Double Bass Crab technique?

[Thomas Allin]

It is present (but perhaps sometimes overlooked) in Petracchis book "Simplified higher technique". Even in the lower positions as in exercise 16.

 

[Les Fret]

Thanks for those Petracchi examples! That last one shows it well. Just tried it. I just wander what the extra benefit is of the crab in this specific example as opposed to playing it normally? You don’t necessarily gain more speed. Maybe it is a little more fluent but it’s not night and day.

And do you always leave the first finger on the string when doing the crab/anticipation? Or do you lift it off when playing the fourth finger? Just to be sure.

 

[PaulCannon]

Thanks for those Petracchi examples! That last one shows it well. Just tried it. I just wander what the extra benefit is of the crab in this specific example as opposed to playing it normally? You don’t necessarily gain more speed. Maybe it is a little more fluent but it’s not night and day.

And do you always leave the first finger on the string when doing the crab/anticipation? Or do you lift it off when playing the fourth finger? Just to be sure.

You could play the whole figure (those last 5 bars) in one bow, perfectly legato. It works.

I couldn't say what Petracchi intended, but Rabbath's concept is that one finger always serves as an "anchor point" for the rest of the hand and wrist to pivot around. In this last example (last five measures), the hand contracts when the first finger is down, and expands when the fourth finger is down. This is also achieved with a rocking motion in the arm/wrist. The string is always in contact somewhere with the fingerboard.

 

[Chris Fitzgerald]

... Rabbath's concept is that one finger always serves as an "anchor point" for the rest of the hand and wrist to pivot around.

Well put. I was looking for a pithy way to put this concept, and you just posted it. I would call this the essence of crab technique, since without a stable anchor you are talking about a shift instead.

What you you learned classical gentlemen call the thing I describe to my students as a "shivot" - when the thumb rotates around its fixed point on the back of the neck to reach an extra note above with 4 or a lower note with 1? I just use shivot because it amuses me, but there's probably an official name for that that I should be reminded of!

 

[wathaet]

What you you learned classical gentlemen call the thing I describe to my students as a "shivot" - when the thumb rotates around its fixed point on the back of the neck to reach an extra note above with 4 or a lower note with 1? I just use shivot because it amuses me, but there's probably an official name for that that I should be reminded of!

Pivot

 

[Chris Fitzgerald]

Pivot

Well that's no fun!

EDIT: Come to think of it, I think I use the "shivot" term to mean pivoting the thumb to reach notes adjacent to the original position of up to a whole step in either direction of the basic 1-2-4 fingering unit.

Students with large hands can reach the extra whole step above with a simple pivot, while students with small hands have to slide the thumb a little bit to get it. Below, just about everyone has to slide the thumb to get the whole step below, but in a shivot the aim is to magnetically snap back to the original position with as little motion as possible.

 

[Les Fret]

But pivot is not the same as the crab technique. Crab technique is anticipating with the next playing finger while still holding down another finger. Pivot is rotating the thumb as an anchor at the back of the neck to be able to reach more notes with the fingers without shifting.

I use pivots fairly often but yet have to find practical use for the crab. I can see the benefits when using the left hand thumb crab technique to move around to different positions in thumb position but with the first finger it is less obvious (both in lower and thumb positions).

 

[Chris Fitzgerald]

But pivot is not the same as the crab technique. Crab technique is anticipating with next playing finger while still holding down another finger. Pivot is the rotating the thumb as an anchor at the back of the neck to be able to reach more notes with the fingers without shifting.

Yes, of course - pivot is about the thumb anchor on the back, and crab is about the finger anchor on the front. Sorry if I threw a wrench in the thread!

 

[yodedude2]

well thivot then

 

[Chris Fitzgerald]

Thirtainly, thir!