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Vintage Synthesis on theAWE32

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(Soundfont Format 1)

What is Vintage Synthesis?

Before I answer this, you're probably wondering why anyone would want to emulate vintage synths on the AWE32 when you could easily sample them! The answer is simply RAM. R-A-M. RAM!! Downloading several megs of samples to your AWE32 can be a daunting task, and sometimes the sonic results aren't as good as the size of the Soundfont would suggest! I've often downloaded huge Soundfonts off the Internet only to find that they're utter crap! This isn't funny when the files are Meg sizes!!! Besides requiring huge amounts of RAM to get an accurate representation of a vintage sound (try loooong filtered sounds - Bye-bye memory!), where do you get these sounds cheaply and easily? On the internet? Nah, not really! Those that are there are usually sub-standard (although not always) and low sampling rates are frequently used. I once saw a Linn 9000 sampled at 22Khz!! The result was a bunch of samples which didn't bare much resemblance to the original sounds. Even sample-cd's don't cover every vintage sound you've dreamed of, so you have to buy several of them. This can of course set you back the price of buying an actual vintage synth in the first place!? Another flaw in these sample-CDs is the fact that several of the waveforms are sampled from samplers ... knowaddimean!? You end up inheriting all the inadequacies of the original loop-points ... etc ... etc. Not a pretty site at all! What is the solution then? I studied up on vintage synths to find out how they think and operate. Then I ported this knowledge across to the AWE32 in an attempt to penny-pinch by emulating these synths. Here's the story ...

Vintage Synthesis can best be described as emanating from synthesizers which many people regard as outdated, but which still provide a wealth of sounds usually bearing little resemblance to realistic sounds. They are usually based on some mathematical and electronic circuit principles which don't rely on sampling (usually) or software for their sound-generation. This is essentially what makes them so unique and varied, and so sought after. However contradictory this may seem, it is for this very same reason that some of their sounds have become cliche and overused. This can of course be attributed somewhat to sampling itself - People just can't get enough of vintage sounds so many have been sampled to death. Samplers seem lost without analogue sounds from Roland's TR808 and TR909 drum-machines - A bit strange for equipment which should be technically and sonically far more advanced??!

Who could forget the Yamaha DX7 electric pianos? What about that Roland TR808 cowbell, or the thumping TR909 kick drum? No self-respecting dance muso would be found dead without some of these sounds in their arsenal (or at least samples of these sounds!!) Instead of sampling vintage synths, wasting time and RAM, why not just buy one of them? The reason is simple - They're a total rip-off!! Their prices have been blown way out of proportion by the huge demand for new (old??) sounds. Fortunately some manufacturers have picked up on this - Novation in particular with their Drumstation and Basstation, and Roland with their new MC-303 - and are offering vintage sounds at comparable and sometimes lower prices. Make no mistake, I looooove vintage sounds, but the sampling era has helped push some of them to monotonous oblivion. A new approach to sampling these beasts is to emulate them on a sampler or wavetable synth like the AWE32. The severe complexity involved in this process alone should at least rid us of many of the cliched sounds, not to mention inventing some surprisingly new ones. Right, on with the task at hand ...

The Architecture of a Vintage Synth.

Firstly, to understand exactly how to emulate vintage synthesisers on your AWE32, we need to take a look at the architecture of vintage synthesisers. How do they generate their sounds and how are these sounds processed before reaching their final output? The answer to these questions should provide a fair idea of the basic building blocks required for emulating vintage synths on the AWE32. Now before you take the following paragraphs as gospel truth about vintage synths, let me explain that I have had an extremely low amount of exposure to "real" analogue synths. In fact, the only analogue babe I ever played around with was the Yamaha CS5, so there! I am however reasonably knowledgable in electronics and computing, and I'm quite learned (as far as reading material is concerned) concerning the workings of vintage synths. So, expect an error here or there, but by all means give me a shout if you disagree with anything I say.

Firstly, every synthesiser must have at least one oscillator. An oscillator in the simple sense is a wave-generator, or the initial sound-generator if you like. When you pluck a guitar string, the vibrations (oscillations) of the string produce a sound. So too does a synthesiser produce oscillations, albeit a lot more simple than those of a guitar string. Whether these oscillations are generated by analogue circuitry, mathematical principles or the physical plucking of a guitar string is immaterial - They are all oscillators. Obviously the more oscillators available, the more creative potential you have at hand. Luckily the AWE32 allows you to layer sounds and process them individually, giving you several potential oscillators to work with. Exactly how many are available I don't know, but I haven't yet reached the AWE32's limit!

Secondly, the oscillator must be passed through a filter with a cutoff frequency. This changes the colour of the initial sound by removing and accentuating certain frequencies present in the oscillated source - A bit like the way the shape of your mouth changes an "eeeeee" to an "oooooo". This is a major part of analogue synthesis, and the AWE32 has a pretty good filter to work with.

Thirdly, this filter can be controlled by a Filter Envelope Generator. This means that the intensity of the filter can be set to vary according to a specific pattern over time (ADSR Envelope). This allows certain frequencies to be dulled and accentuated at different levels over time. The AWE32 has this feature too, but unfortunately this ADSR (see explanation later) envelope is shared by both the pitch and filter of the AWE32 - you can only assign the envelope to one or the other, but not both. What a pity!

Fourthly, the resulting sound must then be passed through an Amplitude Envelope Generator, which signifies how the volume of the sound should change over time. This determines whether your synth sounds like a flute or a piano! How fast does the sound reach it's maximum volume (Attack)? How slowly does this volume fade away after releasing the key (Release)? This is most commonly referred to as the ADSR of a synth - Attack, Decay, Sustain and Release. Obviously this feature is also on the AWE32 otherwise it would sound like an organ!

Low Frequency Oscillators (LFOs) are then applied to the volume to create tremolo effects, or to the frequency to create vibrato effects, and also to filter properties ("Wah-Wah") of the resulting sound. The AWE32 has 2 LFOs : One reserved for vibrato, tremolo and wah-wah ; the other for vibrato only. Both can be programmed to kick in after a specified time (delay), which is quite a useful feature also found in most other synths. An LFO is basically the same as any other oscillator, except that it has an extremely low frequency which is inaudible as a sound to the human ear. The LFO effect can however be heard as a change in the sound. Unfortunately the AWE32 (well, the Vienna software at least!) only provides a sinewave LFO. The addition of others (Random, sawtooth ... etc) will hopefully be implemented in Soundfont 2. This will make the quest for AWE32 analogue synthesis even more productive and creative.

Oscillators - The Beginning of a Sound

As stated earlier, every synth must have at least one oscillator. This oscillator is usually capable of generating several different types of waveforms. The most common and easiest vintage waveforms to emulate for use on your AWE32 are the following :

Sine                  Triangle          Square          Sawtooth           Pulse-Width               Whitenoise

A Sine wave is very smooth in character, and ultimately has very little creative potential when passed through a filter. This is due to the fact that a filter actually smoothes any wave in the direction of a sine wave. eg. A filter can smoothe the squareness of a square wave so that it begins to emit the characteristic smooth sound of a sine wave. The transformation is not exactly from square to sine wave, but the similarity between a filtered square wave and a sine wave is definitely noticible. Consequently a sine wave has a more limited use than other waveforms in synthesis. It can however be used for very low, throbbing bass sounds and analogue percussion sounds like kick, and tom drums.

A Triangle wave is slightly brighter than a sine wave, and is a little more susceptable to a filter. It can be used for flutey sounds, very synthetic "cheap-synth" sounds, and also extremely harsh, thumping bass drums, like those generated by the TR909. Remember the Casio VL1 VL-Tone keyboard? This is primarily the main source of it's sounds, as well as the square wave. El-cheapo, here we come!!

The Square wave is extremely bright, almost to the point of being quite harsh. It can be used for very bright flutey sounds, and is perfect for synth-pop sounds. This is a great waveform for emulating Yazooish (can I say this?!) sounds, as well as Depeche Mode sounds from their Speak and Spell era. When filtered it can fit right up there in the mix with real retro synths.

The Sawtooth is the crux of vintage synths. It can be harsh and grinding in it's raw form, and used hand-in-hand with filters this is the epitomy of retro-pop. It can be used for synth-bass and various string sounds, and for those sounds that I like to call the ZZZZZ sounds - Roland MC202 bliss! Especially for those TB303 lovers out there, this is where the AWE32 can become your resident TB303 master - Heavely filtered sawtooth sounds on the AWE32 are TB303 heaven!

The Pulse-width waveform is a modified Square wave and it doesn't vary much therefrom. It's sound is easily identifiable though because it has a square-wave sound with a more grungy edge to it. Generally it is a square wave with the width of the pulses altered in some way, causing a characteristic change in sound. It is often used as an alternative to the Square wave because it is variable and provides more interesting basic sounds, especially when filtering is used. I honestly haven't paid much attention to this waveform because in my experience on the AWE32 it doesn't offer anything special in terms of a being a different waveform.

Whitenoise is a high-frequency random waveform. There is no structure at all to the waveform, except to say that it is a series of random pulses. In it's simplest form it sounds like the hiss of a radio which is not tuned into a station properly. There are different colours of whitenoise which can be generated, like pink or brown noise. The reason why we use the term colours as opposed to pitch is because whitenoise, being random pulses, doesn't really have a pitched waveform. It can however be altered quite easily using a filter. Whitenoise is used mainly in soundfx, as well as percussion instruments requiring noise (snares, hi-hats ... etc).

By combining these oscillators together, as well as the filters, envelope generators (EG) and LFO's on the AWE32, quite complex sounds can be generated. Since the AWE32 has all the aspects of a vintage synth, all we need do is create the basic waveforms as shown in the diagram above, and then process them through the AWE32. A simple way of doing this is to use Cool Edit to produce the waveforms, and then once we have these waveforms, the AWE32 has the power to perform many of the other functions which vintage synths are famous for.

Creating the Waveforms

The easiest way to create these waveforms is as I said before, to use Cool Edit. It generates all the above waveforms, except the Pulse-Width waveform. I won't go into detail as to how to create specific synth sounds, except to say that you should as far as possible try and limit your waveforms to a 1½ to 2 wavelength size (the diagram above shows single wavelengths). This way you can loop the waveform and it will, despite its tiny size, give you an accurate representation of the original sound. This means you can cut your SBK down to a fraction of the size you would normally encounter with sampling, but still have a workable sound. The whitenoise is usually the only exception to the 1½ - 2 length waveform because of its random quality. You will have to determine the optimum loop length of a whitenoise waveform yourself.

Although synth sounds are relatively simple to create, percussion sounds are an absolute nightmare to synthesize. The basis for vintage percussion on the AWE32 is a Sine Wave and Whitenoise. With these waveforms you can generally create a whole TR808 drum machine. Let me start with a discussion of what constitutes the basic structure of the main percussion sounds :

1) Bass/Kick and Tom Drums The first sound emanating from a bass drum is the noise created by the pad hitting the surface of the drum, creating a loud, very short click. This is followed by the fading "hum" of the resonating drum cone. This hum goes from it's original pitch to a slightly lower pitch, although due to the very low frequency and the shortness of the sound this is often not consciously heard. The reason for the pitch change is very simple ... When you first strike the drum, the skin of the drum is initially tight but fades back to a lower taughtness after being hit. This causes a drop in frequency because the tighter skin has a slightly higher pitch, which lowers as the drum skin returns to it's original taughtness. Depending on the makeup of the bass drum, this effect may vary considerably, but it is generally not very noticible on a kick drum. Thus there are 3 qualities needed (the first two being all important) : a) The initial click as the pad hits the skin. b) The fading resonating boom after being hit. c) The lowering pitch. a) and b) can be created in one go using a sine wave: Generate a sine wave at about 70-100 Hz. Clip it so that it starts at a maximum waveform value (as far away as possible from the zero mid-line). Then mark a micro-minute portion right at the start of the waveform and invert it. This will give you the initial click, and when looped beyond this click the looping sine wave will also give you the resonating drum boom sound. An example of the waveform is shown below :

                                                        

Analogue Sine Bass Drum with Click ^ This is the click

You can also just layer a very quick decaying whitenoise wave to form the initial click rather than altering the Sinewave as in above, but for TR sounds this doesn't work well. The decreasing pitch can be obtained using the AWE32's pitch ADSR after the waveform has been successfully looped. Use a quick lowering of the pitch with the ADSR to create the right sound.

2) Tom Drums The Tom drum has the same format as the bass drum except that the pitch is higher. Also it is here that the pitch change becomes more noticible. This is because the decay of a Tom drum is usually longer than that of a bass drum, and the starting pitch is also a bit higher. The drop in frequency thus becomes more noticible. An additional feature to the Tom scenario is to layer a very short whitenoise wave at the start of the Tom, at a relatively low volume. Depending on how you filter and pitch this whitenoise, you can give the Toms a bit of a grungy sound rather than the usual clean boom sound.

3) Snare Drums For this you need whitenoise and a kick drum (as above). A Snare is similar to a bass drum, with the major difference being the noise generated by the springs attached to the underside of the drum skin. Generally, use the above bass drum at a higher frequency (since a snare drum is smaller than a bass drum) layered with a looped whitenoise waveform decaying as desired. This is the basic building block of your snare drum. You can filter the whitenoise to a desired colour, and also layer more whitenoise at different frequencies to vary the sound. I have found that higher frequencies (colours?!) of whitenoise are the best for snappy snares like those of the TR808 and TR909. You can create a whitenoise wave in Cool Edit, and then filter it with the quick filter, pushing up the high frequencies and excluding the lower ones. This generally gives the most impressive high-frequency whitenoise waveforms rather than using the AWE32's filter. Be careful not to over-filter the whitenoise because this makes your snares sound puny, which is aweful unless you're looking for a very '70s Casio or Yamaha mini-pops. Also, adding a bit of reverb to the snares can be quite effective, although the same doesn't apply to chorus - it makes the snare sound very awkward.

4) Hats and Cymbals For the hats, use heavely filtered whitenoise layered with an ultra-high frequency sine, square or triangle wave. The volumes of the whitenoise and high-frequency wave will have to be jiggled a bit, but generally the hats sound better with the filtered whitenoise louder than the high-frequency wave. If possible, use Cool Edit's Quick Filter to boost the highest frequency and remove all other frequencies in the whitenoise wave. The need for AWE32's filter may not even be necessary if you use this method. In fact, sometimes heavely filtered whitenoise doesn't need another hi-frequency tonal wave layered alongside to make the hat sound convincing. The cymbals are similar, except I find it better to use more than one high-frequency wave and detune them. This improves the noisy quality (as opposed to the hissy quality) of the cymbal. Also, you can layer a slightly lower frequency whitenoise waveform with a very short decay to imitate the actual striking of the cymbal.

General Vintage Considerations

When attempting to emulate vintage synths, it is important to note that there are several ways of creating convincing clones. Some have already been mentioned, but here is a more detailed list :

1) Chorus There are two types of chorus which are most prevalent in modern synths and samplers. One takes copies of the original sound and plays them out-of-phase. This produces a richer and more evolving sound, which analogue synths are often characterised by. You can simulate this on the AWE32 by layering two identical sounds into one patch. The other method takes copies of the original sound and outputs them at a slightly different pitch. This produces an effect which is essentially identical to the first method. Technically they are very different, but the effect on our ears is often too similar to be noticed. I'm not sure which method the AWE32 uses, but in any event it is an integral part of emulating vintage synths. My advice is to use lots of chorus on synth sounds, but hold back on the percussion sounds. Using chorus is an easy and effective way of getting that unstable quality which analogue synths are renowned for, and the AWE32 has this in abundance. If vintage synths were human, chorus would be the creativity.

2) Detuning Ahhh, this is where we reach an important, often overlooked part of analogue synthesis! Many vintage synths have more than 1 oscillator per sound. Output these at slightly different pitches and they simulate a chorus effect. Fortunately further detuning allows wide variations in the pitches of these oscillators, and this can go way beyond a chorus effect. If you're looking for acid licks then this is your baby! The AWE32 allows you to layer many oscillators, so the effect of detuning these can become monstrous at times! The method I frequently use is to layer 2 or more identical oscillators in an instrument. Use similar ADSR, filter and LFO properties for each of these oscillators. When I say similar, use slightly different rates of attack and decay of filters, LFO speeds and values ... etc. This will create a more evolving sound, almost to the point of being ever-changing - an analogue necessity! Then use the AWE32's fine tune to detune some of these away from the base pitch. When the goosebumps settle after hearing this effect at work, you'll know that you've got what you wanted! If you don't detune enough then the effect won't be more than a chorus. Of course using both detuning and chorus will bring tears to your eyes, mark my words! You can of course utilise waveforms panned left and right as well to give you that ever-changing sound. Detuning gives aggressiveness to your sounds.

3) Filters You're not going to get very far in your vintage quest without this, believe me. Use it often and use it abundantly whenever possible. If oscillators are the voice of an analogue synth, then this is the mouth through which it speaks!

4) LFO's Here's another vintage necessity which must be used in abundance for strange and off-the-wall sound-effects. Subtle use is of course necessary too, and it gives character and life to the sounds. LFO's are the heart of vintage synths, giving the sounds an animated feel.

Other Bits of Info

For your convenience I have already created several basic waveforms. They are all 16-bit samples generated at 32Khz and 44.1Khz, so although not CD-quality you will be hardpressed to tell much of a difference (know any analogue synths that are CD-quality!?) The available waves are: * Sine Wave * Square/Pulse Wave * Sawtooth/Ramp Wave * Triangle Wave * Whitenoise Wave * Modulated Waveforms (FM) * Additive Waveforms

The 16-bit Additive, FM and Modulated waveforms were generated at 32Khz using one of my own programs. The reason why they are only 32Khz waves is so that they can span the whole keyboard using just a single waveform rather than multisamples - 44.1 kHz doesn't allow this with as much accuracy. I'm using a PC200II keyboard, so everything is based on this. Also, the highly unplanned, undocumented, unstructured and erratic program I developed to generate FM waveforms makes different pitches of the same waveform very difficult!! Anyway, it works (mostly?!) and these waves are the proof. One thing I've discovered is that these waveforms seem to be a lot easier to loop than those generated at 44.1 Khz. I'm not exactly sure why this is so, but after editing hundreds of waveforms (millions!!) I discovered that I had more trouble looping 44.1 kHz waveforms than I did with the 32 kHz waves! Strange, but true! Each wave has been normalised and optimised in Cool Edit, so they're ready to roll.

If you need any other examples, try out my VINTAGE (Vintage Dreams Soundfont), VD808 (Vintage Dreams 808 - TR808), VD909 (Vintage Dreams 909 - TR909) and VDCR78 (Vintage Dreams CR78) Soundfonts. They contain many, many examples of layered sounds using all the abovementioned principles. There is also a new VD101 (Vintage Dreams 101 - TR101 !?) Soundfont which I did. It is basically an undiscovered Roland TR machine (Ha! Ha!) which I felt like doing. I am currently working on VD303 (Vintage Dreams 303 - TB303) and VDFM (Vintage Dreams FM) Soundfonts, which should be finished in the next few weeks. Use these Soundfonts as examples and pretty soon you should be shovelling out several new vintage soundfonts with your very own personalised flavour.

Where Did This all Come From?

It all started back in about 1980 when I played with a Casio home keyboard in a department store. I was amazed at the sounds coming out of it, even though by today's standards they would be classified as cheesy. I was hooked on anything and everything electronic after that. My music tastes narrowed towards groups like The Human League, Depeche Mode, Yazoo, Thompson Twins, Duran Duran, OMD, Erasure and Kraftwerk, and my quest for an electronic synth became almost demonic (I was only about 12 then!?). Don't worry though, my musical life doesn't only consist of electronic stuff - it just seems that way!

Finally I got my first real "workstation" (Ha! Ha!) which was a Casio SK200. I did some wierd and wonderful songs on that keyboard, even without MIDI! Then I got a Yamaha PSS680 - not much better, but at least it had MIDI! Still I wanted more because samplers had become a big thing, and my fave band (Depeche) used them so I just had to have one! I got a Roland SC55II to fulfill my need for "real" sampled sounds, and a Yamaha TX81Z for my FM needs, and then I got my AWE32. It was here that I realised that all these fancy sampled sounds were missing something important - character! I then got myself a Roland D50 which, although it had awesome sounds, could still not get those early '80s sounds without too much programming. I couldn't find all those juicy sounds that The Human League had used in Dare (although my first synth was the Casio VL1 they used!), and those cheap sounds from Depeche Mode's Speak and Spell album were nowhere to be seen. What about Vince's noises from Yazoo?! I was a frustrated musician!! Then I decided to use my AWE32 to emulate these sounds. What a great idea that was! So far the quest has been quite successful and I have been able to clone many of those early '80s sounds. After all, that was what my quest was all about - cloning '80s synth sounds. Now I've achieved it, so what next ...

If you have any queries, comments or criticisms, please send me eMail with all your suggestions. If for some reason you can't get hold of my eMail address (they keep fiddling with it!!!) then try Robin Edwards' great web page called Virtualog32 at www.gold.net/clockworx/virtualog32. It is a Net group-project dealing with the creation of analogue sounds on the AWE32 - Something which has long been overdue! Unfortunately Robin has been having space problems so it has been neglected, but it should be back soon. Also, Todd Eaton has a great page at www.infinet.com/~teaton/awe32/awe32.html. He is endeavouring to up the availability of AWE32 stuff, and it looks to be quite a hot site. Check them out!

Soon I'll be getting my much awaited Alesis QS6, so all this work will be transferred to the QS6, and from there on I think my AWE32 output is going to be very minimal.

Hope you get some use out of this package ...

Ian Wilson

eMail : Durban1@IscorLtd.co.za Snail Mail : 16 Carmichael Place Woodlands Durban 4001 Republic of South Africa


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