I've gone through a bunch of ♭VII-I and ♭III-I cadences in rock music. In C major, they are B♭-C and E♭-C.

Is there a specific name for the two cadences? So far, I've been calling them authentic cadence variants, since both ♭VII and ♭III are substituting for V. Others had been saying so, as well.

• On the right hand side of the pond, authentic = perfect. But I don't think they are. There's also #V-I.
– Tim
Commented Jul 11, 2019 at 9:23
• en.m.wikipedia.org/wiki/Backdoor_progression
– b3ko
Commented Jul 11, 2019 at 17:54
• @b3ko - That article is about bVII7-I, and my question is about bVII-I and bIII-I.
– user53472
Commented Jul 12, 2019 at 3:19
• Are you using the word "cadence" to mean "progression?" There are standard cadences, but the concept is different than simple chord progression. Commented Mar 8, 2022 at 14:01

No. A widely cited scholarly paper calls them just what you do, ♭VII-I and ♭III-I. It offers a plethora of adjectives to distinguish different kinds of cadences, but none have the centuries of weight of the terms for the cadences that Mozart used.

Edit: One might call them variants of the authentic cadence, but that's an awfully broad name, not the specific name that you ask for.

• @MaikaSakuranomiya I'm not sure where you got that information from. No theory books I'v ever seen mention any kind of III as a substitute for V and bVII will never be viewed in classical as authentic and from classical perspective will pull to bIII (the relative major).
– Dom
Commented Jul 13, 2019 at 21:10
• It isn't clear to me in what sense you could call either bIII-I or bVII-I even variants of an authentic cadence. Maybe you could expand on this idea....
– user39614
Commented Jul 14, 2019 at 4:09
• OP said that they were variants was the idea of OP's teacher (answer and its disbelieving comments were deleted.) Commented Jul 14, 2019 at 4:12
• I've totally seen papers that call cadences of III-I and VII-I type authentic variants, and VI-I and II-I plagal variants, e.g. in analyzing Rachmaninoff and other late Romantic music. Commented Jul 14, 2019 at 21:20
• @Mirlan that's still broader than what the OP hopes for. If those are called variants of authentic and plagal, then they exhaust all possible cadences ending on I, and one might as well replace the archaic word "plagal" with a postmodern "non-authentic." Commented Jul 14, 2019 at 22:48

I think you should distinguish between cadences and simple chord progression.

Cadences demark phrase or section endings.

A chord change that does not end a phrase or section is a simple progression.

In tonal harmony there are standard cadences: authentic, half, deceptive, and plagal. Some of the terminology gets applied to chord progressions in a more generic sense with no connection to phrase/section structure. Usage like cadential harmony or deceptive progression are examples.

In modal harmony, both folk music and Medieval/Renaissance music there are cadences other than those in tonal style. Now and then I've seen some names applied to modal cadences, but nothing like the standard naming in tonal style.

You could call `♭VII-I` a modal progression or cadence. I have seen that used as an actual structural ending in folk songs and it such as case cadence would be a appropriate description.

I've not seen `♭III-I` used as a true cadence, at least not commonly, but that kind of thing is a fairly common progression. You can describe the change as a chromatic mediant. It has a very distinctive sound.

Of course you can end a phrase with any kind of chord change. The question only becomes whether or not it's common enough to have a name. If it doesn't have a common name, it doesn't mean you can't use it as an ending.

The textbook Kostka, Harmony contains a classification chart for cadences...

```
Cadence type    First chord                     Second chord

Plagal          Does not contain leading tone   Tonic

Deceptive       Contains leading tone           Not tonic
Half            Does not contain leading tone   Not tonic
```

...it doesn't seem to be widely used, but it's logical. Also, it's followed by this statment...

A still more general but useful method of classifying cadences puts them into two groups: conclusive (authentic and plagal) and progressive (deceptive and half).

By that classification:

• `♭VII-I` is conclusive, plagal
• `♭III-I` is conclusive, plagal

...the critical point being there isn't a proper leading tone in those progressions.

• I feel like the "modal" bit is the closest this question has gotten to an answer that meets the intent, though. Just making something up, what if we encountered "I - IV - bVII (as V of...) - bIII - I." What would we call it? I feel like all Kostka's options would be misleading; when I hear "Half cadence" I expect it to end on V; if I hear plagal I expect IV - I... Commented Mar 8, 2022 at 19:33
• Yeah, I agree, anyone calling something a "half cadence", will make me think and end on `V`. Like I said, the Kostka chart isn't widely used. However, if the music actually had a structural break after `I IV bVII bIII`, and it was called a "progressive cadence" I would understand the meaning, other wording like "continuation cadence", etc. would make sense. Commented Mar 9, 2022 at 21:36
• In `I - IV - bVII (as V of...) - bIII - I` what is the cadence, `bVII (as V of...) - bIII` or `bIII - I`? Kostka's chart would call the latter progressive/half and the latter conclusive/plagal. Of course this assumes that `bVII bIII` isn't regarded as a key change. Commented Mar 9, 2022 at 21:40