, in about 10 seconds, configures the signal chain order, parameters for all five of the mod­ules including any dynamic EQs. It also bypasses unused modules

 and sections to minimize CPU load. After a scan, a suggested chain position for the Transient Shaper is made (if deemed necessary) but not enabled, and the Limiter section must be manually turned on.

For my first scan, I set Track Assistant mode to Subtle with the Warm and Open preset. Neutrino switched to Vocals/Dialog mode and the equalizer had a 108Hz -12dB/octave highpass filter set, +3dB shelving boost at 247 Hz, a fairly high Q dynamic EQ cutting at 1095Hz, and +2dB of a proportional peak­ing EQ centered at 3,305 Hz. Compressor 1, a multi­band compressor module, was set to wideband with a ratio of 8:1, fairly fast attack and 1.2-second release times. The lead vocal sounded hardly processed at all, with original dynamics intact and a warm and fuzzy tone ready for my automated mix moves. This initial starting pre­set was very close to what I wanted, save for a few refining tweaks.

I next set the mode to Aggressive and used the Broadband Clarity preset and let Track Assistant rescan. Track Assistant applied corrective EQ set­tings at seven different frequencies, with two as dynamic EQs. Compressor 1 was set at a 10:1 ratio and multiband Compressor 2 had crossovers at 360 Hz and 3.27 kHz, again in Vintage modes. There are Digital and the new Vintage compression styles with RMS, Peak and True (Envelope) -level de­tection methods. iZotope’s 3-band Exciter module also came onboard with crossovers at 82 Hz and 3.25 kHz, with joysticks for each band to blend any mix of Warm, Tube, Retro and Tape harmonic profiles.

I would not have dreamt of using this kind of pro­cessing for a vocal track, but it sounded great, especially within the mix. Even with aggressive settings, the lead vocal never got harsh or angry sounding. I like that each of the five modules has Wet/Dry Global faders that are automatable, as are all the 200+ parameters in Neutron.

The Masking Meter shows auditory masking—the partial covering of one track’s sound by another playing at about the same time and in the same frequency range. The Masking Meter has two parts: ghostly white lights behind the frequency EQ curve (the brighter the light, the more collisions) and the Frequency Collision Histo­gram bar chart that tallies collisions over an adjustable, resettable, three-second window.

Masking, termed “loudness loss” of one track’s vol­ume while colliding, is measured relative to another track in your mix. Multiple tracks instantiated with Neutron show up in a drop-down window in each in­stance to compare them to the currently running track under scrutiny. You can name each instance with the track’s name, but I think iZotope should update the soft­ware so the track’s name automatically flows into each instance of Neutron.

On a pop ballad mix, kick drum and 5-string bass masked one another. I wanted good separation, though the kick was a big sounding 24-inch drum with a front head and the bass played the low B string throughout.

I started by running Track Assistant on both tracks. With kick drum set to Aggressive and Upfront Mid­range, all five modules came into play with the Tran­sient Shaper positioned right after the EQ but in bypass. On the bass track set to Medium and Broad­band Clarity, the Exciter module came up enabled right after the EQ. Later in the mix, adjusting the Ex­citer on bass gave it more presence, and I enabled the Transient Shaper on the kick to dial in more attack.

Clicking the Masking button on the kick drum’s Neutron instance and selecting the bass guitar track in the Masking drop-down window, the EQ window divided in half with the kick on top and the bass gui­tar EQ window on the bottom. I found this very help­ful visually when setting slightly different EQs between a kick drum and the bass. You can elect to use the Inverse Link mode to automatically boost on one track and cut on the other at the same time on the same EQ band.

I am impressed with Neutron Advanced’s automatic analysis and preset generation. I use Advanced experimentally and for problematic sources, and I love it! However, it’s not perfect—Neutrino mode had trouble identify­ing a drop-tuned stereo guitar track, causing Track Assistant to produce a thin-sounding preset. Using the Masking Meter information effectively is an acquired skill, and I find new uses all the time. Neutron is a powerful, advanced music mixing toolset that I’m thrilled to recommend.


Company: iZotope Inc.
Product: Neutron Advanced
Price: Neutron $249, Neutron Advanced $349
Pros: Remarkable mixing tool but not perfect.
Cons: Track name should show up in plug-in.


LF-Generating Plug-in Pushes the Boundaries of Bass

By Matt Zanardo

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Substance features a 4.75 GB library of sounds and 300 presets.

The Substance Bass Engine plug-in from Output is a modern and innovative instrument aimed at today’s boundary-pushing music makers. The interface is simple enough for new producers unfamiliar with synthesis to get a great sound right out the box, yet in-depth enough for experienced sound designers to sink their teeth into.

The sample-based instrument includes a 4.75GB library, 300 presets with smart-tagging, layered and global effects, a rhythm page that syncs to tempo, advanced arpeggiator and more. Substance runs in Kontakt or Free Kontakt Player version 5.5.1 or higher (Mac OS X 10.9, 10.10 or 10.11; Windows 7 or higher). My test system was running Ableton 9.6 on OS X 10.10.5 Macbook Pro Retina, mid-2012 gen.

After downloading Substance through Output’s trendy-looking App Hub, I imported it to my Kontakt player and immediately noticed that its signature interface sliders are just like its vocal engine Exhale. (Be prepared to activate Substance twice; once in the Output download Hub, and again in NI’s Service Center.) The sounds are immediately inspiring. After loading a preset and hearing the first note out of the monitors, I wanted to get working instantly.

The top-layer of the interface has six clear tab windows: Main, Edit, EQ, Filter, FX and Rhythm, with the preset list in the top center, macro and arp window tabs to its right, and four aux send sliders tucked in at the bottom. When clicking around, the interface responds smoothly, but it takes about three seconds to load a sound. Output recommends that users run a Kontakt Batch Resave to speed up the load time.

While it is described as a Bass Engine, some sounds in higher octaves could easily translate as a lead, or other “non-bass” sounds—especially after third-party processing.


The main Tab window contains four macro sliders, featuring a circu­lar layout split into three sections that combine to make your overall sound. Both macro sliders and individual sound categories change between each preset, showing off the depth of the Substance engine, giving you the ability to dive in and manipulate the core of each sound layer. Output excels at giving the user an easy way to interpret the oscil­lators of synthesis, but deliver it in a more musical, straightforward way. Under this main tab alone, you’re able to create an exciting sound to get you started. The preset menu allows the user to narrow down sounds by the character—dirty, aggressive, bass guitar, pad, and a lot more.

The Edit window is where you can go into your three sections and alter the sound character via sliders for attack, decay, sustain, and re­lease to achieve the desired effect. Also included are controls for pan­ning, tuning and sample start. For example, when using the sample start parameter with your attack, you can get the sound to articulate in a way that works with your compressor’s side-chain settings—essential when working with low end in electronic music.

The ability to not only play with the attack but also when the sample starts allows you to create a sound that can articu­late naturally and musically in your track. Under the Advanced tab, you can alter the glide, key range and velocity parameters. These are great for working with low end that needs to act as one coherent sound with the kick drum. For example, I like to commit my bass to audio and use simple fades to shape the sound with my kick along with side-chaining, rather than rely on the ADSR of the instrument .

The EQ window is unique and has a sound that matches the

 entire line of Output products. While this window assists in the design of a sound, I wouldn’t say it’s ca­pable of surgical EQ. Overall, the EQs are workable, but not a highlight feature for me, as the intuitive­ness and feel are slightly awkward.

The Filter tab is where it all happens. Within this tab alone you can easily get lost in the engine, trans­forming whatever you started with into something that isn’t even noticeably similar. Along with tradi­tional lowpass and highpass filters, it features reso­nant filters and a formant and phaser shape. ADSR capabilities can be bypassed entirely, per layer.

Finally, it comes fitted with a global filter at the bottom of the interface, limited to either a highpass or lowpass, allowing you to duplicate a Substance instance and treat your sub and mid-bass inde­pendently within the Filter window. Great job here by Output.


Substance comes with most of your standard effects, such as distortion, compression, delay and reverb, with a Motion tab (containing flanger, phaser and chorus) and Pitch. While the effects are effective, I like to save a lot of these to be handled by third-party plug-ins built specifically for the purpose. The sonic character of the effects is not impressive, but it is great that they are specific to each layer of the sound rather than processing the sound as a whole later.

In the Modulation tab, you can create and al­ter the movement of each layer respectively, or the sound as a whole. Each layer has volume, bite, cutoff and resonant parameters that act as a mac­ro linked to the parameters in the other Tab win­dows. For instance, the “bite” LFO links to the amount of distortion set by the bite percentage in the FX window, and the cutoff and resonant links to the Filter window.

This window is clearly a vital component to Sub­stance and holds a ton of happy accidents waiting to happen. The 16-step sequencer and flux tab are filled with standard and unique LFP shapes linked to timing and swing op­tions, with the flux option offering the ability to change the rhythm rate of modulation based on the flux step pattern

It’s safe to say the hype around Output’s Substance is justified. Filled with a massive 4.75GB library, it comes with a ton of unique and modern sounds and presets perfect for todays producer, plus more than enough internal ca­pability to modify the sound in-depth. Output is becoming a staple in mod­ern virtual instruments, and I love what the company has done. It will join Exhale as one of my go-to synths for all things low-end—and more.


To create a tight 808-style kick drum using Substance, find a sub preset and tweak it to taste. Then, instead of side-chaining it to your kick drum, “Commit” (Pro Tools) or “Flatten” (Ableton) the instance of Substance to audio as if it is a “one-shot” sub sam­ple. Next, find a short, punchy kick that you want to use for your attack/punch, and on the same channel,

grab the kick punch and overlap it with the sub audio sample. Last, crossfade the short tail of the punchy kick with the start of your subbass. By crossfading your kick punch with your sub rather then side-chaining it, you can create a tight punch to sub-bass ratio that sounds much like a long 808 kick drum.


PRODUCT: Substance Bass Engine
PRICE: $199
PROS: Simple yet powerful, modern and big. Fully capable of all things low-end. Signature to Outputs unique interface design style.
CONS: Sample-based, so 4.75 GB library can take some time to load.