Tracking and Demoscene discussion.

Realistic Guitar Tracking: A Pesonal History

Realistic Guitar Tracking: A Pesonal History

Postby FingerSoup » Tue Mar 16, 2010 4:59 pm

By: FingerSoup

An Introduction to the Author

I have been tracking off-and-on since about 1996, and predominantly been doing stuff with guitar. I'm writing this history to hopefully share my thoughts and reasons behind my guitar tracking, so that others can learn from my experience.

I originally got into tracking because I wanted a backing track to play to, so i could learn guitar better. I would transcribe songs from sheet music into the tracker. Of course, this was in the days of DOS, where hard Drives couldn't handle multi-track recording in any capacity, so you needed to assemble your music on a computer, and in the MIDI/MOD war, I liked the sound of MODs...

After I got good enough on both guitar and Impulse Tracker, I started writing music for myself on the guitar. I also began writing my guitar ideas directly into trackers, while I composed, to keep a record of what I played.

I've released a really small amount of music. Partially because I have about 40 incomplete ideas that I've given up on, but partially, because the sound hadn't been right for a long time. It always sounded too cheezy, and never sounded "Real". So, over the past 10 years, I have been trying to make tracked guitar sound a little more like it isn't tracked.

First, I should identify what I didn't like about tracked guitars. Most oldschool tracked guitars had either unnattural sustain (either too long or too short), Distortion dynamics changed from note to note, giving a hollow sound. Strums had too much attack. Single notes often didn't have enough. Guitar leads were written like pad synth leads... Everyone who tracked guitar aimed for Metal. Metal was the only semi-convincing tracked guitar at the time, because the distortion in metal was so heavy it sounded semi-electronic at times. I didn't want to do Metal.. I wanted to do Classic and Alternative Rock, with a little punk thrown in.

The few MODs that were up my alley were the first ones I deconstructed. Most of these were actually short clips and loops of live played guitar. it was stuff that was hard to time without a metronome or backing track. Thus, I started my quest for true realistic sounding guitar, on an individual note basis in tracking.

Step 1: Figure out what veryone else was doing

Nobody goes out to make a bad sounding guitar, especially when it is the feature instrument of their song. If I could understand WHY they made their samples sound the way they did, then perhaps I should learn from them.

First, I was already familiar with Sample rate distortion. The faster I play a sample, the shorter it is, and the higher the pitch. Technically, this is how guitars and other instruments change their notes. Shorter strings means faster vibrations, thus higher pitch. The one thing that isn't taken into account on a computer though, is the environment. On a guitar, the friction that air puts on a string while it's virbating is constant, while the string lenth isn't. On a tracker, the two become linked. As a result, the subtle properties of the guitar string are lost. This becomes even more disctinct when other effects are added. Distortion and overdirve on guitar, is technically little more than over-amplification. Thus when these subtleties, along with Tube hum, vibrato and tremolo are all mixed into one note, the unheard flaws become highlighted in the sped up tracked note. Minor pitch changes caused almost a phasing or a doppler-like effect, causing the hollowness in the metal Chords. This explained why Guitar tracking was becoming more and more multisampled. ITI and XI instruments were key. The more volume balanced samples the better.

This also explained the uniformity of samples. in an effort to reduce the number and size of samples, most samples had loops built into them. Basically, because of the variances in a single note recorded, often times, people would trim the sample short, then loop it early on, and for a short amount. The sample then would use note-off envelopes to end notes.
Then there was the lack of attack. As I experimented with sampling, I noticed that when I used one sample for an entire song, Chords sounded unnatural. this was because when I played 3 notes all at once, the highest note plucked itself first. Multisampling fixed this to a reasonably unnoticeable level, but it also explained why in classic MODs, these samples didn't just trim to the beginning of a pluck, it trimmed the pluck right out. Again, this was an excuse to reuse samples to save space. This sometimes gave an unnatural start to a sample. I now understood why people were fading notes in and using guitar samples like pads or strings. It got rid of the nasty abrupt midway start of the note.

Step 2: Figure out what happens on a real guitar

So I finally understood that the concessions made by previous guitar Trackers. I need to attack this issue differently though, because everyone else either comes from a piano background, or has fallen into the old habits as everyone else. I decided to try to analyze guitar playing to create my samples. I started with clean samples, as everyone else was dealing with distortion… I’ll figure effects out later.

The first thing I noticed, is that however subtle, because I'm human, every note I play is unique. If I only sample a single scale, or a single string, there's not going to be enough variety to my tones. Furthermore I see the subtlety between hitting an E at the 7th fret of an A string, and hitting an E the 2nd fret of the D String. Sampling each string becomes a must for me. Likewise notes, when first played, have a distinct plucking sound. It’s what makes guitar a percussive instrument. So when I make samples I need to leave the pluck in. If I want to get rid of it, a note offset in the tracker will let me do a hammer-on and pull-offs. Trim the sample to the very instant the pluck sound happens. It's vital that the pluck is at the beginning, because when finger picking, the plucks happen at the exact same instance.

The next realization was that Pianos are different than guitars. Pianos can't do hammer-ons and pull-offs. Pitch bends are arbitrary in their curve, not linear. In short, to make a realistic sounding guitar, you need to track like you'd play. I need to watch my hands instead of just punching in notes.

Because I was lazy in my transcribing days, I had already had my own way to sort this out. Instead of looking at my PC keyboard as a piano, I thought of my keyboard as a fret board. The C key became an open string, the V Key was fret 1, G was fret 2, and so on. Given the keyboard layout:

Code: Select all
  s   d       g   h   j
z   x   c   v   b   h   m

Instead of seeing:

Code: Select all
  C#  Eb      F#  Ab  Bb
C   D   E   F   G   A   B

I saw Frets, starting with the C key:
Code: Select all
  x   x       2   4   6
x   x   0   1   3   5   7

This actually let me track intuitively with the guitar. The choice of the C key for an open string was arbitrary, as I had tuned my initial sample using this technique to C (I recorded the 9th fret). However, the subsequent samples for other strings were all sampled at the 9th fret, to match. it was actually during this time that I tried to make 6 XI instruments of each string, using every 2nd fret per sample, for 12 frets. Because I was a teenager, and not a sound engineer nor a robot, I gave up when I found I couldn't play consistent enough to record and equalize 36 samples. 9th fret actually was a decent middle ground, and my open strings sounded close to an open sample. It worked well enough.

Next, I found that an up-stroke was different than a down-stroke. I had tried various methods of sampling this. My conclusion, was that it wasn’t how the pick hit the string, but the direction and speed which the pick hits multiple strings. This means one of two things: Either you record 2 samples of each chord you play, or you need to subtlety adjust the playback of each note, by delaying the sample. This proves to be VERY tricky, as it often requires smaller increments than a tick, thus you either need to increase the tracker tempo, and lines per beat, or you need to do some tricky offsets both delay triggering notes, and offsetting the notes in the pattern. Strumming with single notes to this day is one of the trickiest things I have done reliably, and I have only done it to prove it can be done.

After I had figured out the mechanics of getting stuff into the tracker, I decided to Add some effects. By this time I was working with a Pentium II 300 with Windows 98. Cool Edit had it’s own effects I could add to samples, and as I worked with them, I found that getting a good consistent sound out of them was incredibly difficult. Single notes could not play distorted chords well if the distortion was added to the sample. You needed to arpeggio more to give each note space to breathe. If you played more that 2 or 3 notes together, you would get a loud muddy distorted mess, instead of a cohesive chord.

It was at this point I began to play with recording chord sequences. By far, this was the most natural sounding guitar for old school trackers. It gives the most realism, but it always felt like cheating. After the novelty wore off, I started to record just individual chords, and add them into tracks. For the most part if I sampled in the same day, I could get consistent results with minimal sample hacking.

Step 3: Platform Upgrade

It was in this mixed state of recorded chords and individual strings to which my development stagnated. It wasn’t until the first beta of Psycle with VST support, that I got back into my quest for realistic tracked guitar. The ability to add my Effects to my samples in real time got me past my biggest stumbling block – the alteration of effects when the sample is sped up.

After finding some good free VST effects, I started writing some stuff using my original samples, which were about 7 or 8 years old by that time. I was surprised at the difference that adding the effects real time to a clean set of samples had increased the realism. The distortion had a uniform behavior, while the actual dynamics of the notes played off each other as they would from a guitar. Gone was the muddiness of the multiple-distorted notes of individual notes. Chords were now cohesive, with a good singular crunch to the tone.

Basically, I modeled my sound after an actual guitar rig. Sampler at one end to play my guitar, Distortion and other effects in between, then an amp modeler right at the end of the effects chain, to let me get a good realistic sound. Then any EQ/recording compression and volume adjusters came next as if it were a studio feed.

From there, it became all about technique again… No longer did I need to figure out the tricks to dealing with distortion, or worry about compromising a sample’s integrity for the effect. I could just play, and deal with my dials and slider in the VST interface. If the guitar was distorted, I could even get away with using a few less samples in certain cases. Guitar tracking had become much, MUCH easier.

But there were still problems. Arpeggios were still better than strummed chords. If you had a droning tone from a specific note, it still sounded unnaturally like the same note over and over again (Which it technically is). The choices fo fixing remain the same.... Unwieldy pattern length, or a host of offset tricks.

This is where I started running into Guitar VSTi and sound fonts. As I looked into these options, most VSTi have their own effects built into them. Sometimes the control is less than desirable. In other cases, the guitar’s base samples have used the SAME TECHNIQUES although to a lesser degree, as the metal MOD trackers of yester-year used to make the notes flow together better for Piano users. Likewise, because the VSTi is designed for Piano users, the subtlety of different strings on the guitar is often lost. In some extreme cases, I have found that some of these so-called Guitar simulators don’t sound like guitars at all… And one or two that I tried, seem to have issues with playing multiple notes at the same time. The realism issues are back with a vengeance.

So for now, my preference for tracking realistic guitar is by using a mix of clean single notes and chords, passed through several VST effects. I tend to favor individual notes as opposed to chords, because, often in guitar, you play with your chords, with a simple pull-off or hammer-on while strumming, and figuring out the offset on a single sample to deal with hammer-ons and pull-offs is not worth the effort. I live with percussive all-at-once strumming, or I try and hide it in the mix with other instruments such as drums or a second guitar with more movement, and usually slightly overpowering the first.
Posts: 15
Joined: Fri Jun 29, 2007 12:14 am

Postby tenfour » Wed Mar 17, 2010 5:11 am

very interesting to see such a detailed account of your technique - I think it's important to analyze these things and come up with a technique that means something - that has a purpose.

My approach is a bit different, although I think as technology advances in trackers, they will converge, as you can probably tell from my round 23 and round47 entries.

1) I start with almost any single sample as long as it has similar harmonic characteristics to some crap guitar.
2) I give it a suitable envelope in the instrument editor - and using this i can fake a guitar compressor before distortion.
3) I add FX until it a single note sounds like a convincing guitar
4) I track until my head explodes

I don't think so much about the audio effects though. I focus mainly (95%) on tracking. Using pitch bends, "accidents", delays, and other ways to simulate real guitar techniques, the sound comes alive and I don't think it's necessary to use sophisticated guitar samples. Of course that's only if there's sufficient distortion to hide the fact that the tone never changes. Thus my attempts at this pre-renoise era were a complete failure.

What makes it a guitar performance and not a piano performance is the technique & expression in the performance -- in the tracking. It is really the only thing that will make it sound realistic. The moment that a slide is too slow or something is too robotic, the ear discards it as being a realistic guitar performance. I try to think of the melody at a high level and make sure the message comes across through articulation in the tracking, not just the stream of notes. I close my eyes and if I picture a person playing it on guitar, then it's OK. If it's a stretch, then I figure out why, and fix it.

All this being said though... a real performance is still usually the best :) But I do like having the control over the performance with this kind of precision (ALL HAIL TRACKERS).

It was a pleasure to read your account.

Renoise's delay column really helps make delays easier to pull off. Check it out for doing chords. But I guess you're a psycle man; not sure about that.

The more experience we get in both guitar and tracking, the more we are able to adapt one to the other. Trackers will never be graceful at pulling off a beautiful classical guitar solo piece, but we adapt the music we compose with the knowledge that it will be put into a tracker, and then we can find the best of both worlds.

User avatar
Posts: 66
Joined: Tue Oct 02, 2007 7:33 am
Location: #musicdsp on EFNet

Postby organic io » Wed Mar 17, 2010 11:53 am

fingersoup, that was really interesting... Good lunch break reading :) I'm going to try out some of these techniques sometime when I get a chance, probably with some soundfonts.
User avatar
organic io
Compo Admin
Compo Admin
Posts: 1535
Joined: Thu Apr 06, 2006 11:55 am

Postby FingerSoup » Thu Mar 18, 2010 7:26 am

tenfour wrote:What makes it a guitar performance and not a piano performance is the technique & expression in the performance -- in the tracking. It is really the only thing that will make it sound realistic. The moment that a slide is too slow or something is too robotic, the ear discards it as being a realistic guitar performance. I try to think of the melody at a high level and make sure the message comes across through articulation in the tracking, not just the stream of notes. I close my eyes and if I picture a person playing it on guitar, then it's OK. If it's a stretch, then I figure out why, and fix it.

Very true... But it also involves the sampling technique as much as the tracker note techniques... Using note offsets for hammer-ons and pull-offs are one thing, but choosing realistic chords is another, and so is getting the sample right. There are so many good MODs that use guitar... And the MUSIC is convincing, despite the guitar sound not actually sounding like guitar... There's also lots of songs that I sat and visualized what it would be like if an actual guitar were used... This was the real passion for me to get guitar right... I felt trackers, as a tool, could do better. I was right, but it takes LOTS of time, patience, and work. Especially in the pre-VST days. Even I take shortcuts which don't sound realistic because of this.... I just take different shortcuts.

Likewise, I think there is a lot of value to the old school thinking. The fact that I deconstructed why everyone else was doing what they were doing shows that. There is a lot of logic to what they did... I just felt of making a clean break from the old school of thought and tried to focus efforts on finding shortcuts and tricks that I could employ for my ears. I'm sure there are people who would say my guitar doesn't sound right... And lets face it, even I see compromise in my work. But as a guitarist with limited piano knowledge, I see things in a way where I look for certain tonal qualities that a piano player may not... When I notice a guitar solo sounds like a string synth solo, I take particular notice, because it takes the percussiveness out of the instrument. Having the full sample, complete with string-pluck sound allows me to do this. I'm not trying to call anyone else wrong - I'm just trying to convey MY experience in an educational way...
Posts: 15
Joined: Fri Jun 29, 2007 12:14 am

Postby Airmann » Thu Mar 18, 2010 2:17 pm

wow, long article haven't completely read, yet, but maybe will

one question in advance: why do you focus so intensively on trackers ? I ask because a DAW like Cubase or Reaper may serve you much better for recording and editing natural instruments. I mean: you could use a spoon to dig the garden, but you also could use a spade. Isn't it a bit painful to produce guitar songs just using a tracker ?

Thanks to Rewire you also can use the DAW and Renoise together. I did so for my entry this round.

Of course Renoise's recording features will also be improved in the future. I'm really looking forward to WAV track support. Maybe by that time Renoise will be everything you need.
Posts: 159
Joined: Sun Aug 31, 2008 4:51 pm
Location: Germany

Postby FingerSoup » Sat Mar 20, 2010 7:48 am

Mostly because back in the day, DAW wasn't possible for me, and then I learned to appreciate aspects of tracking. It's out of pure stubbornness in some cases. Likewise, I am no drummer, and I think that Tracking offers an easy way to make drum tracks. It's a tool I'm comfortable with.

Mostly though, it's "Just because....", and it's fun.
Posts: 15
Joined: Fri Jun 29, 2007 12:14 am

Return to Tracking / Demoscene

Who is online

Users browsing this forum: No registered users and 1 guest