Richard D. James, better known as Aphex Twin, an artists whose musical output is unparalleled in its almost obnoxious attitude, coupled with being truly beautiful, at moments humorous, other worldly and of a technical level oh-so-many producers aspire to grasp at. Pretentious kiss-ass intro over, Aphex Twin is still one of the most influential electronic artists there has ever been.

Perhaps better known for his scatty hyper active cuts like Flim or 4 or his sideways glance at hip hop music videos Windowlicker, James was churching out acid techno, jungle-like numbers and even ambient music long before the semi-coffee table success of the 2001 double album Drukqs.

It’s actually his ambient output I want to take a quick look at, in particular the lead track from his Selected Ambient Works 85-92 (released February ’92), Xtal. As with most of his music, he ascribes are barely legible consonant riddles name to it, so whilst I don’t know how it’s pronounced, most agree on ‘tal’ or possibly ‘crystal‘.

*edit 2018* It almost certainly refers to this crystal oscillator. Thanks EEVblog.

I have to say, despite individual sounds not being that difficult to emulate, the overall mix and balance of this was a nightmare, due to (in-part) Aphex Twin’s notorious ambiguity around customised equipment and largely down to the poor sonic quality of this track.

SAW 85-92 is claimed to have been digitised from home cassette tape, and whilst I am a big fan of this medium (out of nostalgia, not choice), it’s given so much midrange crunch to the mix, it was near impossible to accurately discern certain sounds. So with that in mind, this replay is an attempt at getting the vibe down, rather than an exact carbon copy. Let’s get cracking…

Drums

First thing’s first, let’s set our tempo to 114 bpm. The track starts with some 808-like hi-hats, so it seems only natural to start off with the drums. Although the drums are 808 in style they are likely to be from another Roland drum machine, the R-8. This had its own rudimentary sounds in it but in addition you could expand it with cards from other drum machines, such as the aforementioned 808 and another Roland classic the TR-909.

Live has some decent 808 sounds that come pre-packaged with the Drum Rack sampler, but I opted for some of my own. Adding the necessary hits to a new Drum Rack (kick, snare, open and closed hats, maraca and cymbal) I’ve tuned and processed them to try and match the original sound more closely.

Let’s start off with the kick drum. To add some extra bottom-end to this I layered it with an Operator instrument tuned to 52 Hz, adding Live’s Compressor and the Dynamic Tube using a tweaked Distortion Gate preset. The snare was fairly unremarkable, just using some pitch enveloping and an EQ to boost around 198 Hz.

I grouped the closed and open hi-hats together so they could share some processing. I’ve added Live’s Reverb with a healthy 2 seconds of Decay and an instance of TB Ferox. This is a tape simulator plug-in that has some handy features for dirty-ing up these hats. I’ve employed some low and high cut, added some compression, saturation and tape delay, giving it a warbling quality.

Lastly there some maracas and cymbal, both fairly light on the processing with just a simple delay on the maracas (30 ms for the left channel and 75 ms for the right) and some reverb for cymbal.

All of the drums are routed into a Redux at 16 bit with a Downsample of 2. This helps age the samples a bit and add some grit. I’ve then added some compression and used a send-return for some extra reverb. I’ve opted for the free Voxengo OldSkoolVerb, as this sounds the closest to those early ’90s reverb units.

N.B There is some extra processing on these tracks, which I’ll come to later (see Tape it or Leave it).

There’s another drum loop that enters around the 59 second mark, this is a breakbeat sampled from Tommy Roe’s 1966 Sweet Pea (you can grab a wav of the loop here).

I’ve loaded the wav into Live and turned the warp off. I’ve then tuned it down a few semitones to more closely match our tempo. Now consolidate the file (cmd + j) and add the resulting loop to a Sampler instrument. I’ve then made four chops of the sample, the first kick, both snares and a little shuffle.

Program the loop like so. The second snare is off-beat, on the one four and the four-and (confusingly!).

Not much processing here, I’ve added some compression to toughen it up a bit (long attack short release, medium-to-high ratio, low threshold) and send it out to our same reverb return track.

*edit* Both WhoSampled and WATMM user EKT Plus have pointed out that there might be an Apache break in there, which is entirely possible. Some bongo-like sounds can be heard, so it could be layered or used exclusively.

Chords

There are two main chord progressions in Xtal, the main one that starts the track and the second that enters at 1.49. I found this handy Reddit on AFX MIDI files, and although Xtal was here and it helped me get to the bottom of the first sequence, I found myself tweaking it a little.

The main progression is loosely based around G minor 7, Eb major 7 and a sort of F6 chord (if you’re not familiar with chord naming conventions have a read of this).

The second progression is a simple three chord loop, Bb, something like Bbsus chord and Bb second inversion:

Here’s a nice acoustic cover from YouTuber coverwwz90 さんのチャンネル that breaks down the harmonies a bit making them easier to detect:

Synth Sounds

Once the chords were down I needed to give them a synth patch. This is the part of the replay I struggled with the most; the mix is so drenched in reverb and tape saturation it was hard to hear individual timbres clearly.

This Reddit on Xtal’s synths helped a little but without knowing exactly what synth and processing was used it’s all guess work really.

There are three main synths I can hear, the synth that plays the first chord progression, a little 16th note riff and the synth the plays the second chord progression.

Let’s start off with the first synth(s). Many sources claiming this to be either a Yamaha DX100 or perhaps a Roland Alpha Juno likely running into an Alesis Quadraverb, although it’s likely we’ll never really know.

I trialled various subtractive synth combinations with my Korg Wavestation but eventually decided to layer an FM synth and some sort of 90s ROMpler, the thinking being most of the body of the sound could be covered by FM and the ROMpler could add some vocal pads or similar.

I used Native Instruments FM8 using three operators. D and F, panned to opposite sides of the stereo spectrum, were both marginally detuned sine waves. E was another detuned sine modulating the frequency of itself and the other two, I adjusted the envelope to try and add some movement to this. In the master section I’ve added some unison detune and spread, also adding some Analog and Digital quality. Lastly in the FX section I’ve added some Tremolo, Reverb, PsycheDelay and Chorus/Delay to butter it up. It’s okay but not perfect (you can download the patch here):

To layer this I firstly grouped the FM8 synth into an Instrument Effects Rack (cmd + g) and added the excellent (free) UVI Workstation. I loaded a copy of Digital Synsations, a bundle with samples from the Yamaha SY77, Korg M1, Roland D50 and Ensoniq VFX.

I used a tweaked version of the Synth Glass Vox patch found in the D590s portion of the library. This is based on the D50, which used a technique called S&S (sample and synthesis) to emulate sounds. Removing all of the FX and adjusting the amplitude envelope to taste, I also added Live’s Auto Filter to aggressively high-pass out the bottom end (and most of the mids) at 760 Hz.

Adding both of these layers together, I added some compression and (probably my favourite reverb) Valhalla Shimmer. This nicely emulates the Quadraverb and you can even dig out forum posts from their developer Sean talking about their similarities and even people posting about SAW Vol. II in that same thread.

In this same section we have the 16th note riff I mentioned above, here’s the MIDI:

For this is used UVI Workstation again, exploiting their multi-part layering within the sampler. For the first part I used the Vox Planet 1 preset found in the DS1 library (Korg M1) and for the second part I used Massy Christmas found in the DS77 library (Yamaha SY77).

I ran these into some filters to box the sound in, the retro sounding SoundToys Little PrimalTap delay and another instance of Shimmer.

Individually each of these sounds doesn’t stack up, but together they go someway towards sounding a bit like Xtal (DISCLAIMER AFX GROUPIES: THIS IS NOT GOING TO SOUND AS CLOSE TO XTAL AS YOU WOULD HOPE) I’ve left the reverb tail in so you can appreciate it.

The second pad that comes in at 1.49 is a little easier to approximate. I’ve used FM8 again, tweaking an old Eno preset called Glide (you can get the SysEx files here). I’ve added some low-pass filter envelope modulation from Live’s Auto Filter, Shimmer and some compression.

Again it’s not perfect but it’s a foot in the door.

Sample

The vocal sample that characterises this song is actually from a 1986 library music release, which can be found here on Discogs. It’s pretty hard to find a digital copy, and no one who had this upload on SoundCloud was willing to share, to I just ripped the audio from the below YouTube clip. Not something I’d recommend but needs must.

Obviously it’s poor YouTube quality compression meant I wasn’t going to get the cleanest rip, it was plastered with vinyl crackle and the recording was actually clipped a little but I sort of convinced myself that this was no bad thing and added to some of the lofi qualities.

I’ve loaded the wav in and added it to a sampler, tuned it down 50 cents and chopped the relevant vocal snippets on to different keys, programming the below loop:

I have to confess this took about three attempts, with me constantly going back and checking my work against the original to make sure I’ve taken the right bit, and I’m still not totally convinced, but it’s close enough.

To try and clean it up I used two Waves plug-ins, the X-Crackle and X-Click. I found them both very intuitive and got half decent results quite quickly. James was known for using the Casio FZ1 sampler around this time, so I added Live’s Redux to simulate the low sample rate this machine had. I then EQd out the bottom and top end a little, added some compression, some Little PrimalTap and Live’s Reverb.

Bass

The booming bass that enters with the breakbeat drums, and is a resampled 808 bass drum. Firstly I tried the main one I’d used from the drum machine, but I needed a bit more bottom end, so I added one made from an SH-101 from an Urban Shakedown [sorry don’t know where to get this anymore!] sample pack. It was mono and a low bit depth and sample rate, which also added some nice artefacts. I just added some EQ to remove any sub sonic frequencies.

Arrangment

Most all of the tracks have had some degree of reverb added to them to add to the space-y quality of the track. I added some bit and sample rate reduction from Redux to the reverb and low-pass it a little bit, just to make it sound extra grotty.

Apart form fading in the main synth parts in the intro (I used a Gain plug-in rather than the volume automation – long story) there’s no other automation going on that I can hear. There’s probably some messing with the send/return values and odd bits of filtering, but nothing drastic.

Here’s the whole arrangement. Click on it to view it larger:

Tape it or Leave it

We’ve already mentioned how much tape saturation and warble is on this mix, so naturally my first consideration was to add some TB ReelBus to each track. This adds a tonne of tape hiss and asperity noise (don’t know what that is, not gonna lie) so watch out and check how it sounds at louder volume so you’re not destroying the mix.

It’s more prominent on some tacks than others, for example the drums, vocal sample and master, it went some way towards dirty-ing up the mix.

However this wasn’t enough degradation, so I added an Audio Effects Rack designed by Dutch producer Legowelt, which is free on his website (head over to the software tab on the left).

This uses combinations of Live’s native effects such as filters, vinyl simulators, compressors, flangers, frequency shifters and more to emulate the sound of tape, with some handy tweakable macros.

You can hear it in action here:

I added an instance this to each track tweaking various parameters depending on the instrument, for example I could get away with more Pitch Wobble on the vocal sample and pads than on the bass, and I could add more Tape Phat and Bias to the drums and bass.

I also added an instance to my master channel strip along with another TB ReelBus and a Focusrite Scarlett EQ to further dull some higher frequencies and add a little warmth to the low-mids.

That’s it! Musically this wasn’t a difficult track to approach, but sonically it threw up a whole bunch of issues firstly because Aphex Twin is both a fantastic producer but also one who keeps his cards close to his chest and secondly because of the well documented issues with converting from home cassette tape.

Here’s the finished track. There’s a lot about this which is educated guess work and some is just pure guess work, so do bare that in mind before sending me any hate mail, but I would certainly be interested in any comments.You can download the Ableton project here. Enjoy!