Transient emphasis что это

Maximizer

Overview

Ozone’s acclaimed IRC (Intelligent Release Control) technology lets you boost the overall level of your mixes without sacrificing dynamics and clarity. The Maximizer applies to the entire bandwidth of the mix; it is not a multiband effect.

The module interface includes the following main sections:

Module Header

The module header area includes the following controls:

Not Recommended for Loudness Compliance

Learn Threshold should not be used to meet loudness compliance standards.

Views

You can toggle between the different views using the view selector buttons in the module header area.

The Maximizer module includes the following views:

Spectrum Analyzer

Displays the magnitude (amplitude, in decibels) of a signal across the frequency spectrum in real-time. The spectrum analyzer displays the output signal of Ozone.

Gain Reduction Trace

Displays a scrolling waveform with a superimposed trace reflecting the amount of gain reduction applied over time.

Controls

The Maximizer includes the following controls:

The Maximizer includes the following Intelligent Release Control (IRC) modes:

Threshold

Adjust the threshold of the Maximizer to set the level at which the limiting processing takes place and determines the amount of gain added to maximize the output level.

Threshold and Maximizer Output

The threshold control includes the following sub-controls and meter:

Threshold Meter

Displays input level and applied gain reduction.

Ceiling

Adjust to set the maximum output level of the Maximizer.

Ceiling, Dither, and Codec Preview

Threshold and Ceiling Link

Enable to link the Threshold and Ceiling controls. Adjusting either control in linked mode will adjust the other control by the same amount and vice versa.

True Peak

When enabled, the limiter will account for the levels of each digital sample and the levels of the analog signal that will eventually be produced by D/A conversion. Enables the limiter to take into account not only the levels of each digital sample but also the levels of the analog signal that will eventually be produced by D/A conversion. This is sometimes necessary, since an analog signal’s peak level can exceed the corresponding digital signal’s peak level by more than 3 dB.

True Peak Limiting & CPU Usage

This option will result in a small increase in CPU usage, but if your mixes are running very hot you may want to enable it to ensure that absolutely no distortion is introduced when your audio is finally run through a D/A converter.

Character

Adjust to customize the overall response time (attack and release times) of the maximizer processing. The attack and release times used are dependent on the selected Mode, and allows a continuous range from Fast (0.0) to Slow (10.0) in each mode.

Stereo Independence

Transient Emphasis

Enable Transient Emphasis adjustment by clicking the Transient Emphasis power button. Adjusting the Amount control allows you to fine-tune the shaping of transients before limiting takes place. This can be useful for preserving sharper sounds, like drums, while still optimizing loudness.

Transient Emphasis Settings

Using higher amount values for Transient Emphasis will result in more pronounced transients after the limiting process.

Источник

Динамическая обработка звука

Динамическая обработка представляет собой процесс изменения динамического диапазона сигнала – разницы между самым громким и самым тихим участком аудиосигнала.

Динамическая обработка в современном продакшене является неотъемлемой частью процесса сведения. Если проанализировать популярные композиции в танцевальной стилистике, то можно отметить, что они звучат очень «громко» (правильнее сказать плотно). Такой эффект «громкого» звука – это следствие сужения динамического диапазона сигнала и последующее повышение уровня сигнала (увеличение среднеквадратического значение уровня сигнала – RMS).

RMS (root mean square) – среднеквадратическое(средневзвешенное) значение.

Динамическая обработка в большей степени применяется для упрощения процесса изменения громкости различных участков сигнала. Такую обработку также можно выполнить, используя автоматизацию громкости. Однако в некоторых случаях это занимает слишком много времени. Поэтому не является целесообразным.

Все процессоры динамической обработки, в той или иной мере, применяются для изменения уровня сигнала на определённых участках аудиосигнала.

Основными устройствами динамической обработки звука являются:

Рассмотрим подробнее каждый прибор.

Компрессор

Это самый часто используемый прибор динамической обработки. Он предназначен в основном для сужения динамического диапазона сигнала. Однако его применение этим не ограничивается. Часто компрессор применяется для выделения атаки сигнала, сайдчейн компрессии, склеивания инструментов в группах, а также для создания необычных эффектов.

Классический компрессор имеет следующие параметры:

Threshold – порог срабатывания (дБ). Если обрабатываемый сигнал превысит этот порог, то компрессор включится, и будет обрабатывать сигнал в соответствии с настройками.

Ratio – коэффициент компрессии или степень компрессии (относительная величина: 2:1; 3:1; 4:1 и т.п.). Показывает во сколько раз будет сжат сигнал, который превышает порог срабатывания. Например, если уровень сигнала — 4 дБ, порог срабатывания — 8 дБ (8-4=4 дБ), степень компрессии 2:1, то разница между уровнем сигнала и порогом срабатывания будет сжата в два раза (4:2=2 дБ). Таким образом, после компрессии уровень сигнала уменьшится на 2 дБ и будет составлять 6 дБ.

Attack – время срабатывания (мс). Указывает компрессору как быстро после превышения порога срабатывания необходимо сжать сигнал. Это время от момента превышения порога срабатывания до момента максимальной компрессии («плавность начала компрессии» если так можно выразится). Можно провести аналогию атаки огибающей и атаки компрессора.

Release – время восстановления (мс). Указывает компрессору, как быстро необходимо перейти в режим ожидания (выключится). Этот параметр отображает плавность выключения компрессора (по аналогии с параметром восстановления огибающей).

Make Up (Gain) – компенсация громкости на выходе компрессора (дБ).

После компрессии уровень сигнала снижается (в вышеприведённом примере на 2 дБ) в соответствии с настройками компрессора. Параметр Make Up позволяет скомпенсировать потерянную громкость.

Нужно отметить, что компрессор сжимает сигнал превышающий порог срабатывания (уменьшая его), при этом самые тихие участки (не превышающие порог) остаются без изменений. После компенсации громкости максимальный уровень возвращается на своё прежнее значение, при этом повышается уровень и на всех остальных участках сигнала (тихие участки становятся громче). Такая процедура сужает динамический диапазон сигнала. Это позволяет сделать аудиосигнал более читаемым в миксе.

Компрессоры различаются по алгоритму работы и функциональности. Также существуют многополосные компрессоры, позволяющие отдельно компрессировать различные частотные диапазоны (полосы) сигнала. В таких компрессорах для частотного разделения сигнала используется кроссовер.

Многополосный компрессор iZotope Ozone 7 Dynamics

Для большего понимания предлагаю посмотреть видео «Что такое компрессия звука?».

О том, как настаивать и использовать компрессор читайте в статьях:

Транзиент шейпер

Этот прибор представляет собой урезанную версию компрессора, предназначенную для работы с временными параметрами сигнала (Attack и Release). Классический транзиент шейпер позволяет увеличивать уровень атаки и восстановления сигнала в соответствии с выбранной кривой.

Ярким представителем этого класса устройств является плагин Transient Shaper 2 от компании Schaack Audio Technologies.

Transient Shaper 2

Чаще всего транзиент шейпер используется для усиления атаки.

Лимитер и максимайзер

Лимитер представляет собой компрессор со степенью компрессии ∞:1. Задачей лимитера является ограничение сигнала превышающего установленный порог. Этот прибор имеет те же параметры, что и компрессор (Threshold, Attack, Release и Gain).

Максимайзер – это лимитер с автоматической компенсацией громкости. Это устройство позволяет повысить уровень сигнала на мастере, при этом избегая клиппирования.

Это прибор, который позволяет избавиться от различных шумов. Гейт (gate – с англ. ворота) пропускает сигнал, который превышает порог Threshold и не пропускает сигнал ниже этого порога.

Гейт часто используется при обработке вокала или других инструментов записанных вживую.

Основными параметрами гейта, являются:

Threshold – порог ограничения (дБ). Если сигнал опускается ниже этого порога, то гейт не пропускает этот сигнал (сигнал подавляется). Все что выше порога остаётся без изменений.

Ratio – коэффициент подавления (относительная величина). Показывает насколько сильно сигнал будет подавлен.

Attack – время срабатывания гейт (мс). Насколько быстро (плавно) будет подавлен сигнал.

Release – время восстановления (мс). Насколько быстро (плавно) будет восстановлен сигнал или как скоро полностью выключится гейт после того, как уровень сигнала превысит порог ограничения.

Одним из лучших гейтов на сегодняшний день является FabFilter Pro-G.

Экспандер

Это прибор, выполняющий противоположные компрессору функции. Он позволяет увеличить динамический диапазон сигнала (разницу между самым громким и самым тихим участком).

Существует два вида экспандеров – понижающий и повышающий.

Первый понижает уровень сигнала ниже установленного порога, а второй повышает уровень сигнала выше заданного порога.

Основные параметры понижающего экспандера:

Threshold – порог срабатывания (дБ). Если уровень сигнала будет ниже порога срабатывания, то экспандер включится и ослабит сигнал, не превышающий этот порог в соответствии с настройками.

Ratio – коэффициент ослабления (относительная величина). Показывает, во сколько раз ослабится сигнал, не превышающий порог срабатывания.

Attack и Release – время атаки и время восстановления (мс) (аналогично компрессору).

Основные параметры повышающего экспандера:

Threshold – порог срабатывания (дБ). Если уровень сигнала будет выше порога срабатывания, то экспандер включится и усилит сигнал, превышающий этот порог в соответствии с настройками.

Ratio – коэффициент ослабления (относительная величина). Показывает, во сколько раз усилится сигнал, превышающий порог срабатывания.

Attack и Release – время атаки и время восстановления (мс)(аналогично компрессору).

В качестве повышающего экспандера может быть использован компрессор Waves С1 comp с коэффициентом компрессии от 0,5:1 до 0,99:1.

Деэссер и депоппер

Деэссер – это прибор, который позволяет автоматически устранять шипящие звуки в вокальных партиях в соответствии с настройками.

Для того, чтобы не исправлять шипящие в вокальной партии с помощью автоматизации часто прибегают к помощи деэссера. Однако необходимо отметить, что автоматизация всё же является более приемлемым вариантом (хоть и занимает больше времени).

Депоппер – это прибор, который призван подавлять бубнящие звуки в вокале.

По сути деэссер и депоппер работают по одному и тому же принципу.

Одним из самых популярных деэссеров является FabFilter Pro-DS.

Ещё одним вариантом устранения огрехов вокалиста (шипящие и бубнящие) является использование динамической эквализации.

О том, что это такое читайте в статье «Что такое динамическая эквализация?».

Как я уже говорил, все приборы динамической обработки призваны автоматизировать и ускорить процесс обработки сигнала (выравнивание динамики, выделение атаки, устранение шумов и т.п.).

При сведении композиции динамическая обработка является необходимым этапом, даже если она выполнена без использования вышеописанных устройств.

Источник

Maximizer

Overview

Ozone’s acclaimed IRC (Intelligent Release Control) technology lets you boost the overall level of your mixes without sacrificing dynamics and clarity. The Maximizer applies to the entire bandwidth of the mix; it is not a multiband effect.

Controls

MODES

IRC LL

Provides the intelligent loudness maximization of IRC I with lower latency.

IRC I

Provides intelligent digital loudness maximization of the signal. It does this by analyzing the source material and applying limiting in a psychoacoustically pleasing manner, reacting quickly to transients (to prevent pumping) and reacting more slowly to steady bass tones (to prevent distortion).

IRC II

Similar to IRC I, but optimized to preserve transients even more, so they sound sharper and clearer in the output signal, even when aggressive limiting is taking place.

IRC III

Allows for the most aggressive limiting by using an advanced psychoacoustic model to intelligently determine the speed of limiting that can be done to the incoming signal, before producing distortion that is detectable to the human ear.The IRC III mode is very CPU-intensive, and produces a high latency, especially at higher sampling rates. You may find that at sampling rates greater than 48 kHz you are unable to use Intelligent III mode in real-time. The IRC modes provide intelligent release control (the release time is automatically varied depending on the audio material). However, when the Maximizer is set to IRC III mode you may also choose between four different character “styles,” which will help you manage the limiter’s sound by constraining its release behavior.

IRC III Styles

IRC IV

This mode builds upon our existing IRC technology by shaping the spectrum to further reduce pumping and distortion. As the signal goes farther over the threshold, the IRC IV algorithm limits frequency bands that contribute most to these peaks. This reduces intermodulation between different signal components. For example, given vocals and drums, this algorithm can be more selective about limiting the transients from the drums, without causing the vocals to duck as much. When no limiting is necessary, the spectrum will be unaltered. While a typical multiband limiter has only a few bands set using crossovers, Ozone’s IRC IV algorithm uses dozens of psychoacoustically spaced bands in order to react to any type of audio.

IRC IV STYLES

THRESHOLD

LEARN THRESHOLD

When enabled, the Maximizer will automatically adjust the Threshold slider to in response to the input audio in order to meet the Threshold Target value defined below. Double-clicking the Target LUFS value readout allows you to edit the LUFS target.

This parameter will not disable itself after learning. It can be used to continuously update the Threshold to meet the Target value.

Learn Threshold is not recommended for loudness compliance purposes

The Learn Threshold control is not intended to be used to meet loudness compliance standards.

CEILING

THRESHOLD & CEILING LINK

Links Threshold and Ceiling control values, when linked the controls

TRUE PEAK

Enables true peak limiting by examining not just the levels of each digital sample, but the levels of the analog signal that will eventually be produced by D/A conversion. This is sometimes necessary, since an analog signal’s peak level can exceed its corresponding digital signal’s peak level by more than 3 dB!

This option will increase CPU usage slightly, but if your mixes are running very hot you may want to enable it to ensure that no distortion is introduced when your audio is finally run through a D/A converter. Many modern broadcast loudness standards impose a limit on true peak levels, so use this option to ensure compliance of your peak levels.

CHARACTER

Adjust the character slider to customize the overall response time of the maximizer processing.

Stereo Independence

When limiting channels independently (with both sliders set to 100%), it is possible to achieve a louder output from the Maximizer, but this can result in a narrow stereo image. To alleviate the narrowing effect of the Stereo Unlink control, we split this feature into two sliders.

When set to non-zero values, these controls apply limiting to transient and sustained material separately, based on a level envelope generated from a ratio of the individual channel levels and the entire stereo image.

TRANSIENT

Adjusts how the Maximizer limits transient material across channels.

SUSTAIN

Adjusts how the limiter responds to sustained material across channels.

LINK

Links the Transient and Sustain sliders.

TRANSIENT EMPHASIS

Click the “Transient Emphasis” button to fine-tune the shaping of transients before limiting takes place; this helps to preserve sharper sounds like drums, while still optimizing loudness.

The higher the amount of transient recovery you dial in using the fader, the more pronounced the transients will be after the limiting process.

Meters

THRESHOLD METER

The Threshold meter displays gain reduction as it is taking place with level meters. The outer two meters display the levels of the incoming signal; as gain reduction begins to take place, a gain reduction meter appears in red between the two level bars.

MINI-METERING VIEWS

The Maximizer includes mini-metering views above the controls area.

Gain Reduction Trace

A scrolling meter that displays the incoming signal’s waveform with a superimposed tracing that illustrates the amount of gain reduction taking place in real-time. The Gain Reduction Trace can help you to set attack and release controls appropriately and monitor the envelope of gain reduction.

Источник

An Introduction to Limiters (and How to Use Them)

Get the highest quality sound every time

Music Production Suite Pro

Explore the future of mastering:

Ozone 9

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This article is all about limiters—when to use them, how to use them, and how to train your ears to tell if they’re mangling your original sound source. But first, we need to define what a limiter actually is.

Scour the internet and you’ll see a host of definitions when it comes to limiters. Most agree on the specs: it’s essentially a compressor with a ratio of more than 10:1, though I’ve seen 8:1, 20:1, 100:1, and ∞:1 bandied about.

I’d like to argue that a limiter is defined as much by its purpose as its specs, and here’s why:

We compress for many reasons. We might want to shape the feel of an instrument or shrink its dynamic range into a more manageable space. We may compress for color as well.

In this piece you’ll learn:

Want to try what you learn? Experiment with limiters in Ozone Pro for free by signing up for a free trial of Music Production Suite Pro.

What is a limiter?

A limiter, however, is usually used for one reason: to catch the loudest moments of a source, bringing them down in a way that a) protects against unwanted distortion, and b) maintains the integrity of the mix’s overall balance/color.

To put a button on it (or in this case, four buttons, all in): Your UA 1176 compressor is capable of reaching ratios over 10:1. But would you put it on your master bus? Probably not, as it would color the tonality of the whole mix.

Questionable side effects

People often use limiters to increase the overall level or loudness of an instrument (or more frequently, groups of instruments). But is this the best use of them?

That’s up for debate. Some engineers prefer not to juice the input gains or thresholds of their limiters, choosing instead to treat the signal as much as possible before it hits the limiter. They use gain boosts, EQ, and compression to achieve the proper tone and desired level before utilizing the limiter to catch peaks.

Other engineers rely on the limiter’s ability to drive an input signal against the output ceiling. Others still might run two limiters in series, boosting only a little into the ceiling with each one.

As long as it sounds good, any approach is valid; the trick is to make sure you know it sounds good. It’s easy to be fooled in the moment.

When to use limiters

You may find yourself using limiters on peaky instruments that otherwise sound fine (metal drums come to mind) when mastering. Vocals, which can also spike suddenly, are subjected to limiting here and there as well (Nectar Pro sports a switchable limiter).

Still, the majority of limiter-talk tends to center on the master bus, and this makes sense: Limiters are ubiquitous at the end of the mastering chain.

Think of the limiter as a bouncer, standing just outside the door of a club, keeping harsh digital overs outside of the proceedings, and doing so with the force of a brick wall, which brings us to…

Brickwall limiters

These limiters operate with infinitely high ratios, always implementing a delay in the signal in order to see any peaks coming down the pike. Sometimes you can tweak how far the limiter peers into the distance with a dedicated lookahead parameter. Sometimes this parameter is off-limits to the user.

Whichever kind of limiter you have, know that it may not protect against clipping, and your metering might not show the clipping unless it’s designed to display these ‘true peaks’.

Some digital limiters aren’t configured, out of the box, for catching the peaks that might occur between digital samples (intersample peaks). For that, you can switch to a mode specifically programmed to catch intersample peaks (commonly referred to as “ISP” or “True Peak”).

True peak operation

Within the last few years, true-peak technology has become de rigueur for any modern limiter to compete—and many limiters now offer it as a selectable option.

There is, of course, a more controversial point to make: yes, many mastering engineers use true-peak limiters—but plenty of engineers dislike ISP limiters, claiming their sound affects the material in a deleterious, adverse way.

Some would rather lower the output ceiling to ensure nothing got past 0 dBFS than submit a louder master with a true-peak limiter deployed. Others don’t even care about true-peak distortion at all.

Indeed, take your favorite tunes from the last five years and put them through iZotope RX. Click on Waveform Stats. I can guarantee that many of your favorite tunes easily clip past 0 dBTP.

Personally, I go on a case-by-case basis, depending on the needs of the client and the needs of the song. On a recent EP I mastered for the artist Peach Face, one tune didn’t take to ISP limiting so well, while another was improved by the addition of the ISP setting on Ozone.

Whether or not you want to use true-peak limiting is up to you or your mastering engineer. Strictly speaking, I can tell you this: use true peak whenever you want to make absolutely sure there is no clipping when your audio is run through a D/A converter.

Common controls in mastering limiters

Limiters can come with attack and release controls, but not all of them do. As a matter of fact, their GUIs can appear vastly different, depending on the brand. Some limiters have threshold sliders dictating the level at which gain reduction begins; these sliders also affect the corresponding output gain, and as such, the signal seems louder the more you pull these sliders down. Other limiters ditch the threshold control altogether, showing you only input gain; these increase the level—and gain reduction—the more you push them up into the digital ceiling.

The mechanics of your limiter may vary, but the overall tools are the same: a parameter dictating your highest possible level in dBFS (commonly called the “ceiling”), a knob/slider that determines the amount of gain reduction—one that is similar to a compressor’s threshold (quite often, this parameter makes the signal feel “louder”) and a time constant of some kind; this is usually a release control, though sometimes attack is offered as well.

Some limiters offer stereo linking controls, the manipulation of which can have an effect on the width of your mix. Left totally unlinked, both channels will be limited independently, causing each channel or the other to dip in level on its own. This can create an interesting sense of width, because each side of the stereo image is reacting differently to the limiter, drawing the ear in different directions. When pushed too far, unlinked limiting can cause the stereo image to wander in distracting, unpleasant ways.

Conversely, you can often opt to link the left and right channels, in which case the louder one, regardless of its stereo placement, will trigger gain reduction across the board. This creates a more uniform stereo image, as you aren’t hearing those variances in the left and right channels.

Often degrees of linking are provided, usually in percentages. Your ears will ultimately be the judge of what sounds best here.

Ozone Pro’s Maximizer, which handles the limiting duties in iZotope’s heralded mastering suite, offers two stereo controls, one that focuses on the transient portion of the signal, and another that centers on sustained material over time. You’ll also note their Transient Emphasis slider, which handles transient preservation before the limiting stage.

To better hear how these work, try implementing the exercise we’ll outline in just a moment.

The rhythm of algorithms

These days, limiters often employ selectable algorithms to better suit your individual music, some of which deploy sophisticated multiband technology under the hood. Take some of Ozone’s venerated IRC algorithms, for example.

IRC stands for “Intelligent Release Control,” and to some extent, IRC will preserve the dynamics and overall clarity of your mix. Now, with so many different IRC settings—four overall, with separate “styles» in IRC III and IRC IV—it can be tough to know which is best for the music at hand. Luckily, most companies offer manuals to explain their algorithms, and iZotope is no exception, providing a detailed explanation of IRC in their documentation.

Where does multiband come in? That would be IRC IV, which uses a multitude of bands, rather than three or four, as you would’ve seen in the conventional, multiband limiters of yesteryear. IRC IV’s bands are split up in a psychoacoustic way to better serve the material at hand, resulting in a more transparent and natural effect.

All of this is well and good, but how do you actually use a limiter to your advantage? After all, if set wrong, limiters can introduce their own distortion, as well as unpleasant side effects on the groove.

How to hear the difference in 4 easy steps

Here’s a step-by-step guide for tuning your ears to the sonic specificities a limiter imparts on your mix. I usually go through some iteration of this process every time I demo a newly-released limiter.

1. Link the limiter’s input and output as you tweak

Many limiters allow you to link the input gain or threshold control with the output ceiling, so that as you push one, the other comes down in level. This way, your ears won’t be fooled by a satisfying jump in loudness, and you can better judge the moment you’ve gone too far.

Ozone Pro has a linking feature that pairs the threshold slider to the ceiling. Turn that on as you pull the threshold down. At some point, you’ll hear audible distortion. Stop here and pull back until you don’t hear the distortion anymore.

Now you’re ready for step 2.

2. A/B between gain-matched bypass and limited signal

Compare the limited signal with its bypassed variant, carefully noting the differences in timbre. Does the track feel narrower with the limiter on? Are the transients pillowy, softer, or otherwise altered? Does the groove of the whole piece seem different? Note your generalized findings, and write them down if that helps you (it helps me with internalization).

3. Set up a delta test

This is where things get fun—and depending on the limiter, a bit tricky. We’re defining “delta” here as the real-time difference between your limited mix and bypassed version. It’s similar to soloing the esses of a de-esser (where you’d only hear the ess), or the noise output of a de-noiser (where you’d only hear what it’s removing).

Isolating and soloing these artifacts will call attention to them. Hearing them apart from the mix will tune your ears to what’s missing from your limited material once you switch it back on.

It’s a bit like training yourself to hear the effects of MP3 encoding using Ozone’s codec simulator: Once you hear what the encoding takes out of the original mix, those weird, lossy qualities of MP3s reveal themselves. The same general principle underscores this exercise.

Some limiters offer specific delta parameters, but not all do. Luckily, you can make your own with some clever routing, multiple instances of a limiter, and a plug-in that flips polarity.

Please note: different DAWs handle latency in different ways, so you may need to experiment for your own purpose in order to create a true A minus B listening test. Luckily, the workflow is roughly the same in Logic Pro X and Pro Tools, two of the more common DAWs.

First, kill the output of your source track, selecting “no output” (or whatever variant of that terminology your DAW provides) in the output section. Next, route the source to two auxiliary channels on two sends. Duplicate the limiter to both auxiliary channels, and bypass the limiter on your source track. On the second channel, flip the limiter itself into bypass.

Logic users take note: Do not use your DAW’s global bypass, but rather, the plug-in’s own bypass parameter.

Next, load any utility plug-in after the limiter that flips the phase of both the left and right channel.

Logic users, I cannot stress this enough: it’s essential for you to have both limiters instantiated for the trick to work, or else latency will be an issue, and you won’t hear what you’re supposed to hear—the sporadic limiting of your mix, usually on the kick and snare drums, when the limiter is audibly pushing down on signal.

A final note on delta tests: there are plug-ins that can actually set up delta tests for you, so you don’t have to go through all this routing yourself. Some of them are exceedingly cheap as well.

By way of example, here’s a snippet of music:

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