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Programming natural sounding grooves

Listen to where this tutorial can take you!  MP3  

On the Midi programming page we looked at some of the compositional structures of Cuban style grooves and saw how simple a lot of the basic rhythmic components could be to program with MIDI. This month we will look a little into that elusive topic of natural feel. One of the characteristic things about Latin and Ethnic drum and percussion grooves is the elusive feels of the rhythms. A lot of ethnic percussion styles have their own built in feels which are difficult to pin down in an absolutely accurate and precise way. Anyone familiar with the Samba grooves of Brazil will know exactly what I mean when I embrace this topic. Surprisingly, when you see these type of rhythms written down they appear fairly straightforward, made up of predominantly straight sixteenths. When you listen to them though, they sound anything but straight, with a very lilted feel, much like the un-even roll of an egg. It is a mysterious and annoying thing as a budding percussionist that even when you can play the strokes on the drum in the right order and with the right technique, it can still sound wrong. It is also quite often the case that particular styles play very behind or ahead of the beat, sometimes only in particular places in the bar or on particular notes. Up tempo folk grooves from North India for example may be slightly ahead and anticipating whilst a slow Latin ballad may be slightly behind the beat. A classical Tabla part meanwhile might have just one note in each bar that is ‘pulled back’ in a very idiomatic way. This type of thing really stands out with instruments such as Bongos and Tabla where some of the strokes can be very short and staccato and become prominent if they do not sit in rhythmically when used out of their natural context. For any musician, it really takes years to get inside of these rhythms and truly understand the grooves and the way they can be manipulated with elasticity. Another aspect of this is the ambiguity which can be inseparably bound within a rhythm. African drummers are masters or throwing the listener off by stating contrary cross rhythms in a groove to create a feeling of rhythmic tension. It is all these factors that meld together to give it that spice and feel.

This all creates a number of problems for the would be percussion programmer who does not want to quantize everything as a first step. Firstly there needs to be a way to program a groove which has an ethnic feel and then get the other elements of the groove and song to sit with it rhythmically. Secondly, working the other way around, there could be a great ethnic feeling percussion audio part which is exactly the right sound for your song but which won’t blend rhythmically with the material already programmed.  This time we are going to use processed audio files and not MIDI programmed single hits. We are going to build up a multi track percussion part similar in construct to the MIDI programming page, using individual instruments derived from audio files. We will do this by making a set of Re Cycle files from trimmed audio loops, importing them into the EXS24, building a set of sampler instruments and extracting the MIDI files into the song within Logic.

I am using some audio files from my collection but obtaining source material on a range of percussion instruments at the right tempo has never been easier. There are now plenty of percussion sample CD’s and plug in packages which have great loops and performances on them. Many of these are mapped out across the keyboard in easy to load tempo sets. If you do want to use one of these but do not have access to the audio file, simply bounce it down as a separate audio file and top and tail it. The tempos of the audio files we will use for this process can be approximately the tempo of the song but, seeing as we will be slicing them up in re cycle, this is not of vital importance. However, if there is a big discrepancy you might not get the ideal result. The re-cycle/EXS24 system of building sampler instrument sets creates a lot of potential outside of and away from the particular song you are working on. Once you start to develop a comprehensive library of material then you can have a lot at your fingertips without having to hunt your hard drive for relevant sounds. If you use a lot of your own processed percussion loops as well then you have the benefit of having a unique resource which can only enhance individuality. We have included all the prepared rex files and sampler instruments below and have also included the source audio files so you can try building them from scratch as we do in this tutorial.

Programming, step by step

Download the audio files (800kb)    Download the Re-Cycle files (2000kb) 

Download the EXS24 sampler instruments (3kb)  


Screen shot 1
 The starting point is this long loop of a Brazilian Pandeiro groove that I recorded direct onto the computer without a click. This drum, which is a headed tambourine and the national instrument of Brazil, has a particularly 'lilted' feel. This will be the backbone for our groove.
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Screen shot 2
Here we extract a two bar loop from this selection. I’ve used Sound Forge, although you can use any audio editor. Alternatively, you could select and trim a loop section by using the left and right locators in Re-Cycle. Choose 'crop loop' from the 'process' menu. However, Re-Cycle will not load in samples over a certain number of minutes long so you might need to do this elsewhere if you want to select a section from a long audio file.
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Screen shot 3
Here we have loaded in the trimmed audio file and indicated at the top of the screen that the loop is two bars long. We then clicked on the preview toggle (looks a little like a clock) and this calculated the tempo of our loop. As it stands, the loop has not yet been sliced up so it is still in one piece.
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Screen shot 4
To slice our loop we need to adjust the sensitivity slider to the right. Here we see the slider moved all the way to the right. This is more slicing than we want. You can see on the second wave peak, that the first impact and then the main impact have been identified as individual slices. In actual fact, this is just one sound with the small pre-peak being part of that hit.
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Screen shot 5
We need to move the sensitivity slider back to the right to stop it recognising all of these nuances. This then has the effect of removing some of the slice points we want. Only with really obvious peaks, such as a hi hat part is the slicer intelligent enough to be accurate instantly. It invariably means that you have to check each individual slice with the 'play slice' button and input the slice points with the pencil tool. Zoom in nice and large to do this and audition all the slices. Listen to the end of the slice as well as the beginning. If there is a pop or click at the end you may need to adjust the start point of the next slice. Like anything, there is a knack to this and a little experimentation and persistence will pay off.
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Screen shot 6
Here we see the whole loop trimmed. There is only one pre-peak which needed an extra slice, but most of the rest of the groove is cut up in straight sixteenths.
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Screen shot 7
Save the file in a folder where you keep all your rex files. It is a good idea to have a dedicated folder for these files with sub folders for various instruments. I usually save the approximate tempo in the file name to make future searching a little easier. I have added '80b' which indicates 80 bpm.
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Screen shot 8
This is the Export menu in the drop down options from File at the top of the screen which allows you to export different formats of the Re Cycle file. We do not in this instance need to save the MIDI file separately. The EXS24 sampler will do this for us later.
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Screen shot 9
At this point you can experiment with the Transient shaper, EQ and envelope effects above the sample display window. You can actually get some cool effects with these. Try the silly stomper and the synth chopper in the envelope section or else tighten up a drum sound or boost the bass.
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Screen shot 10
Next we need to load up the EXS24 from our Sampler instruments in Logic. With percussion a lot of people tend to choose mono for each instrument. I prefer to work with stereo, especially if the instruments have been recorded nicely. You can always bounce things down later if you want to ease up some of the strain on the processing power of the computer, depending on how many sampler instruments are running.
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Screen shot 11
We want to import our Rex/Re-cycle file into the EXS24 as a sampler instrument. Enter the EXS edit page and choose ‘extract sequence and create new instrument’
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Screen shot 10
Navigate to where you saved your recently created Re-cycle files and select the one you want. In this instance, we will choose the Pandeiro file.
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Screen shot 12.5
Clicking on your selection will load the individual slices of the Rex file into the EXS24 and then display a velocity factor box. We have chosen a setting of 4. Click OK and then close the edit window and go back to the EXS24 display. If it has closed, re-open it. This will have created the EXS24 instrument and will automatically have saved it in your sampler instruments folder in the Emagic folder on your ‘C’ drive. It will also have added a Re-cycle audio file within the same folder. If it is the first time you have done this then it will automatically create the Re-cycle audio folder as well.
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Screen shot 14
At this point we need to select the newly created instrument from the pull down list. The more instruments you have created then the longer the list will be. It can become unmanageable if you do not go to the root directory and use folders and sub folders.
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Screen shot 15
When selected, the instrument name will appear in green in the central name box on the EXS24.
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Screen shot 16
When you go back to your arrange page you will see the MIDI file of the instrument placed on the relevant EXS24 track starting from whatever point the song position marker was when the instrument was created. It is a good habit to make sure your song position marker is exactly where you want the MIDI file to be when you create the instrument. Otherwise change the start position of the sequence in the event list for objects.
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Screen shot 17
At this point all the notes are there if we enter the edit pages of the midi file. See how Re-cycle has distributed the notes up the keyboard from C1 upwards. Gone are the days of slicing by hand and assigning each note a note number. Can you imagine!! You will remember that the Pandeiro groove had a sixteenth feel. Look at the score and event list. On paper it is anything but regular sixteenth notes. This highlights what we were saying earlier about the feel aspect.
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Screen shot 18
 Let’s copy this to make a longer loop section. Cntrl R opens the ‘repeat objects’ box. At this point we have also changed the tempo to 100bpm. Try experimenting with the tempo. The Pandeiro part will work from anything between 80bpm to 140bpm. There is usually less scope to slow the tempo down with REX sequences because the audio of the slices will not be long enough to fill the time space. However, at a faster tempo this will not be a problem.
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Screen shot 19
If we used this groove with straight quantized material then it would likely clash somewhat. We need to make a groove template of this file to make it our quantize benchmark for everything else. First select the Part by clicking on it, then select ‘Options’, ‘Groove template’ and then ‘Create groove template’
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Screen shot 20
This will create a groove template based on the Pandeiro file. It will be named the same as the file and will appear on the drop down list for the quantize settings. Any of your other sequences in the song can then be quantised with this template.
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Screen shot 21
Here we have gone through the whole Re-cycle/EXS24 instrument-creating process to create a second part for the groove. In this instance it is a simple Cuban Bongo pattern to go with our Brazilian Pandeiro.
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Screen shot 22
Listen to the two parts together without quantizing the Bongos. It’s OK but a bit messy for my ears. We decided to quantize the Bongos too by selecting the Bongo part and then selecting the Pandeiro groove template from the quantize pull-down menu. This quantizes the Bongo part to the template of the Pandeiro part and really makes the groove sit.
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Screen shot 23
Notice how the score of the Bongo part is now very close to that of the Pandiero. One very important point here is that the rhythms need to be similar in the first instance for this to work. If for example the quantize template was based on eighth notes and you tried to quantize a sixteenth note pattern, you would end up with notes being pushed together onto the eighth note meter. Even if there was a fill of sixteenths at one part in the file, you would not be able to quantize that section for the same reason.
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Screen shot 24
We have finally added a shaker EXS24 instrument and selected Control ‘R’ which copies our new additions to the same length as the Pandeiro. The shaker was also quantized before the copy. The quantize setting is automatically applied to any copies. Although we are quantizing everything here, it may not always be necessary and may even be too much in some instances. This is down to personal preference and the invaluable help of your trusty ears.
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Screen shot 25
It is very common to find some percussion sounds that don’t cut through, even though you might have thought they were recorded at a decent level. Here we have added the Gainer from the helper menu to boost it by a few db. Panning can also help it pop out of the mix as mentioned last issue. These are our three percussion voices. It sounds quite full and uncluttered. There is sometimes the misconception that you have to add loads of percussion instruments to make a big sound but is surprising how effective just a few can be. Knowing when to stop is certainly a gift!
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Screen shot 26
You might then want to add a drum groove from a plug-in such as Stylus. Here we have added a loop at the right tempo but it clashes with the quantized material.
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Screen shot 27
There is a simple solution to this problem. Select the new part, solo it and set the locators for a four bar section. (Or whatever length you choose). Go to the mixer page and bounce the solo mix down as a new audio file. Go through the Re-cycle process and make a new EXS24 instrument and sequence from the Re-cycle file. Then quantize this new sequence with your template, delete the old drum part you bounced down from and you should have what you want. This process would obviously work for any appropriate material you wanted to use, even if it’s not at the right tempo. One of the advantages of this whole scheme is that in effect you’re using audio file, but if you change the tempo of the song, everything will change to the new tempo. The other thing worth mentioning is if you want to use an EXS24 instrument that you have already created from a re-cycle file. In this instance, because you are not making the instrument from scratch, when you select the instrument from the drop down list it will not create the MIDI sequence in the arrange windo. To do this you need to select ‘Create sequence from recycle instrument’ from the options menu on the front of the EXS24. This will import the sequence at the song marker point.
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Alternatives

If you don't use Logic and can't use the EXS24 in this way there are alternatives.  The best way to import rex2 files is to use Stylus RMX.  With the use of the sage converter you can import your prepared rex files into stylus and then drag the midi file into the arrangement to achieve the same result, whether you are working in Nuendo, Cubase, Cakewalk, Sonar etc.  There is also a stripped down VST version of the EXS24 for these programs but you do not have the options available to import rex files, only already created EXS24 instruments.  You also cannot create a midi file from the rex file in this version.

Pandeiro, Brazil's national drum

Pandeiro is the national instrument of Brazil and is a single headed tambourine traditionally made with stretched animal skin parchment. Modern drums often have plastic heads, which provide a slightly brighter tone. The drum is usually tuned high and is played with the thumb, fingertips and wrist of the right hand whilst the left hand shakes and adjusts the pitch with a finger inside the drum. Pandeiros are an integral part of Brazilian music and the craft of the instrument is taken very seriously all over the country. One of the attractions to the instrument is the juggling tradition and there are even national competitions for Pandeiro juggling in Brazil.

The actual articulation of the strokes on the drum is quite a tricky technique and gives it its distinct Brazilian feel. Thumb-Fingers-Heel-Fingers is the basic flowing sixteenth pattern of the right hand with the left hand muting on the first and third beats of the bar and un-muting on beats two and four to create a deep open tone. It is actually the reverse of a ‘Kick-Snare’ feel that we are so familiar with. The rhythm used for this article is slightly more involved than this though. Even though the instrument is so popular in Brazil, it is less frequently used in carnival because it is not loud enough to have a big impact for out door events.

 

   

 


 

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