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Has anybody modified a 12 bass?

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Ben-jammin

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I am kind of musing here. I did a search and didn't see a similar thread but if I missed it I apologize.

I never saw much of the benefit on a 12 bass of just having 6 major chords available. I understand that it's a limited instrument but it would make much more sense to me if it's crippled I would rather be limited to one key with majors and minors rather than have only majors for a few different keys. To that ends I think the key of F would make the most sense, it would require modifying the A, D, G chords to be minor. I am not sure how much work it would be to modify the mechanics of the bass system but a second option would be to just replace or retune the C#, F# and B reeds used in the chords. I could see the utility of a 12 bass then, as a kind of compact little knockabout. The more I think about it the more I'm kind of inclined to keep my eyes open for an old 12 bass to try it out.

Has anybody done this? I would be interested to hear if the mechanical method is viable and were the results ever really utilized.
 
You could also consider disabling the thirds on the chords, if it is easy to do this. This would give you open chords (root and fifth only) which could substitute for major, minor, or 7th chords. The sound of open chords works well for a lot of folk music and is even preferred by many folk accordionists.

FYI: There is a 24-bass system (sometimes called the "Darwin" system) that is offered on button boxes by a few accordion makers. It provides 12 bass notes and 12 open chords in a compact 6x4 arrangement that is fully chromatic. You can play any chord progression in any key (using open chords) and any bass run. I have never seen this on a small piano accordion, but it would be more versatile than a 12 bass Stradella with only major chords. I have a small CBA with this system.

I have attached a diagram of the standard arrangement. Other arrangements are possible.

Standard 24-Bass System.jpg
 
I may be misunderstanding you here, but surely you need at least 3 base notes available together with the relevant major, minors etc.
I can't think of any tunes which would use only one chord.
 
I may be misunderstanding you here, but surely you need at least 3 base notes available together with the relevant major, minors etc.
I can't think of any tunes which would use only one chord.
By a traditional definition chords are at least 3 parts. One could argue that open chords aren’t truly chords, but to me that’s just a question of terminology.

Open chords work by having the third (even as it’s not sounded) being implied by the rest of the musical context. So if you play an A open chord (A and E) when the melody is in the key of C the open A chord will be interpreted by the listener as being an A minor.

I don’t understand what your reply on one chord was referencing. In my proposed update to a 12 bass would have 9 of the bass buttons remain as original so the 6 in the bass row would remain as they are and the Bb, F, and C major would stay as major. Just modify the G,D and A major buttons to be minor. So you could play a wider array of songs with left hand accompanyment (after transcribing them to the key of F major or it’s relative D minor.)
 
Regarding your original post, Ben, I was talking to that old guy about his accordion restoration and he likes to work on 12 bass because they are basic and cheap to find on eBay. He said he likes to change the basses one down to Eb, or 2 to Ab because he likes to play in "horn" keys of Eb and Ab. And/or he likes to add another row of treble reeds to get some musette. It was an interesting concept, since I never played anything in Eb. I tried it and it was very interesting, a different sound, more nuanced, maybe because I play so much on G, C, or F.
 
FYI: There is a 24-bass system (sometimes called the "Darwin" system) that is offered on button boxes by a few accordion makers. It provides 12 bass notes and 12 open chords in a compact 6x4 arrangement that is fully chromatic. You can play any chord progression in any key (using open chords) and any bass run. I have never seen this on a small piano accordion, but it would be more versatile than a 12 bass Stradella with only major chords. I have a small CBA with this system.

Steve, What is the brand and model of your instrument or is it custom made?
 
In my proposed update to a 12 bass would have 9 of the bass buttons remain as original so the 6 in the bass row would remain as they are and the Bb, F, and C major would stay as major. Just modify the G,D and A major buttons to be minor. So you could play a wider array of songs with left hand accompanyment (after transcribing them to the key of F major or it’s relative D minor.)

That's a cool idea!

Although if you're playing in D minor, you'll probably want that A chord to remain major since the V chords of minor keys typically derive from the harmonic minor scale. You'd lose the ability to play the Am chord in F major, but that's rarely-used enough to not be much of a loss. And then you'd only have two buttons you'd need to alter. And since you're only changing the 3rd, that's only two bass machine connections you'll have to redo.

(Unless you decide to get really fancy and mod the A major to be an A7 by changing the 5th to a b7. That would sound great in Dm.)

I'm now imagining a bandolier-style holder, like harmonica players wear, but for multiple 12-bass accordions in different keys. :)
 
That's a cool idea!

Although if you're playing in D minor, you'll probably want that A chord to remain major since the V chords of minor keys typically derive from the harmonic minor scale. You'd lose the ability to play the Am chord in F major, but that's rarely-used enough to not be much of a loss. And then you'd only have two buttons you'd need to alter. And since you're only changing the 3rd, that's only two bass machine connections you'll have to redo.

(Unless you decide to get really fancy and mod the A major to be an A7 by changing the 5th to a b7. That would sound great in Dm.)

I'm now imagining a bandolier-style holder, like harmonica players wear, but for multiple 12-bass accordions in different keys. :)
I was actually having a similar thought about the A after thinking about it for a while. Would be interesting to try the A chord as an Open like Steve commented. Just put masking tape on the C# reed inlet and let it be implied minor or dim 7th.
 
I was actually having a similar thought about the A after thinking about it for a while. Would be interesting to try the A chord as an Open like Steve commented. Just put masking tape on the C# reed inlet and let it be implied minor or dim 7th.

True. But man, I'd hate to lose the third on a V chord. It's such an important contributor to the sound of that V-i cadence.

If you kept it as A major, and one day stumbled across a song that called for an Am in the key of F, you could always just play A bass with your C major chord. That would add up to an Am7, which might sound pretty good there.

(And by the way, the one chord moving to a three minor is one of my all-time favorite chord changes: Where is Your Heart, Torn, Super Trouper, It's a Heartache, Against the Wind, Cruel to be Kind, nearly every Alan Parsons Project song... the list goes on!)
 
True. But man, I'd hate to lose the third on a V chord. It's such an important contributor to the sound of that V-i cadence.

If you kept it as A major, and one day stumbled across a song that called for an Am in the key of F, you could always just play A bass with your C major chord. That would add up to an Am7, which might sound pretty good there.

(And by the way, the one chord moving to a three minor is one of my all-time favorite chord changes: Where is Your Heart, Torn, Super Trouper, It's a Heartache, Against the Wind, Cruel to be Kind, nearly every Alan Parsons Project song... the list goes on!)
Fair enough. But just taping the inlet is no cost and little effort to do or remove. Would be interesting to see how it works with the right hand to complete the chord as needed.
 
Steve, What is the brand and model of your instrument or is it custom made?

I have the "Petit Chroma" from the Bernard Loffet Workshop.


The current production model is slightly different from the photo, as they now have 36 treble buttons. (You may find photos of an earlier version that had 20 bass buttons in a different arrangement.) These can be customized to any configuration you want. This is a great lightweight, melodeon-sized CBA that works well for the type of folk music usually played on a diatonic. I like the sound of the open chords just fine. I also have a larger CBA with Stradella bass, so this is not my only accordion.
 
My point in mentioning this is that for the experienced piano accordionist who wants a small, lightweight instrument, this type of 24 bass system would be a much better choice than a greatly abbreviated 12-bass Stradella. I suspect it would have to be custom made, however. Those 12-bass models are intended to be beginner instruments only.

However, if you can remove the thirds on the 12-bass, you would add a little more versatility so you could play in several major and minor keys. It is a compromise, but if you are playing in a band, the guitar or piano player is there to do the full harmony. Many diatonic accordions come with a stop for removing the thirds, because the open chord sound is preferred by many folk accordionists.
 
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My point in mentioning this is that for the experienced piano accordionist who wants a small, lightweight instrument, this type of 24 bass system would be a much better choice than a greatly abbreviated 12-bass Stradella. I suspect it would have to be custom made, however. Those 12-bass models are intended to be beginner instruments only.

However, if you can remove the thirds on the 12-bass, you would add a little more versatility so you could play in several major and minor keys. It is a compromise, but if you are playing in a band, the guitar or piano player is there to do the full harmony. Many diatonic accordions come with a stop for removing the thirds, because the open chord sound is preferred by many folk accordionists.
I definitely agree what you describe is a much more capable system. And I definitely appreciate its utility. My ends however would be a low cost instrument I could play a bit on camping trips or on the boat without worrying too much if it succumbs to exposure to the elements or other hazards of rough use.
 
By a traditional definition chords are at least 3 parts. One could argue that open chords aren’t truly chords, but to me that’s just a question of terminology.

Open chords work by having the third (even as it’s not sounded) being implied by the rest of the musical context. So if you play an A open chord (A and E) when the melody is in the key of C the open A chord will be interpreted by the listener as being an A minor.

I don’t understand what your reply on one chord was referencing. In my proposed update to a 12 bass would have 9 of the bass buttons remain as original so the 6 in the bass row would remain as they are and the Bb, F, and C major would stay as major. Just modify the G,D and A major buttons to be minor. So you could play a wider array of songs with left hand accompanyment (after transcribing them to the key of F major or it’s relative D minor.)
Ah yes, as I said, it was my misunderstanding. In my ignorance I had assumed you were going to change to only one key eg F with the relevant major and minor chords. Obviously I hadn't thought it through. Please ignore my last reply?
 
I definitely agree what you describe is a much more capable system. And I definitely appreciate its utility. My ends however would be a low cost instrument I could play a bit on camping trips or on the boat without worrying too much if it succumbs to exposure to the elements or other hazards of rough use.
I understand your situation, get the cheap instrument and make the simple modification.

I guess I am just trying to spread the word about this somewhat revolutionary fully chromatic bass for small accordions. It is not really new, it has been around for a while, but not many accordion makers have caught on to it. It has been a revolution for me, as I have long wanted a melodeon sized accordion for folk music sessions, without having to learn to play a diatonic. (I think diatonics are cool, but that was not the choice I made long ago.) The Petit Chroma is almost half the size and weight of my medium sized 60-bass CBA. There are many advantages to a small accordion.
 
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