ScalerAudio2 plugin: how accurate is key detection?

Scaler 2 General Discussion
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A general question about the audio detection in the ScalerAudio2 plugin…

I’ve decided to follow an often made suggestion to improve my general skills by trying to recreate a recorded track that I like inside my DAW. It’s not a complex piece (it’s house music, after all!) but I am getting conflicting results as regards the key that the track is in.

I have HornetSongKey, which I’ve had rather mixed results with, and which gave me the key of Gb Major with a (variable) 60% - 70% probability. Some internet searches threw up a few commercial plugins that are specifically for key detection, but rather than splash out now, I then dropped the track onto the site at GetSongKey<dot.com>. This site told me that the track is in F Minor… A point to note: I dropped the entire track onto the above website, which obviously includes all the vocal sections. For purposes of key detection in my DAW I chose one six bar section late in the song in which only the drums, bass, and keyboards feature (not even lead lines on keys).

ScalerAudio2 doesn’t so much state an exact key, rather it lists some keys and the number of notes within that key that have been detected, as well as the number of chords within that key that are (presumably) within the sampled audio. So, top of this list is Eb Minor, with 7/8 notes, and 7/9 chords. The thing is, directly below are SEVENTEEN other scales all with 7/8 notes, and 7/9 chords. The third option in said list is Gb Major, which backs up what the Hornet plugin detected, but at odds with the website (which is understood to be reliable) which stated F Minor, and which is not in any of the alternative scale options given by ScalerAudio2.

Now, for the purposes of recreating the simple bass line and chord stabs of this song project, it’s not actually going to matter too much, as I have a reasonably accurate ear pitch. But, it would be nice to understand a little more about what/how Scaler detects keys. Or is this plugin still primarily a midi tool - meaning that I could benefit from purchasing a dedicated “song key detector” plugin for audio?

later edit: well! I did two things. I purchased the Antares Auto-Key 2 because it was half price on a holiday promotion. I then restarted my DAW once this new plugin was activated. This time I reran the ScalerAudio detection, and it picked Gb Major as it’s first choice! Good right? Well, the Antares plugin (I believed this to be quite a widely regarded plugin) chose C# Minor as the key!

So it’s all still a bit confusing to be honest :slight_smile:

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Yes it is confusing. To make matters worse Scaler EQ and Scaler 2 audio detections are tuned differently.
If I want to know the key of a tune I use Scaler EQ as I find it very accurate, Scaler 2 however is tuned to find the harmonic content (chord etc) so at times it is not so descriptive at telling you the actual key and scale of the tune as it is designed for chords!

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so, if I have understood you correctly, the “key detection” inside Scaler 2 isn’t designed to detect a “key signature” but is more focused on simply detecting which chord is being played, to suggest scales and keys which that chord fits? A sequence of keys (despite they may be “in key” as played) will be treated more as a sequence of chords, not necessarily an “in key” arrangement?

Interesting. Never thought I’d need to understand such a difference :slight_smile:

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Could be that its in more than one key. Out of interest what is the track?

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A good point indeed, and I’ll tell you the track, but just to reiterate that I had isolated a short-ish pattern of repeat bars that contain only the drums, bass, and keys riff. No key change happened within that section.

The track is (specifically) Days Like This, by Shaun Escoffery, as remixed by Booker T on his “Quintessential Sessions” album.

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A classic although not familiar with that mix.
I stuck it through Melodyne & it showed a C# minor modulating to A minor
It’s possible that the mix could be pitched up if its part of a mix.
It definitely changes key
One thing i really hope scaler 3 can do is have better analysis of both midi & audio of the key changes it hears. I think that would be super handy to understand whats going on.

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Thank you for doing that, and for helping.

Like many such tracks, the whole album contains the “DJ mix” in which the song is blended into a wider mix (usually in one very long track), while the rest of the album then also contains each individual track. On this basis I felt that the insular track was a reasonable basis to try to extract a key.

I think that the very least Scaler should offer is the choice - i.e. would I like the “key” as the key centre of an audio/midi clip; or would I like the “key” as the actual key that the music is in? To discover later that "yes well, it’s actually tuned differently so this isn’t in fact ‘the key’ feels a bit… deceptive? Why it would require two separate plugins, one of which I will never have a need for, rather baffles me if I’m honest.

WHY does a piece of software marketed as helping with music theory and composition NOT actually give me a “key signature”? How very odd. You have used Melodyne (a bit beyond my budget at the moment), I bought the Antares Auto-Key and Scaler, and nothing agrees, it’s still up for debate!