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The passing of FiftyOneFifty

It is with deep sadness we announce that another of our hosts and friends Donald Grier, known to us as FiftyOneFifty, has passed away.

FiftyOneFifty's frat brother Randy Hall has written an lovely piece. The team at Linuxlugcast are preparing our own tribute if you want to contribute an audio file you can email Honkeymagoo or join the show.

Our thoughts go out to his friends and family at this difficult time.

hpr1754 :: D7? Why Seven?

I explain what 7th chords are and when to use them.

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Hosted by Jon Kulp on 2015-04-23 is flagged as Clean and is released under a CC-BY-SA license.
Tags: chords, music theory, music, harmony.
Listen in ogg, spx, or mp3 format. | Comments (5)

In this episode I respond to one of the community-requested topics ("Music Theory") and try to explain what seventh chords are and why they are used. Below are some of the terms that I use in the course of the discussion.

  • Interval: The distance between two pitches (sounded either consecutively or simultaneously)
  • Consonance: Relatively stable sound between two or more pitches
  • Dissonance: Relatively unstable sound between two or more pitches. Dissonance often needs a "resolution" to consonance
  • Chord: three or more notes sounded together
  • Chord progression: a succession of chords
  • Triad: a chord with 3 pitches, the adjacent pitches separated by the interval of the 3rd.
  • Seventh chord: a chord with 4 pitches, the adjacent pitches separated by the interval of the 3rd.
  • Tonality: harmonic system that governs the use of major and minor keys
  • Tonic: the central tone of a piece of music
  • Mode: major or minor [e.g. Symphony no. 5 in C minor]
  • Modulation: the process of changing keys within a piece of music
  • Scale: Ascending or descending series of notes that define a key or tonality, with a specific arrangements of half-steps and whole-steps. Major and Minor scales are most common in Western music

Free public-domain music reference book: Music Notation and Terminology by Karl Wilson Gehrkens: (see ch. 18)

Free Online Music Dictionary:


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Comment #1 posted on 2015-04-10T19:56:42Z by FiftyOneFifty


I thought this was going to be a podcast on Klingon battle cruisers.

Comment #2 posted on 2015-04-23T02:27:06Z by Jon Kulp


Sorry Fifty, I don't even know what those are! Maybe you can record a follow-up. I actually thought the title might be confused with Star Wars droids, the Klingons never occurred to me.

Comment #3 posted on 2015-04-29T05:26:51Z by thelovebug


I found this incredibly interesting as a musician with virtually no formal training... I look forward to hearing more on the theory of chord progressions!

Thanks Jon!

Next: Major 7ths? Probably my favourite chord to (over)use.

Comment #4 posted on 2015-05-10T00:13:00Z by FiftyOneFifty

Explaining myself

The Klingon ship from the original Star Trek series was a class D7 battle cruiser and you can still see the model still in use in the later series (Next Gen, DS9, Voyager).

Comment #5 posted on 2015-05-10T10:47:49Z by Jon Kulp

I kinda see the resemblance...

That ship actually looks like it has some dissonance in it, such as the tritone between the C and the F♯ that I mentioned in the d7 chord the

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