What makes a chord follow poorly or well from another?

I've been designing a computer program that learns what makes chordal motion sound good or bad, and I've had had a degree of success so far, but I would like to improve its performance as much as possible. To do this, I need to give it features to look for in progressions, features that help to determine how good or bad a progression will sound. Some of the features that I know affect the quality of a progression are the distance that the voices travel, what kind of motion they have relative to each other (e.g. contrary, parallel, similar, or oblique), whether dissonances are prepared, the absence or presence of parallel perfect consonances between pairs of voices, whether notes fall in each other's critical bands, and what notes follow the preceding notes. Beyond that, I don't have a whole lot of ideas. And so I pose a question that every composer should ask: what are the factors that make a two-chord progression sound good or bad?

Just that..... common chords tones, uncommon chord tones(look up god chords), no parallel 5ths/ octaves, no hidden 5ths /octaves, contrary motion... stuff like that

I gave some more thought to the question, and the broad answer, I think, is that almost anything you can say about a chord progression will play some role in determining how good it sounds. Virtually every characteristic you can think of will coincide more with either nice progressions or bad ones. So the question can be answered by answering the question: What are the properties that a two-chord progression can have? They can be very outlandish properties as long as they aren't 50/50 divided between producing a pleasant sound and a displeasing one.

I think two chords is very little for a chord progression. Only if you have V - I will determine a tonality.

I also belive that even in tonal music, every chord can follow another one with success. It depends on the effect you want.

On 8/16/2018 at 6:51 AM, Polaris said:

what are the factors that make a two-chord progression sound good or bad?

I think your thread title, and this question, are two different things.

Voice leading makes it sound "smooth", but smooth is not necessarily "good", which becomes increasingly subjective at a point.

The "good" aspect comes from the relationships between the chords themselves, and the between the chords and melody. The details of the former have been refined over centuries to the point that you can literally just use any progression that's been used before. The latter is as easy as looking to see what chord tones are present in the melody itself.

Every melody worth its salt implies a harmonic progression all by itself. 

I knew someone would say that it's subjective. I agree: it's subjective. That doesn't mean there aren't factors that help people decide whether they do or don't like a pair of chords together, though. Whether a shirt being lime green or not is a bad thing or a good thing is subjective. Its color nevertheless plays a role in helping people decide (provided they're not color blind).

When I say "chord" I mean all of the notes that are sounding. I'm not making a distinction between "the chord" and "the melody." Anything in the melody is a part of the sounding chord.

I disagree that it's a simple matter of using a progression that has been used before. Many progressions that have been used before sound bad to me. And music theory is very frequently helpless to explain why. Yes, it comes down to my subjective opinion. But what is influencing my opinion? And what things influence other people's opinions on a chord progression?

9 hours ago, Polaris said:

I knew someone would say that it's subjective. I agree: it's subjective. That doesn't mean there aren't factors that help people decide whether they do or don't like a pair of chords together, though.

I didn't say there wasn't, in fact: I explicitly said why some work and others have told you as well.

Taken from the same key/scale/mode, common tones, leading tones, stepwise motion, relationship to the melody, etc. That's why the progression works.

Voice leading is about creating independence for the different lines that make up the chord and making changes to nearest note because it's easiest to sing. That's why it sounds smooth.

Further, can I ask exactly what the point of the program is? This is a very easy thing for composers to do all on their own.

I have often written a melody to be played against another melody, using common tones, avoiding parallel perfect consonances, utilizing stepwise motion, etc. and ended up with a combination that sounds bad even though all of the standard rules have been followed and the melodies are strong individually. The purpose of this program is to figure out what kinds of features in a chord progression are correlated with bad effects of that kind so that I can avoid producing them in the future. A program that learns to produce consistently good progressions can tell me how to do it myself.

So far, in addition to what I listed in my original post, we just have sharing a scale and following the tendencies of leading tones. I believe there are more factors involved than that. In fact, I know there are, having investigated a few of them myself. It would be nice if people could try to think of some more things.

3 hours ago, Polaris said:

I have often written a melody to be played against another melody, using common tones, avoiding parallel perfect consonances, utilizing stepwise motion, etc. and ended up with a combination that sounds bad even though all of the standard rules have been followed and the melodies are strong individually. The purpose of this program is to figure out what kinds of features in a chord progression are correlated with bad effects of that kind so that I can avoid producing them in the future. A program that learns to produce consistently good progressions can tell me how to do it myself.

So far, in addition to what I listed in my original post, we just have sharing a scale and following the tendencies of leading tones. I believe there are more factors involved than that. In fact, I know there are, having investigated a few of them myself. It would be nice if people could try to think of some more things.

 

This provides a bit more insight, and I think I can see where your frustrations and confusion are arising.

You don't need a computer program to teach you this, you just need to know the theory better. Namely: Modes & Levels, as well as chord tones and non-chord tones.

The first thing I think that's getting you is the assumption that two harmonies in succession, formed by interlocking melodies = a progression, but it does not necessarily. In doing so, you're probably treating everything as if it's a chorale, which isn't going to work if it's not a chorale. 

A chord progression is a shift of level that happens when one modal frame is temporarily contrasted against another.  So for example, a way that you could melodically think of I - IV - V - I in C, is not as C - F - G - C, but rather Ionian - Lydian - Mixolydian - Ionian. By stacking thirds on those roots, you then get chords. However, that progression is still implied just by those root notes alone.  

Two or more melodies may vertically create triads themselves, but this does not mean the progression has changed, and I'm about to demonstrate why:

This is one of the most famous themes in recent times:

The Harry Potter theme. Except in the actual score, it's harmonized like this.

The top note is the melody, and the bottom two are harmony parts and it's all played over the root note in the bassline. You'll notice they are nothing but parallel movement. In fact, when the triads are kept in the same position like this and moved chromatically, it's called "planing" and John Williams uses it extensively. Let's take a closer look at the first figure, which is all played over a single A note in the bass.

I've highlighted the non-chord tone here in the first bar. Specifically, this kind of non-chord tone is called a "neighbor tone" because it neighbors (chromatically in this case) the chord tone.

Now watch what happens when I bring back the harmony parts to the melody:

Three neighbor tones at once instead of just one. You could play this over the full A Minor chord and it would still work just as well. You could keep harmonizing the melody like this (and Williams does) for the entire progression and it would still work. It's just harmonizing the melody in thirds downward, and emphasizing chord tones of the current underlying chord in the progression. 

This is not like a chorale, where how many tones the human voice can leap, and how quickly, are limited. Thus, in such a case, each new note is often the next chord in the progression or at least a chord tone, and the voice leading is there to make the smoothest transition and ensure that it's easy to sing; the top voice is the melody, like so:

I hope this helps!

Thank you for your response. My problem, though, isn't that I regard everything as a chorale. I'm looking at what makes two harmonies ("harmony" is probably a better word than "chord," simply because the word "chord" comes with so much baggage, like people thinking of there being a distinction between "the chord and the melody" or classifying certain tones in the chord as "non-chordal," neither of which affect my considerations one way or the other) in succession sound good or bad in any context, including in the type of situation that occurs in the Harry Potter theme. Yes, I know that some notes (and sometimes even whole chords if it suits a theorist) are typically classified as non-harmonic, and I'm familiar with the usual figures like suspensions, neighbor tones, and so forth. Such devices are all changes of harmony. That's what I'm looking at--changes in the overall sound.

On a side note, I have to disagree with the idea that only the top part has melodic implications. All of the intervals that occur in the progression, including those created by the difference tones, have melodic significance. The upper part may be more prominent, as is often the case, but the other horizontal (and diagonal) connections between the notes are heard to some extent as well.

Then I am afraid there's nothing anyone can tell you that is to likely to help that they haven't already.

It's all about voice leading and the voicing of the chord.  

Literally and chord can be followed by any other chord and it can sound good. ... it can also sound terrible. With poor voicings, even a ii - V - I can sound gross.

4 hours ago, robinjessome said:

It's all about voice leading and the voicing of the chord.  

Literally and chord can be followed by any other chord and it can sound good. ... it can also sound terrible. With poor voicings, even a ii - V - I can sound gross.

If it were "all" about voice leading, 99% of rock music, a significant amount of guitar music in general, or basslines consisting solely of root notes would sound terrible — but they don't. I think a lot of people here are thinking smooth motion is synonymous to "good", which is a bit of a mistake. 

Honestly, this just isn't rocket science. Examine your melody and pick out the chord tones, take the scale and make an 8 bar bassline consisting of root notes and go from there, examine existing scores and find out what progressions they used that you like; how many film scores don't use the same chromatic-mediant changes? 

Revisiting this thread years later, now that I've learned more about what makes music tick.

One of the main "secrets" (I put the word in quotation marks because it isn't particularly obscure knowledge) I've found--and I don't recall anyone mentioning this here--is the fact that chord progressions sound best when the chord roots progress rather than regress. Progress means: move up a second or down a third or up a perfect fourth or any inversion of the aforementioned motions. Doing this creates an impression that the music is moving forward rather than rowing against the current. It's surprising to me no one mentioned this, because it's fairly common knowledge among music theorists and, even when not spelled out by them, can be inferred by looking at a typical map of "allowed" chord progressions.

Another piece of advice I've discovered for myself is to be very careful with what chord inversions you use in succession. The ear keeps track of where the root of each chord is positioned, and changing inversion can therefore create an impression of an awkward leap even when the voices appear to move smoothly. As such, it isn't a bad idea to ensure that the chord roots proceed in a melodious fashion.

One idea I reject is that minimizing the distance the voices move creates a more pleasant effect. By that logic, you may as well not move the voices at all for the entirety of a composition. Another piece of advice I reject is that keeping a common tone in one voice leads to a better effect than doing the opposite. The musical literature is rife with examples where the common tone is taken up by a different voice while the one that carried the tone moves up or down. Generally, it sounds fine.

One thing that sounds definitely bad is, of course, placing tones within a critical band of each other. This usually happens when composers put major or minor thirds down in the bass range. The effect is commonly referred to as muddy, and for good reason.

Other than that, I can't think of any particularly great advice for writing good chord progressions that isn't common knowledge to anyone who has studied counterpoint and harmony very extensively. If anyone has some further thoughts on the subject, though, I would love to hear them.

2 hours ago, Polaris said:

One of the main "secrets" (I put the word in quotation marks because it isn't particularly obscure knowledge) I've found--and I don't recall anyone mentioning this here--is the fact that chord progressions sound best when the chord roots progress rather than regress. Progress means: move up a second or down a third or up a perfect fourth or any inversion of the aforementioned motions. Doing this creates an impression that the music is moving forward rather than rowing against the current. It's surprising to me no one mentioned this, because it's fairly common knowledge among music theorists and, even when not spelled out by them, can be inferred by looking at a typical map of "allowed" chord progressions.

I have to disagree with this.  Harmonic regressions which move in the opposite direction as the progressive movement can sound very good and be very useful in a chord progression.  The most common example of this is just movement from the tonic to the dominant (I - V).  The whole concept of negative harmony is based on this idea and it can often sound very good and interesting.  Progressive movement can be considered "stronger" but "stronger" is not always better.

I have a rule to propose for what can make sonorities sound good when following one another.  If the outer voices (or more precisely, the melody and the bass) are chosen logically it helps create a good skeleton for the resulting sonority progression to sound good.  (I also call them sonorities because if they're pan-diatonic you're probably going to think of them the whole scale/mode at a time like @AngelCityOutlaw mentioned).  Great topic!

One thing I forgot to mention is cross relations. There are two forms of them. One is the juxtaposition of a note and its "altered" form between two different voices (e.g. using the raised seventh degree in a minor key right after using the same key's flattened seventh degree in another voice). The other is the outlining of a tritone between a pair of voices, particularly when they both move in stepwise fashion. Both cross relations, especially the latter, tend to sound harsh and unmusical.

2 hours ago, Polaris said:

One thing I forgot to mention is cross relations. There are two forms of them. One is the juxtaposition of a note and its "altered" form between two different voices (e.g. using the raised seventh degree in a minor key right after using the same key's flattened seventh degree in another voice). The other is the outlining of a tritone between a pair of voices, particularly when they both move in stepwise fashion. Both cross relations, especially the latter, tend to sound harsh and unmusical.

No I have to disagree with this! They can be harsh sounding but beautiful if used with purpose. English Renaissance composers like Willams Byrd used them beautifully. For me, I use tons of those minor seconds which includes false relation in my 6 voice fugue:

Also I haven't heard the definition of the latter as cross relation!

Great topic!

Henry

7 hours ago, Henry Ng Tsz Kiu said:

No I have to disagree with this! They can be harsh sounding but beautiful if used with purpose. English Renaissance composers like Willams Byrd used them beautifully. For me, I use tons of those minor seconds which includes false relation in my 6 voice fugue:

Also I haven't heard the definition of the latter as cross relation!

Great topic!

Henry

 

That's a really beautiful fugue. Kudos to you for composing it.

Anyway, my point isn't really that cross relations, chord regressions, etc. shouldn't ever be used so much as it is that such devices undermine the smoothness of the musical texture. A similar statement could be made of introducing dissonance into a piece, but we all know dissonance has its place in music. It just has to be used in a carefully controlled fashion. The same can be said for cross relations, chord regressions, and some of the other things mentioned in this thread.

21 hours ago, PeterthePapercomPoser said:

 

I have a rule to propose for what can make sonorities sound good when following one another.  If the outer voices (or more precisely, the melody and the bass) are chosen logically it helps create a good skeleton for the resulting sonority progression to sound good.  

 

I totally agree, and I think this applies to any kind of musical system based on tonal harmony (by thirds, fourths or whatever). In solo piano compositions it is very well observed, but in orchestra it is the same taking into account doublings and layers.

Especially taking care when writing the outer voices is sound advice, I'd say (and something I've seen a great many music theorists recommend). The outer voices are normally more audible than the inner voices, so it's particularly important to compose them gracefully, whereas the inner voices can get away with being relatively bland. There's good precedent for this approach, as well, given that Mozart, one of the most brilliant composers, is said to have started by writing the outer voices and only later filling in the middle ones. 

On 10/14/2024 at 12:17 AM, Polaris said:

One thing I forgot to mention is cross relations. There are two forms of them. One is the juxtaposition of a note and its "altered" form between two different voices (e.g. using the raised seventh degree in a minor key right after using the same key's flattened seventh degree in another voice). The other is the outlining of a tritone between a pair of voices, particularly when they both move in stepwise fashion. Both cross relations, especially the latter, tend to sound harsh and unmusical.

On 10/14/2024 at 10:32 AM, Polaris said:

Anyway, my point isn't really that cross relations, chord regressions, etc. shouldn't ever be used so much as it is that such devices undermine the smoothness of the musical texture. A similar statement could be made of introducing dissonance into a piece, but we all know dissonance has its place in music. It just has to be used in a carefully controlled fashion. The same can be said for cross relations, chord regressions, and some of the other things mentioned in this thread.

I have an example for you of a piece that includes cross relations between natural and flattened 7th degree which doesn't (imo) at all "undermine the smoothness of the musical texture".  I'll copy what I said about it in the beginning of my Favorite Video Game Music Tracks? thread:

This is a track from the original "Star Fox" for the Super Nintendo Entertainment System.  "Titania" is an ice planet in the game that you have to traverse in the novice course to the planet "Venom" the ultimate seat of the antagonist "Andross".  I like this track because of it's cool house beats and use of both the natural and flat 7th degree of the scale at the same time.  If you listen carefully, the bass has a kind of tonic pedal-like riff that includes a flat 7th while the melody is playing a natural 7th.

Edit:  I think you have to include the factor of musical memory and how the ear, over time, will get used to a certain sound if it is repeated enough.  In this case the tonic/b7th pedal riff is repeated throughout the track causing the ear to accept it without objection.  Then the natural 7th comes in in the melody after a certain amount of time with all it's own melodic logic for why that natural 7th has to be there and it all just makes sense.

15 hours ago, PeterthePapercomPoser said:

I have an example for you of a piece that includes cross relations between natural and flattened 7th degree which doesn't (imo) at all "undermine the smoothness of the musical texture".  I'll copy what I said about it in the beginning of my Favorite Video Game Music Tracks? thread:

This is a track from the original "Star Fox" for the Super Nintendo Entertainment System.  "Titania" is an ice planet in the game that you have to traverse in the novice course to the planet "Venom" the ultimate seat of the antagonist "Andross".  I like this track because of it's cool house beats and use of both the natural and flat 7th degree of the scale at the same time.  If you listen carefully, the bass has a kind of tonic pedal-like riff that includes a flat 7th while the melody is playing a natural 7th.

[Youtube Video]

Edit:  I think you have to include the factor of musical memory and how the ear, over time, will get used to a certain sound if it is repeated enough.  In this case the tonic/b7th pedal riff is repeated throughout the track causing the ear to accept it without objection.  Then the natural 7th comes in in the melody after a certain amount of time with all it's own melodic logic for why that natural 7th has to be there and it all just makes sense.

 

Nice music. I didn't hear anything that seemed out of place when I gave it a listen.

True, musical memory is definitely a factor involved in determining how well-received a musical gesture will be. That's why, for example, a modern audience will often accept things like unprepared dissonances without batting an eyelash. Most people today have been exposed to such things all their lives and therefore hear them without being in the least shocked or surprised.

This seems like the perfect forum to ask this question...what chord fits best in mm.55? There's a great opportunity for an emerging, bright sound, but idk what chord works the best.

On 8/25/2018 at 6:24 PM, AngelCityOutlaw said:

I think a lot of people here are thinking smooth motion is synonymous to "good", which is a bit of a mistake. 

Agree. What's good and bad is simply judgement. It's down to composers how they value chord progressions in context of melody, sequence, effect and so on.   Personally, most chords happen through of the movement of parts. Sometimes the result is harsh, sometimes concordant.   

On 10/19/2024 at 3:53 PM, Quinn said:

Personally, most chords happen through of the movement of parts. Sometimes the result is harsh, sometimes concordant.   

Exactly.

In my own writing I honestly don't even think about "chord progressions" at all anymore. It is ultimately a very restrictive view on harmony. A more horizontal, contrapuntal way of thinking is almost always better.

I just write a line and then thicken it in any number of ways. Sometimes it will be as simple as thirds and octaves, other times you could examine it as full triads or extended chords, sometimes it's contrary motion, sometimes just a weird cluster that worked at that moment.

Then I often do the same to different melodies that may be occurring at the same time.

I find the results much more musically, aesthetically and intellectually stimulating than just "chords + melody"