Posted tagged ‘MIDI Sequencer’

TCM MASTERING: HOME MUSIC STUDIO PART 55 – MIDI CONTINUED

March 19, 2012

TCM Mastering: Home Music Studio Tips and Information

Part 55 MIDI Continued

In last week’s TCM Mastering Home Music Studio series, we looked at the various pieces of gear (Sound Generator, Interface, Controller and Sequencer) that are needed for a MIDI setup, as well as looking at the various MIDI messages and modes.

This week, we continue our look at MIDI by considering General MIDI. We’ll also delve into sequencing, recording and editing MIDI data.

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General MIDI

General MIDI (level 1) is a protocol that was developed in 1991 which defined specific features of a MIDI instrument. It means that the sounds on one MIDI instrument are largely consistent with the sounds on another MIDI instrument. In conjunction with the use of Standard MIDI Files (SMF), this means that a sequence created in one programme can be replicated or played back in another – the result should be that both sequences sound the same.

Writing Music With Pencil & Paper And With Finale Software.

The process of composing music these days is quite different to how it was done 100 years ago. There are many musicians of course who still compose the ‘traditional’ way, using pencil and paper. But for those musicians who never had much of a formal musical training, modern technology and particularly MIDI, allows them to create music by playing their efforts directly into a sequencer or computer and then adjusting or fixing any errors, without touching a pencil or piece of paper.

The Popular Sibelius Scoring Software.

What’s more, music can be created and recorded by a musician in one part of the world, then worked on or completed by a musician in another, without either of them leaving their studios.

Musicians On Opposite Sides Of The World Can Contribute To The Same Project.

For example, let’s say there are two musicians – Courtney in New York and Kurt who lives in London. They both have home studio setups with General MIDI compatible synths and sound modules. Using GM, Courtney can take the SMF of a song created in her programme, send it over the internet to Kurt who then plays it back on his system. The result is that the playback heard in the UK will (or should) sound the same as the version created in the USA.

It’s important to mention different programmes and sequencers often use proprietary file formats which may not be compatible with each other. For the example above to work, the file needs to be saved in Standard MIDI File format, which is usually an available option in most good sequencing programmes today.

In addition, not all MIDI instruments follow the GM standards. So if  this feature is likely to be important to you, then make sure the synth or other MIDI instrument you’re considering is GM compatible, before you buy it.

4 Families Of GM Instruments Each Containing 8 Patches.

General MIDI Level 1 protocols consist of…..

A minimum of 24 polyphonic voices which respond to velocity and 128 instrument patches. The 128 patches are divided into 16 family types, with 8 instrument patches in each family. For example, family #1 consists of piano type sounds whilst family #4 is guitars.

All 16 MIDI channels are supported for receiving and sending. Each individual channel is capable of playing a variable number of voices (polyphony) and can play a different instrument (patch or timbre).

Sound Patches Can Contain Several Different Instruments Spread Over A Keyboard’s Width. Here We See The Standard GM Key Assignments For Drums & Percussion.

Key-based percussion defaults to MIDI Channel 10. With each Note number (key #) corresponding to a different drum sound. For example, Note 35 is Acoustic Bass Drum, whilst Note 60 (middle C) is High Bongo.

In addition, General MIDI 1 is capable of handling a multitude of performance and controller messages.

General MIDI Level 2 was introduced in 1999. It is compatible with GM 1 and consists of…..

Over 380 sounds, 32 note polyphony, added features and greater control for sound editing and musical performance. A GM 2 device can handle 16 channels, up to 16 simultaneous instruments (patches) and 2 simultaneous percussion kits (on channels 10 and 11). Several more control messages were implemented, including MIDI tuning. Also added to the GM 2 standard were various effects, for example reverb and chorus.

Pro Tools MIDI Editor.

Sequencing

A MIDI sequencer works on the same principle as a multitrack recorder in some ways (except you never record to tape). There are the same transport functions – Record, Start, Stop etc. Each instrument is assigned and recorded to a separate track.

To differentiate between the various tracks, a separate performance can be assigned to one of 16 MIDI channels. Meaning that 16 different MIDI sounds or instruments (if you have that many) can be played back simultaneously – providing you have the right equipment (MIDI interface etc.) with enough Ins and Outs and a computer or sequencer with the processing power that is capable of handling it all.

In this way, the audio outputs from each instrument (synth or sound module) can be connected directly into a mixing deck (often part of the software programme or DAW that contains the sequencer) without ever going to tape and therefore are first generation sounds, giving you the cleanest of signals.

The sequencer can record the incoming MIDI signal in Real Time (as you play it) or Step Time (one note at a time), this signal contains the performance information for that recording – the note pitches, durations and volumes. No audio is recorded. To play back the MIDI recording, a MIDI OUT signal is sent to the synth or sound module where a sound is then triggered.

BeatDesigner – MIDI Plug-In Step Sequencer For Drum Patterns.

The advantages of recording performance information are…..

  • It allows you to record a track using a piano then play back that track information using any instrument you desire.
  • If you’re not the greatest player in the world, it allows you to record each note of a sequence one note at a time.
  • On play back you can alter the musical key of the performance from the original.
  • You can also alter the placement, pitch, volume or length of a note in the sequencer.

Recording

Prior to recording you need to make sure that all of your instruments, sound modules and sequencer/computer are talking to each other or synchronised.

You will need to…..

  • Decide which device is going to send MIDI commands – be the ‘Master’ and which devices are to receive commands – ‘Slaves’.
  • Check the polyphony setup for your instruments.
  • Assign MIDI channels for each device. For example, drum machines are usually set to channel 10, because this is the default channel for General MIDI.

If you play the ‘Master’ device and hear nothing from the other devices in your system, check through your setup. In particular, check the MIDI channel assigns (and of course you will need to monitor the audio outputs from each instrument in your system). Your specific instrument manuals should be able to help you with these setups.

Prior To Recording, You May Find It Useful To Sketch Out Your Setup If You’re New To MIDI, Noting Channels & MIDI Ins/Outs/Thrus.

Before recording, make sure you have the correct sound patch going to the right track and adjust the levels of the various instruments assigned to the various MIDI channels.

Your sequencer will have a metronome. If you choose to use it, you need to set the tempo and time signature…..3/4, 4/4 etc. Tempo can always be altered after you’ve recorded. You may find it useful to record at 60 bpm (beats/minute) if your playing skills are basic, but want the track to play back at 120 bpm.

Just make sure you decide on the final tempo before you start recording any audio. MIDI can be sped up and slowed down without altering the pitch. Audio cannot, without using pitch change plug-ins or software like Elastic Time and Pitch (see links below).

Editing

As with digital audio you can cut, copy and paste MIDI recordings. You can also easily quantise and transpose MIDI too. In recent years, big steps in audio manipulation software enable you to treat audio files in similar ways to your MIDI files. Check out Quantising audio with Elastic Time and Transposing with Elastic Pitch.

Left: Unquantised MIDI. Right: Quantised MIDI.

Quantising a performance can fix poor timing or rhythm. Let’s say you recorded a MIDI kick and snare from a synth keyboard, but on hearing back your performance, you feel it’s not quite tight enough – some of the beats stray a little.

You could manually move each drum hit to the correct position, but that might take a long time, especially if your performance is really bad! Alternatively, by setting the right quantisation value in your sequencer, you could hit a button and all the hits would snap to the correct beat.

If you choose a quantisation value of 8, then all your notes or drum hits would snap to the nearest 8th note. Choose a value of 16 and all the notes would move to the nearest 16th note. Most good programmes often have the added ability to somewhat or partially quantise – allowing a human feel to remain in your recording and preventing a robotic quality to the music.

If you’re rhythm is really out, there’s the risk that quantising the track will move some beats further out than in. It tends to work best for tracks that are slightly out. So listen carefully to the result. If it makes some beats worse, you may have to move those specific beats manually.

Transposed Music Sequence From A Major To E Major.

Transposing allows you to simply change your MIDI tracks from the key of A major to the key of E major, for example.

You may want to try out several vocalists for a song. Each one may have a different vocal range and consequently require the song to be played in a different musical key. Using the sequencer’s transposing facility enables you to change key at the touch of a button, without having to re-record your tracks.

Logic’s Piano Roll Editor Window.

In most good software programmes, MIDI can be represented graphically in a few different ways. The Piano-Roll Window tends to be the most common window used when editing. The picture above shows the piano keys represented on the left. The horizontal bars represent the different MIDI notes recorded on a track. The length of the bars shows how long each note was played. By selecting a note you can alter its position, length, pitch etc. Additional features allow you to adjust volume, change MIDI channels and more.

Logic’s Score Page.

When using Step Time to record one note at a time, some sequencers provide a Score Page where your musical performance shows up in musical notation. If you can read music this may be a useful page to work on and edit your MIDI tracks. It allows you to make all the alterations we’ve discussed earlier e.g. move notes, alter pitch, volume etc.

Events List Showing MIDI Data.

Some programmes include an Events List Window. Those of you who are techies will probably appreciate this page. It presents all the MIDI data of your music. Everything from velocity, pitch bend, pan and more.

So by using a combination of window displays, you can alter every nuance of a MIDI performance, even if the original lacked expression and dynamics.

Next week we look at Mastering, the final stage in the technical process of music making.

TCM Music Group and TCM Mastering provide full recording, mixing, mastering and production services from their facilities in the UK and Nashville, USA

Producing music takes time and effort. Give your music that final shine by using our online mastering service. TCM take pride in providing a professional, fast and affordable service to the music community.

Make Your Music Shine.

For more information, click here.

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TCM MASTERING: HOME MUSIC STUDIO PART 54 – MIDI CONTINUED

March 12, 2012

TCM Mastering: Home Music Studio Tips and Information

Part 54 MIDI Continued

Last week we considered – What is MIDI and what is it good for? This week we’ll continue by looking in some detail, at the type of equipment you will need for a MIDI setup.

We mentioned last week that various MIDI compatible synths, keyboards, sound modules, drum machines, computers and sequencers can ‘talk’ to each other. And that a MIDI interface is required when using a computer. So what part do all these various devices play and how do they work together?

Alesis Q25 USB/MIDI – 25 Keys, Keyboard Controller.

A basic MIDI setup will need…..

  • MIDI Sound Generator: This is what it says it is. It generates the sounds you will need for your music. It can be a synth, sound module, drum machine or sampler. The first synths equipped with MIDI were Sequential Circuits’ Prophet 600 and Yamaha’s DX7 (both in 1983). The latter became an almost instant hit, selling in huge numbers.
  • MIDI Interface: We briefly discussed the interface in last week’s blog. It allows your computer to receive and send MIDI messages.
  • MIDI Controller: These are devices that can control other devices. Initially, controllers were only keyboards. But today, there are controllers for keyboards, guitars, xylophones, drums and wind controllers for saxophones (and other wind instruments).
  • MIDI Sequencer: This device is often part of your computer software or DAW, but you can buy stand alone sequencers. It records the MIDI data and can also play it back. Remember, it’s not recording audio but the performance information.

Today’s equipment often combines one or more of the above MIDI essentials. For example, a particular synth could incorporate a sound generator, MIDI controller and sequencer, all in one device and maybe include a sampler too.

MIDI Sound Generator

These devices are the core to your MIDI setup. You will need at least one sound generator. However, if you’re home studio is mainly MIDI based, you will undoubtedly have several. As well as the hardware synths, modules and drum machines we’ve already mentioned, there are software synths and computer soundcards. Some sound generators are better than others. So let’s look at some in detail.

Korg microKorg Synth & Vocoder – Analogue Modelling, 37 Velocity Sensitive Keys.

Synthesisers

Synths consist of sounds which are generated and a keyboard to play them on. Synths vary tremendously in size, complexity and price. Compare Korg’s 37 key model above to the 88 key Nord Stage 2 Series 88 HA88, below.

If your MIDI setup is centred around a keyboard, you need to consider…..

Keyboard sensitivity or feel: the cheaper instruments normally tend to dispense with keys that are weighted. In other words, it won’t feel like a real piano keyboard when played. If you’ve been classically trained, a weighted keyboard may be essential for you. If you’re an enthusiastic but not very skilled player, you may be able to save some money by buying an instrument without. Try both types, then decide which you prefer.

The Incredible Nord Stage 2 Series 88 HA88 – Hammer Action Weighted Keyboard.

Quality of the sounds: most expensive instruments from respectable manufacturers have hundreds of fantastic sounds. But there are some synths at the cheaper end of the scale that have great sounds too. Listen to as many different synths as possible, in your price range, to determine which are your favourites.

One thing you might want to consider is General MIDI. This is a protocol which provides consistent sounds between different MIDI instruments and makes. We’ll look at it in more detail next week.

Polyphony: generally, the more keys you can play simultaneously the better. 32 note polyphony is common these days. It may sound like a lot – after all we only have 10 fingers – but you can use up those 32 notes quite quickly. Some synths have sound ‘patches’ that use several different samples layered on top of each other to produce the desired effect.

Let’s consider an extreme example, a synth ‘patch’ may include 4 different voice/choir samples and 4 separate strings layered to form a particular sound. That single sound patch has used up 8 of your polyphonic voices. Meaning your 32 note polyphony has just been reduced by a quarter, to 4! So always go for the highest polyphony you can afford.

Rick Wakeman In The Early Days – Surrounded By Keyboards.

Multitimbrality: most conventional instruments e.g. violin, piano, classical guitar only produce one timbre, one specific sound. Although, they are certainly capable of producing variations in tone. When synths first came out, they were able to produce very different timbres by twiddling or tweaking various knobs or sliders. But they could still only produce one timbre at any one time.

Rick In 2010. A Powerful, Modern Multitimbral Synth/Keyboard (Or Two) Can Effectively Replace A Whole Stack of Keyboards Or Other Instruments.

Today, some keyboards/synths can produce multiple timbres simultaneously. Either layering different timbres on top of each other or by splitting the keyboard up into distinct sections. So that the left hand can play a bass line whilst the right hand plays electric piano, for instance.Think of a multitimbral synth as one instrument containing several specific instruments, with the ability to play multiple instruments simultaneously.

Of course the concept of multitimbrality ties in directly with polyphony. The more timbres you use at any one time the quicker you use up your polyphonic voices.

But it has become almost standard in many quality synths today. So again, when testing out synths/keyboards consider multimbrality and polyphony together. One affects the other.

When looking at how this all fits in with MIDI, most modern instruments will accept data on all 16 MIDI channels simultaneously. Some synths allow you to dynamically allocate voices which means providing you don’t want to use all your voices all the time, the synth’s resources will go much further.

The Classic Korg Triton Synth – 62 Voices & Built-In Sequencer.

Sequencing: some synths come with built-in sequencers. These instruments allow you to record and play back (or programme) multiple tracks of a performance. Essentially, they’re complete mini studios.

Manufacturers’ designs can be quite different. So take a close look at the various options on the market to see which instrument/sequencer combination works for you. Some are more user friendly than others.

Roland SP-555 Sampler & Pattern Sequencer.

Instead of generating sounds like a synth, Samplers are sound modules containing short audio ‘samples’ of real instruments e.g. violin, sax, drums or sound effects e.g. explosions, dog barks or gunshots. These samples are then played back on a keyboard or triggered by a sequencer.

You could for example, sample (record) percussive sounds like a car door closing, a pane of glass smashing or someone coughing and use them to enhance a drum track. These sounds and many more (you wouldn’t normally associate with music) have been used for just that purpose.

Logic EXS24 Sampler.

There are hundreds of Soft Synth plug-ins available for use with your music software or DAW. Although not all plug-ins work with every music/recording programme. These software equivalents of stand alone synths and sound modules are usually cheaper because there’s no hardware cost involved.

The Boss DR-880 Dr Rhythm Drum Machine.

Drum Machines

Many drum machines contain several different drum sounds and have a sequencer which allows you to programme those sounds into song patterns. Sounds are usually produced by hitting pads designated for kick, snare etc.

A Small Part Of A Drum Patch On Keyboard, With Instruments Assigned To Specific Keys – Showing Hi-Hat, Kicks, Snares, Crash, Ride & Tom.

Most good synths or sampler keyboards contain a few drum ‘patches’ that can be spread across the entire width of the keyboard. A drum patch could start with various kicks assigned to the low keys, snare hits and rolls next, then toms, cymbals and hi-hat towards the upper keys. Maybe a few percussion instruments at the top end of the keyboard e.g. tambourine, cow bell etc.

Sound Modules

Think of a synth without a keyboard. Or a drum machine without pads to strike. Sound modules provide the sounds but are triggered by a sequencer, master synth or other type of MIDI controller. They tend to be very compact and cheaper than their keyboard equivalents. So if you have a good quality master keyboard controller, you can set up a few sound modules in a daisy chain to work with it.

M Audio USB MIDISPORT 8X8.

MIDI Interface

As we saw last week, MIDI Interfaces can be quite basic In/Out boxes or provide numerous Ins and Outs for more complex setups, like M Audio’s box above. The connections are usually either 5 Pin-DIN or USB. Connections for modern Mac computers tend to favour USB. PCs use USB or sometimes parallel ports. Whatever your setup there’s a connector and interface out there that can hook you up.

Yamaha WX5 Wind MIDI Controller.

MIDI Controller

The most popular MIDI controller is still probably the keyboard. But guitarists, drummers and wind players can also be part of the wonderful world of MIDI. The MIDI controller can be regarded as the ‘master’ that controls the ‘slaves’, which can be other synths, sound modules or a drum machine. The controller can also be a sequencer or computer.

MIDI Sequencer

Logic, Cubase, Pro Tools and other good programmes include a sequencer. There is no unanimous agreement as to which one is best, so you should check out as many programmes as possible to see which one suits your style of working.

You can buy stand alone sequencers and some synths/keyboards also include on board sequencing.

Pro Tools MIDI & Audio Tracks Alongside Each Other.

The software programme choice usually provides the most comprehensive facilities. Being able to view your MIDI tracks alongside any audio tracks your session may have on a good sized screen is invaluable. Editing and other options are typically more extensive too.

MIDI Messages

We looked at Performance data last week. This information pertains to note-on/off, velocity, after touch, pitch bend and vibrato messages.

As well as the performance data, there are other messages that MIDI can communicate. Control Change messages deal with expression data. For example, volume, pan and modulation.

System Common messages provide information on which MIDI channel the performance data should be sent to and which sound or ‘patch’ should be played as well as data on timing, master volume and effects settings.

System Exclusive messages deal with data about a specific device.

In a live performance or a studio setting where you may have only one sound generator, MIDI can select different sounds at different points in a song e.g. ‘Super Electric Piano’ for the verse and ‘Rock Piano’ for the chorus.

MIDI Modes

There are four operating modes which can affect the way a device (synth, sound module or drum machine) responds to MIDI messages.

Mode 1: Omni On/Poly – your synth will play polyphonically but ignores MIDI data. In other words it will try to play whatever you send it on whatever channel.

Mode 2: Omni On/Mono – this is the mono equivalent of Mode 1. This Mode is not commonly used, but is sometimes useful if you want a polyphonic synth to emulate an old mono synth. Messages from any of the 16 MIDI channels are all sent to the same voice.

Mode 3: Omni Off/Poly – in this mode the synth plays polyphonically but only responds to messages on its own MIDI channel. This is the most commonly used mode, especially if a sequencer is involved.

The Mode 3 diagram above, shows the recipient device is assigned to MIDI channel six. MIDI channel messages received can then be rendered polyphonically.

Mode 4: Omni Off/Mono – this is the mono equivalent of Mode 3. This Mode was more useful before multitimbral synths came along, allowing some early MIDI synths to play 4 different sounds over 4 separate MIDI channels. Although it is still commonly used by guitar synth players who assign each string to a separate MIDI channel.

MIDI can be a really ‘deep’ subject. But you don’t have to know it inside out to be able to make good use of it. Start out with a simple setup and add to it as your knowledge and experience grows.

Next week we’ll look at General MIDI, sequencing, recording and editing MIDI data.

TCM Music Group and TCM Mastering provide full recording, mixing, mastering and production services from their facilities in the UK and Nashville, USA

Producing music takes time and effort. Give your music that final shine by using our online mastering service. TCM take pride in providing a professional, fast and affordable service to the music community.

For more information, click here.

Make Your Music Shine.