page 25, diminished chords

[PsychicSidekick]

I've noticed that in the extended Chord Theory section there is a formula for:
C diminished = 1, b3, b5
And then, below that, there are 7th chords
C maj 7, C min 7, C7, C min 7(b5) and... another C diminished. With a formula of
C diminished = 1, b3, b5, bb7

Do they have a same name? It would be odd because they have different formulas. Maybe the second diminished chord should be C diminished 7 or something, if something like that even exists...

Also, in Master the major scale, Justin writes out the chords in the key of G and the 7th chord is F#min7b5 and according to practical music theory it should be a diminished chord. So is it diminished or min7b5?

[Bootstrap]

This article will most likely clarify the nomenclature for you.

http://www.theguitarsuite.com/Theory/Dim-Chords.php

To answer your last question, a half diminished seventh chord is often referred to as a minor seven flat five.

Happy reading - if it doesn't fully explain things for you, ask some more questions.

[PsychicSidekick]

Thanks for the reply and the link. It explains my first question very well.

As for my second question, does it mean that every 7th diatonic chord in any given key would be half diminished or is it just the case when it comes to a key of G?

[Bootstrap]

Diatonically

Every vii chord played as a triad in every key will be a diminished chord.

Every vii chord played as a quadad in every key will be a min7 b5 (half diminished)

[PsychicSidekick]

I get it now. Thanks a lot.

[fint72]

The diminished triad chords are confusing me. Are they used much? If Justin does a lesson on them I can't find it.

[TB-AV]

The diminished triad chords are confusing me. Are they used much? If Justin does a lesson on them I can't find it.

The Blues is built around the concept of the b3 and b5. ... and b7 for that matter.

[fint72]

So how does one go about playing these diminished triad chords? They're just made up of root, flattened third and flattened fifth, right?

[steveo2]

The diminished triad chords are confusing me. Are they used much? If Justin does a lesson on them I can't find it.

I am sure there is a lessons here on them maybe in the Jazz section.
the diminished chord is not part of the major scale, the Minor 7 b5 i it is also know as the half diminished chord.
the bb7 of the diminished chord is very dissonant and is not common in pop music 

[shadowscott007]

Diminished chords I consider sort of advanced.  Depends on where you are on the journey, how much you need to know.  If you try to go farther than you need to, you can just confuse yourself.

Beginners - Level need to understand that they exist.  How the diminished chord (1 b3 b5) comes from the major scale.  Not too many beginner songs are gonna toss in the diminished chords.

Beginner/Intermediate - The diminished triad doesn't get played to much as a triad.  Usually it is buried inside the m7b5 (minor 7 flat 5, 1 b3 b5 b7) chord grips.  Justin has the common 6th string root and 5th string root grips.  Learn those.  You should be able to know a couple grips to play these if they show up in a tune you want to play.  But really doesn't happen a lot.  In fact if you want to get good at the grips go find a tune, or a groove that uses them.

Intermediate - there  is another common diminished chord type.  It has notes "outside" the major scale.  it is a Diminished7 chord, Dim7 (1 b3 b5 bb7 or 1 b3 b5 6).  Need to know the couple grips so you can use them when you see them...

Intermediate Plus - Dim7, m7b5 chords are a lot more common in the jazz, jazzier progressive, and the Malmsteen style metal.  They show up when you start using the harmonic minor scales, and can be used for all sorts of cool chord substitutions.  Go figure out how to use them in your own arrangements, compositions, solos, sky's the limit.  Master's level to PhD....

Shadow

[fint72]

I've been making my way through the Practical Music Theory PDF and am trying to memorise the (triad) chords in various keys of the major scale. The VII degree of each major key is a diminshed chord - but these are chords I do not know. I don't think I'm going to make the effort to learn them either - not at this point anyway. From what some of you have said above this seems sensible.

I know my Dominant Sevenths cos Justin taught me them - and I've learned to play some blues. I realise these chords are quadads rather than triads (thanks again J). Now I know there are also Minor Sevenths 1, 3b, 5, 7b), Major Sevenths (1, 3, 5, 7), Diminished Sevenths (1, 3b, 5b, 7bb) and Half-dimished Sevenths (1, 3b, 5b, 7b)!

[justinguitar]

Perfectly put Shadow!!