Why won't this work????

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Jake L
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Joined: 4 Aug 1998 11:00 pm
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Why won't this work????

Post by Jake L »

OK...In theory, I should be able to lower my 6th string with my RKR a full step. Then raise it 1/2 step with my B pedal, and it be in tune (kinda). However, in practical application, the B pedal winds up raising it almost to the starting note. Activated individually, the B pedal raise is in tune, as is the RKR lower. Why not when used together? Any ideas?
SteveTodd
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Post by SteveTodd »

Not sure of the exact mechanics involved here but my guitar has this change and it is perfect. BUT, my gutiar has a feature on it called a "tunable split". Following the procedure provided in the instruction manual
I can tune this change perfectly. Basically, there is an extra "raise" pull rod on that string that is used to "fine tune" the split. The point is that the builder recognized a need for a feature to accomodate this split combination. Hope this helps.

Steve Todd - Carter S-10
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Jon Light
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Post by Jon Light »

Just suffice it to say that within the leverages and radii of an all-pull changer it just isn't that simple. But if you say what kind of guitar you have and how many raises/lowers the changer can do (triple/double? Triple/triple?) there may be a simple solution to creating a tunable split.
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Jerry Hayes
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Post by Jerry Hayes »

You're don't have a push-pull do you? Image

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Livin' in the Past and the Future with a 12 string Mooney Universal tuning.

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Chuck Martin
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Post by Chuck Martin »

Jake,

Depending on the type of guitar you have a tunable split can be added. You will need to add a "raise" pull for the right knee lever that lowers string 6 then adjust as follows:

1) push down your B pedal and hold. (make sure that its in-tune and properly adjusted)
2) now engage your knee right knee lever and with a tuner adjust it so that you get an in-tune "G" (split of the 1/2 step raise on the B pedal and the whole step drop on the knee lever)
3) release the B pedal and check the right knee lever by itself with the tuner. (it should be flat)
4) with the lever engaged, tune the new raise on the lever to bring it back to the correct pitch (F#)
5) release the lever and check to make sure your open note is still correct

With this method you should be able to get an in tune "G" using the B pedal with the right knee lever. <FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Chuck Martin on 16 April 2003 at 12:26 PM.]</p></FONT><FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Chuck Martin on 16 April 2003 at 12:29 PM.]</p></FONT>
C Dixon
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Post by C Dixon »

I agree with, "it isn't a P/P is it?" Because P/P's lowers are overiden by raises; meaning they do not split as all pull guitars do by their inherent design.

P/P's CAN be made to split, but it is cumbersome and hard to setup. Most are setup to overide.

On all-pulls, "splitting" is normal. When you raise a string (for example), a half a tone and lower it a tone, the note will end up near a half tone lower. The opposite is true. If you raise a string a whole tone and you then lower that string a half a tone, you end up close to a half tone raise.

The problem on all-pulls is, the split note is usually not in tune. And some method must be used to "tune" the split note. The two most common types of tunable splits are:

1. Adding a second rod (raise) to the lower bellcrank.

2. Using the Emmons' type; where an allen set screw is threaded into the metal bar just to the right of the changer fingers on top of the guitar.

Since the extra rod tuning procedure has been covered, the following will tell how to tune the "allen split screw" method:

1. Tune the B pedal as normal.

2. Engage the B pedal and while holding it engaged, engage the knee lever that lowers the 6th stting a whole tone. Tune the lower nylon tuner for the correct G note "split".

3. Release the B pedal keeping the knee lever engaged. The half tone lower note will be way flat. Tune the allen screw to bring the string back up to the correct whole tone lower.

Note: On splits where one or more of the notes is tuned JI, this may not work. An example is where one tunes the B to C# to pure JI; and tries to split that note with the B to Bb change.

What will happen here is; if you get the split correct, the Bb note will be too sharp and I know of no way to correct this.

This problem will NOT occur if one tunes the B to C# to ET. Or close enough to it, so that the resultant B to Bb change is NOT sharp. (IE, either in tune or flat).

The reason is; all splitting methods that I know of, depend on the lower to end up flat. Then either the extra rod, OR the Allen screw is used to sharpen the note til it is in tune. Neither of the methods was designed to flatten the note if it is too sharp, which is the case when one tunes the B to C# to pure JI and the B and Bb notes are tuned ET.

carl
Jake L
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Post by Jake L »

Thanks Guys!
I have a Carter D-10. I guess I'll add this split tuning.
Jake Lowe
Dave Krute
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Post by Dave Krute »

I have a Carter D10 also I think you have a tunable split already.
rhcarden
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Post by rhcarden »

I have this change on my P/P but I don't use the B pedal. I lower the 6th G# to F# with pedal 1 and pull it back to G with my RKL. RKL also lowers strings 2 and 9. Since this ain't no "all pull guitar", it does nothing to string 6 unless pedal 1 has been pressed.



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Bob Carden 66 Emmons P/P 8/9
BMI 13 string 7/7
<FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by rhcarden on 16 April 2003 at 10:01 PM.]</p></FONT>
Dave Potter
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Post by Dave Potter »

Carl -

Thanks for your explanation of split tuning with hex type adjustments.

My new Fessy has those, and I didn't have a very good understanding of that.
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