Ntonyx Style Enhancer

This is the result of transforming a lead guitar solo supplied by Ntonyx using the 'Guitar Overdriven 110S 06A Solo Intensive Vibrato and Bending' style. A few of the notes had their lengths altered, but the majority of enhancement is MIDI controller data. The massaged velocity values are shown in cyan, added pitch‑bend data in purple, and modulation in red.

Martin Walker looks at a new stand‑alone utility that claims to add the human touch to MIDI data, and finds that it scores highly.

Compared to the output of a MIDI guitar or breath controller, keyboards can be very limited when it comes to expression. Although some keyboard players are prepared to perfect the skills of using pitch‑bend, modulation, aftertouch, footpedals, ribbon controllers and so on, it can still be difficult to make 'acoustic' MIDI instruments sound like the real thing without a lot of effort. In many cases the only solution is to draw in controller information by hand in the sequencer afterwards.

However, help may be at hand. Ntonyx's Style Enhancer Micro 2.1 is a stand‑alone playback application for Standard MIDI files that claims to add realistic human expression to a wide range of acoustic sounds. You import a Standard MIDI file, select a suitable style, such as 'Guitar Jazz 01A Solo Lyrical Simple and Chords', or 'Violin 01A Solo and Chords Traditional Simple', press the OK button, and then sit back to listen to how a professional guitarist or string player would interpret your score. And before you check the front cover, no, this is not the April issue: Style Enhancer 2.1 is a serious and potentially essential utility for MIDI musicians.

A Question Of Style

This small window is the nerve centre of the entire style‑enhancement process, and provides a wide range of customisation options (see main text).

Although there is now a huge range of audio effects plug‑ins for MIDI + Audio sequencers, MIDI manipulation facilities have traditionally been quite basic by comparison. Most sequencers offer event filtering, transposition, velocity‑shifting, and of course a comprehensive range of quantise options, but apart from various echo effects the creative possibilities have been quite limited. Ntonyx, a Russian company, were among the first to take advantage of the MIDI plug‑in architecture available in Cakewalk's Pro Audio 8 (see box) when they introduced a couple of plug‑ins offering 'style enhancement', but of course these are only useful to Cakewalk users.

Their latest product, Style Enhancer 2.1, is a stand‑alone application, and therefore of much wider interest. Essentially, it is a playback‑only sequencer that loads Standard MIDI files and then massages the data in various themed ways, termed 'styles'. Parameters that get altered in the name of style do not only include start times of the notes and their relative duration: far more expressive possibilities are created by the addition of MIDI controller data, such as volume, pitch‑bend, modulation, and panning. SE 2.1 also adds notes in some circumstances — for instance, a block chord played on a keyboard might be changed into a fingerpicking guitar motif using a more appropriate arpeggiated style. The included styles represent a distillation of many recorded performances by various musicians, playing a wide variety of instruments in different ways.

The output MIDI file incorporates little nuances that make the performance more human (Ntonyx call this Performance Modelling), and, once created, can be imported into your favourite sequencer. It all sounds a little too good to be true, but for anyone who cares to download the 'before and after' demos from the Ntonyx web site, the results are impressive. These are available in both GM/GS and XG formats, but would sound even better if used with longer samples.

Graphic Overview

Many styles generate new notes, as this composite screenshot demonstrates. The upper part is a simple block chord sequence, which has been transformed below using the 'Guitar 100P4/4G 30B Pop/Country Ballad filling' style. The result sounds like a true guitar player.

Style Enhancer 2.1 works with Windows 95, 98, and NT 4.0. You can download the full and demo versions from Ntonyx's web site; once you have made a secure credit card payment, the full version is unlocked with a personal password.

Style Enhancer's main display consists of a single window split into four main panes. At top left is the Tracks pane, which shows the name, MIDI channel, patch number, volume and pan settings of each horizontal track strip. To the right of this is the Measures pane, which shows note and controller data in a standard piano‑roll display very much like that of Cakewalk sequencers. Beneath these is the Note pane, with the Controllers pane at the bottom. These display the contents of the selected track in much greater detail, exactly like the Key Editor in most other sequencers.

There are two toolbars. The main one (above the Tracks and Measures panes) has buttons for filing (Open and Save) and editing (Copy, Paste, and Undo), followed by the four main function buttons — Filtration (for removing unwanted MIDI data), Quantising (for tweaking your timing), Modeling (sic; for choosing and applying styles), and Adjusting (more on this opposite). Next in line are the transport controls (Rewind, Play, Stop, Fast Forward, and Loop), a useful range of five Tempo buttons (x0.5, x0.75, x1.0, x1.5, and x2.0) for audition purposes, and finally a set of seven buttons that let you hide or show notes, velocity, expression, modulation, panning, and pitch in the Measures pane.

The second toolbar is beneath the Controllers pane, and contains controls for the Note and Controller panes. These include a section for Phrase Control (see later), a selection of Hide/Show buttons similar to that on the main toolbar, and a choice of editing tools. Select lets you draw a box around groups of events to select them for processing; Draw lets you add new notes, change the pitch, duration, or start time of existing ones, or change the current value of any controller, while Erase lets you dispose of unwanted notes or controller data.

Getting Started

There are fewer ensemble styles supplied than solo ones, but this one (Human Voice 100PS 05A Chords Slow Soft Back‑Vocal) shows how articulation is added using the MIDI expression controller.

Getting started with Style Enhancer is far easier than this multitude of controls suggests. You simply load in your standard MIDI file, and then click on the required track to select it. You can then select any or all of the track by dragging the mouse from left to right in either the Measures or Notes panes. The easiest way to audition styles is to make sure the transport Loop button is highlighted and then press Play to keep cycling round the selected track. You can also change the sound by clicking on the Patch entry for your chosen track and selecting a new instrument from the drop‑down GM list.

Before the style rules are imposed on the data Ntonyx recommend stripping out all MIDI controller information (including any inadvertent aftertouch), as well as setting the velocity of every note to the same value, and removing unwanted notes of very short duration: you can do all this using the Filtration option in the edit menu, which operates on all currently selected data. This helps to ensure that the program can perform its magic without having to work around existing nuances.

The Adjuster window is extremely useful for more general changes. The drop‑down list at the top shows every different type of MIDI data found in the current track, and the remainder of the window contains two groups of three vertical sliders. These show the Initial values (minimum, middle, and maximum), and the final Result values for the chosen data type. Depending on the type of data, you can drag these sliders to (for instance) change the overall key, expand or compress all velocity values, or change the tempo. If you make a mess you can Reset to the original values, while clicking on the Advanced button opens up a further section so that you can set values for both the beginning and end of the fragment or track. This allows you to add crescendos, diminuendos, rallentandos, and so on.

The Personal Touch

There are 30 styles in the supplied library, and these concentrate on sounds that are normally very difficult to emulate realistically in MIDI, such as breath, wind, and stringed instruments (see box for more details). However, although you can use these styles 'as is', the comprehensive selection of boxes in the Modeler window allows you alter any style to individual taste, and to suit the MIDI sound you are working with.

The Initial Parameters section determines what existing data is stripped out: Velocity, Expression and Panning can be forced to preset values, and any pitch‑bend and modulation data can be automatically deleted from the original performance. Ticking any of the Initial boxes allows this aspect of your data to be left alone, but by default most are unticked, allowing the values in the Assign boxes to be imposed instead.

Similarly, the Transformation Regulators panel (bit of a mouthful that) lets you tweak the amount of each aspect of MIDI transformation (start time, duration, velocity, expression, pitch wheel, modulation, and panning). Depth % controls the overall amount between 0 and 200 percent (where 100 percent is the default setting), and Random % can be varied between 0 and 30 percent so that each performance is slightly different. The Mute boxes allow each parameter to be individually excluded from the style changes, and the Clear button resets every box to its default condition.

Finally, at the bottom of the Modeling window is a comprehensive set of notes for each style, indicating suitable tempos, expression, and note ranges, along with suggestions for suitable GM voices and settings for pitch‑bend range (particularly important where fretless and slide techniques are used, since this determines tuning).

If you select Transformation from the Options menu, you can tweak MIDI parameters to suit a particular synth. The MIDI controller used for expression defaults to Controller 11 (Expression), but you can change this to 7 (Volume) if you or your synth prefer, or 2 (Breath) if you have a VL‑style physical modelling synth, or Brightness controller 74 if you prefer to add expression by altering the filter frequency. Auto Optimisation helps you thin out the potentially huge amount of MIDI controller data that could be generated, by letting you set a step value for various controller types, so that the inserted data resembles a staircase rather than a smooth ramp (in most cases, they sound almost identical).

For best results with many of the more complex styles, you really need to tell the program where the beginning and end of each musical phrase comes — for instance, real wind players need to take breaths, which often coincide with the end of a phrase. Both velocity and expression (and occasionally timing) parameters benefit from knowing how a track is phrased. You can add Phrase Markers using the toolbar mentioned earlier — the controls here let you move through the track note by note and mark the beginning and end of phrases — and you can also select a MIDI controller number to drop phrase markers automatically.

A Little Bit Of Style

Ntonyx supply 88 short MIDI examples that demonstrate the effects of different styles. Each is linked to one or more Styles in the help file, to show what can be achieved with suitable material. I started by loading in a lead guitar solo, which was initially devoid of any expression. The result of the lead guitar solo transform is shown in the screenshot on page 56 — all of the MIDI controller information shown (velocity, pitch bend and modulation) has been added by Style Enhancer. Notice that pitch‑bend has been used to slide or bend up to the correct note in many cases, and that vibrato largely bends the note higher rather than lower, just as a guitarist would. The result was certainly impressive, and even an accomplished keyboard player would find it difficult to match it using the pitch and mod wheels.

I then tried one of the guitar styles that generate additional note information. The initial MIDI data was about as simple as you can get: block chords, with every note at an identical velocity (as shown in the top part of the screen above). After Style Enhancer had done its work the result (shown in the lower part of the screen on page 56) looked and sounded totally different. Some very subtle pitch‑bend information had been added in a few places, but the biggest change was that the long notes of the original had been transformed into a very realistic chugging guitar rhythm — I was impressed!

Many of the supplied demos I tried were very effective, but of course the only true test is to try it out on your own music — so this is just what I did. Lead guitars were particularly effective, especially where several controllers were being generated simultaneously as in 'violining' using volume and real vibrato, while jazz guitar benefited from the automatic arpeggios generated by some styles. Wind instruments also responded well: after switching the Expression controller in the Transformation window to Breath Controller, I turned an existing VL70m flute line into a wonderfully evocative smoky jazz sax solo with loads of expression. Other solo brass parts worked well, but I had less success with solo violin. Some styles were also subtler than others.

The supplied library is reasonably comprehensive, and there are already five additional style sets on offer (each with a further mix of instruments). However, you don't have to use the styles on the suggested instruments. For instance, wind instrument styles should obey many of the same rules, since the length of a note and how vibrato is applied is dependent on the length of a human breath and the mechanics of tubes with holes. Similarly, any plucked stringed instrument could benefit from the rules supplied for guitars and basses, and any bowed string from those of the violin and fiddle. Of course, SE 2.1 isn't restricted to use with acoustic sounds: you can abandon conventions and create unworldly and bizarre transformations. Ntonyx even supply some of their own, like the Flip style that inverts the keyboard so that high notes become low ones and vice versa.

Conclusions

Overall, I found that if you started with a 'vanilla' performance, Style Enhancer 2.1 often provided a significant improvement (and was very successful in some cases). It was, however, less successful at improving tracks that already had MIDI controller data added by hand. I let SE 2.1 loose on several of my 'finished' tracks that already had 'hand‑crafted' MIDI controller information, and always preferred the original versions, but using SE 2.1 for inspiration with an 'in‑progress' track was nearly always successful. I did notice a few small bugs, and SE 2.1 would benefit from a few additions, such as horizontal and vertical zooming in the Measures pane, and Redo and History functions for easy before/after comparisons. However, this is nit‑picking, and for the first release this is truly an impressive product.

Style Enhancer 2.1 is based on a huge amount of research, and the impressive results reflect this.

Style Enhancer 2.1 will appeal to any musician who records MIDI using a keyboard, but wants to create more realistic‑sounding performances of acoustic instruments. It won't instantly convert your songs into masterpieces, but it can make a huge difference with the right material, especially if you are prepared to spend some time with it.

If Ntonyx were offering SE 2.1 at £99 or more I suspect they would sell quite a few, but at £37 this has to be an absolute bargain — especially with additional Style sets available for a further £15 each. Ntonyx have a winner on their hands here, and it just goes to show that despite the huge increase in hard disk recording, there's still lots of life left in MIDI. Style Enhancer 2.1 is based on a huge amount of research, and the impressive results reflect this. Adding style has never been this easy before — highly recommended.